9 ms·

Show HN: I built a synth for my daughter

1278 points by random_moonwalk 10mo ago

rmnclmnt 10mo ago
Your daughter is so lucky! I meaning the physical UX is very reminiscent of teenage engineering, looks great! The more I was scrolling down the article the more I hoped for an « order » button :)
skrebbel 10mo ago
wow
greasegum 10mo ago
This is an inspiring project! I would love to see more stuff like this and updates if you decide to evolve the project further.
- random_moonwalk 10mo ago
  Thanks so much! Please drop your email here and I'll keep you updated with any next steps: https://tally.so/r/Y55dXv https://tally.so/r/Y55dXv
lovegrenoble 10mo ago
Absolutely, Kickstarter is a good idea
eat_your_potato 10mo ago
Reminds me of the concept of the Data DUO, very inspiring
0xdada 10mo ago
Wow! Looks great and very inspiring. Great idea to make separate components that can be connected - something like a drum machine, sequencer, maybe even a chord synthesizer? It can be constrained such that you are always diatonic, you could have a mode knob too. Jamming with other people can be a life changing experience, and to do that as a child would be a great privilege to have.
- random_moonwalk 10mo ago
  Yes exactly, it would be great to be able to sync the clocks so they all ‘just work’ together. And maybe also a module that gives all the other synth parameters for the more advanced user too. I say it’s for my daughter, but I actually would love this too.
- andoando 10mo ago
  Im not sure youre aware of this but look up modular synthesizers. This is how electronic music was made starting in the 60s/70s
nimrody 10mo ago
It's beautiful and the demo video shows how someone with music background can make even such a limited tool sound so amazing.
dmd 10mo ago
Very cool. Reminds me of things like the Blipbox myTRACKS and the CHOMPI.
fiatpandas 10mo ago
Regarding case material for productizing, you could consider a combination of plywood and bent sheet metal, eg like a Moog. Also check out dato.mu for a few examples of kid proof synth enclosures.
- Thorrez 10mo ago
  Would bent sheet metal have any sharp corners or edges? For kids it's probably best to avoid those.
  - bluGill 10mo ago
    That depends on how much effort your spend on finish work. Files and sandpaper works wonders, but that take time. Or you can fold the edges over so that the sharp edges are on the inside (cars do this). The plywood is likely to cover all those sharp edges - plywood is easier to shape than sheet metal so this is a common cheat that can look good if done right.
  - fiatpandas 10mo ago
    You can debur it as part of the manufacturing process, and then when it gets powder coating it smooths out even more. But you can just embed the sheet metal edges in a groove on a wooden side.
dude250711 10mo ago
Another good option for a child: https://www.eltamusic.com/solar-42 https://www.eltamusic.com/solar-42 On a serious note: https://www.ericasynths.lv/shop/standalone-instruments-1/bullfrog https://www.ericasynths.lv/shop/standalone-instruments-1/bul...
- eitally 10mo ago
  Perhaps more realistically, Teenage Engineering products: https://teenage.engineering/store https://teenage.engineering/store
  - persedes 10mo ago
    yes, the pocket operator is a great gift for 8-9+ year olds if you're not as talented as OP :D
- nrhrjrjrjtntbt 10mo ago
  Why is the first link not serious?
tanepiper 10mo ago
I'm a 44 year old man and I would love this - for years I've tried to dabble with music with much lack of success - but this looks really fun to play with. Great job.
- bluGill 10mo ago
  The problem with music is you can't dabble. You need to dedicate half an hour per day for a few weeks before you reach the point where you are not terrible. You need years of dedicated practice before you can call yourself good. Finding that time is hard. Still making your own music is run and so I encourage you to press through.
  - exitb 10mo ago
    Not trying to get good is a liberating step. I never was and never will be good at music, but it’s still fun to play loud punk-ish tunes on a guitar, or twiddle the knobs on a faux-303, none of which requires years of your life.
- 0xMalotru 10mo ago
  Go grab a Teenage Engineering Pocket Operator, it's definitely worth a try ! I personally recommend the PO-33 (KO!), it is fun and easy to play with :)
  - semi-extrinsic 10mo ago
    The POs are fun to play with, but from experience I would much rather recommend getting a used mk1 Novation Circuit. For $150 - $200 you have a four track drum machine plus two tracks of a great synth engine, with a built in mixer and simple effects, midi in if you want to use a keyboard, and the thing is still compact and battery powered.
- fainpul 10mo ago
  There are also free software synths and DAWs available. GarageBand is the obvious one if you use macOS. I had lots of fun with that and with NanoStudio on iPad. I also own a Pocket Operator, which is fun and very mobile, but a bit pricey.
BjornW 10mo ago
What an awesome project. It looks fabulous! Reminds me of the Dato Duo I have. The "Dato Duo" is also a synth aimed at kids. It allows 2 kids to play together. it is made by a Dutch company called Dato (https://dato.mu https://dato.mu). Their latest musical invention the "Dato Drum" had a successful Kickstarter and is shipping now. This drum machine allows even more kids to play together. PS: As the owner of a Dato Duo I can share you a little secret: it's also fun for adults :)
- perelin 10mo ago
  Love my Datos (also own the drum now)! My kids are jamming with them regularly. Only issue: my youngest LOVES the "Crush" button and just holds it the whole time. Not easy for noise sensitive parents :)
Waterluvian 10mo ago
If I have zero experience designing PCBs but wanted to do a similarly (non)-complex one, how much of a tall order would that be? In my completely made-up mental model, I'm guessing I just take the parts I've already breadboarded, look them up in some sidebar, and drag and drop them around, snapping to nice clean spacing, and then connect all the various pins together and have it automatically organize things? We're not going for perfect here. Just "Baby's first PCB" that at least works. And then when I have one designed, how much would it cost to get made and sent to me if I was okay if it took a month? But most importantly: how do I build personal confidence that I'm not shipping a potato off to be printed? Is there a community I could ask for a review from?
- jmb99 10mo ago
  If the board is small (10x10cm or less) it will be almost completely free, like single-digit dollars, through somewhere like JLPCB. So I’d say don’t worry too much about that, just jump in and try! As for actually designing, it’s a little more complicated than that but not by much. I did my first pcbs with KiCAD ~5 years ago by pretty much just guessing and googling where things were. Completely feasible if you have 0 background experience.
- random_moonwalk 10mo ago
  Hi, your mental model is essentially correct, though it took me a good few evenings over a couple of weeks to get the workflow down in fusion 360. The electronics retailer will usually have the footprint and 3d model available on the component page. You can then import it, define which pins you want connected to each other in the footprint and in the PCB editor you can drag the routes (wires) to connect them. Printing is way cheaper than I initially thought it would be - I paid £35 or so, including delivery and 5 of them arrived in 5 days. You can get cheaper delivery though. Also most of that cost is shipping and the setup fee - the marginal cost for each additional PCB print in the order is on the order of low single digit dollars. Tbh my circuit was fairly simple so I just took a bit of a chance (and some extra care wiring things up). I think there’s a subreddit where people give feedback though I haven’t submitted anything.
- bluGill 10mo ago
solfox 10mo ago
Looks amazing! Reminds me of a funny reddit thread about a man who built a fiber optic star ceiling for his daughter. The top comment was "First child?". :) https://www.reddit.com/r/DIY/comments/8g8pce/fiberoptic_star_ceiling_in_my_daughters_nursery/ https://www.reddit.com/r/DIY/comments/8g8pce/fiberoptic_star...
- Brajeshwar 10mo ago
  And then the things you do to redeem your guilt for the second child is a whole interesting area.
  - random_moonwalk 10mo ago
    That's what the drum machine module is for.
  - sroussey 10mo ago
    And then they give up by the fourth. Guess which one I was, lol.
  - Bengalilol 10mo ago
    Hi Brajeshwar (back to the old flashcoders days). Children grow up and in the end you get the full orchestra ^^
    - Brajeshwar 10mo ago
      Those were the days. It was blunt, wild, and erratic but we had fun.
  - solfox 10mo ago
    When I first saw the starfield post, I had one kid. I was building her all sorts of cool stuff: brio table, custom childrens book, etc. So naturally, I disbelieved the assertion that my second child would get anything less than my first. Alas, the insight is spot on - for all your good intentions, the second child gets shafted. I think it's just one of those things you have to experience to get it.
fny 10mo ago
Great work! This brings back memories of futzing with knobs on a boombox as a kid. For your sake, I hope you built a heaphone jack.
- random_moonwalk 10mo ago
  Thank you! Unfortunately I decided to save that feature for v2!
  - gus_massa 10mo ago
    Strong sugestión for v2: Add a hidden knob to regulate the max volume. Kids love to raise it to the max. (In a tablet, I had to secretly add some transparent tape between the speaker and the plastic cover case.)
gulan28 10mo ago
This is awesome. I had vibecoded something similar called https://chippytune.com https://chippytune.com for myself. Still working on wav support though
habosa 10mo ago
This is fantastic, as a hardware synth lover and a dad you’re making me pretty jealous.
ronbenton 10mo ago
Wow looks professional
fainpul 10mo ago
> A 3D-printed enclosure is fine for a prototype, but a real product likely needs injection-molded parts, which require expensive tooling. For kid-friendly toys, yes. But for older users not necessarily: https://teenage.engineering/products/po https://teenage.engineering/products/po
- speedgoose 10mo ago
  I have two of those. They are great additions to my drawers. One has a silicon case and is nicer to use though.
  - NoSalt 10mo ago
    You say "they are great additions to my drawers". Is that because they suck, or is it that you don't have the time to enjoy them? (which I totally understand) I have seen these before and didn't know if they were worth the money. What is your opinion on them?
    - brudgers 10mo ago
      On one hand, $100 will buy a lot of hamburger. On the other hand, it's relatively low for a musical instrument and pretty easy to justify when if you suffer from gas. I am only speaking for myself, but I have a drawer of small musical electronics that I use occasionally. I bought them because I was curious.. I keep them because they are musical and not worth selling.
    - speedgoose 10mo ago
      I have the PO-12 (drum machine), and the PO-33 (sampler). They are somewhat limited but that can a good creativity booster. I don’t use them often because I’m not a great musician. I think they were worth the money, for sure.
- elric 10mo ago
  Wood is also pretty child friendly. But neither injection molding nor carpentry will protect a synth from a child dunking it in a puddle of water.
gwbas1c 10mo ago
Makes me wonder what the difference, in definition, is between a sequencer and a synthesizer? Is this really a synthesizer, or is it really a sequencer? Yes, I'm splitting hairs about semantics.
- butlike 10mo ago
  A sequencer is always in steps. A synthesizer has a signal generator and can modulate a single step. This toy is both a synthesizer and a sequencer, but since you cannot toggle the 4 steps off, it will always be a sequencer in addition to the synthesizer
- PaulDavisThe1st 10mo ago
  The answer to your question is "yes". It is a synthesiser AND it is a step sequencer.
- dave_sid 10mo ago
  Both
- oidar 10mo ago
  The linked project is both. A synth makes sounds, and a sequencer controls the sound over time usually with note on/off data. This sequencer has 4 steps before looping back to the beginning. To simplify, think of a sequencer as the music box drum and the synth as the tines in a music box.
- strogonoff 10mo ago
  A synthesizer is generally a higher-level ready-to-use product containing any number of oscillators, sequencers, and other circuits and bells and whistles under the hood. A device with an oscillator and a sequencer qualifies as a basic synth. At a lower levels you find modules like sequencer, oscillator, etc. They are generally not used by themselves: you plug a sequencer into an oscillator to make use of it, just like a standalone oscillator by itself simply makes a continuous noise that gets old quickly. A synth does that connection for you and exposes the controls. (To make things even more fun, the lines between lower-level audio modules are often blurred. For example, the difference between a sequencer and an oscillator can be best summed up as: the former is commonly designed for unipolar control rate signal change where you can specify exact level per step, while the latter is designed for bipolar audio rate signal change between two predetermined extremes—however, as the “designed for” hints, you could configure some sequencers to output a bipolar signal changing so fast it is audible, just like you could run a square wave oscillator so slowly that it becomes a 2-step sequencer.)
phplovesong 10mo ago
As a father to a daughter this warms my heart. Well done daddy! Points to you!
NickC25 10mo ago
that's great! may your daughter make great use of it! love the fact that your step sequencer even has a display to tell you what note you are adjusting to and from. i've always found that tuning synths and sequencers both analog and digital can be a pain because you can forget the note (or you don't have a good set of ears or perfect pitch) even if the result sounds good.
binary132 10mo ago
Totally rad! Makes me think about what kind of simple programming could be possible with a minimal HCI like this.
tapland 10mo ago
This is great. I’m going to start making something like this, but with some cut apple wood knobs, for my birds.
bitwize 10mo ago
The other day I came across a post on Facebook that was just some guy grousing that the new Teenage Engineering gadget looked like "a baby's activity center". And now we've come full circle: a baby's activity center that's actually not far off from Teenage Engineering kit.
afandian 10mo ago
Amazing the things we do for our little ones. I built a toddler-friendly keyboard for my son. He's still playing some form of piano 6 years later, no longer with his fists or feet. https://blog.afandian.com/2019/09/ux-for-toddlers/ https://blog.afandian.com/2019/09/ux-for-toddlers/
- newtwilly 10mo ago
  Beautifully done!
- beAbU 10mo ago
  Thank you for that closing paragraph in your article. Every time I read something online that tries to bend it into some "profound" lesson, or integrate it into the writer's personal brand, I throw up a little. This is most egregious on LinkedIn, and why I avoid that place unless I have to find a new job or something.
danvoell 10mo ago
This is awesome. Just awesome. Love that it looks like a baby toy and packs enough punch to get a kid about 20 years up the line of music understanding.
cjonas 10mo ago
I've been learning CAD, 3d printing, PCB design and brushing up on my embedded programming... all with the goal of being able to build toys for/with my son. It's incredible how accessible it is in todays world, made possible by these advancements: - incredibly powerful and cheap microprocessors (esp-32) - Fast, high precision desktop 3d printers - Affordable small batch PCB manufacturing - LLM's to advise on circuit design and help with embedded programming Would you have any interest selling a non-comm license to the PCB, f3d files and source code? My 1.5yo son would absolutely love this!
- mcrider 10mo ago
  Same, I recently got into Arduino so i could build a toy idea I had for my kid (a sort of "keepy-uppy" paddle game). I've always avoided Arduino projects because I don't like to code in my spare time (its my day job) and also learning how to wire things seemed daunting -- LLMs solved both of those problems for me (Claude's wiring tutorials are awesome and the code is simple enough that it can one-shot it). I also bought a Bambu A1 3D Printer and it is unexpectedly way more fun and useful than I thought it would be. I designed the toy in TinkerCAD and it printed out beautifully (I also have been printing out lots of other toys and yes, useful things for around the house and for other projects). Next steps are learning Fusion 360 and figuring out PCBs -- That also seemed daunting to me but its nice to see other amateur hobbyists are seemingly picking it up with not much difficulty.
  - cjonas 10mo ago
    I highly recommend the "learn fusion 360 in 20 days" series on YouTube. I think I did it pretty causally in half that time. Then just find excuses to design stuff. After about a year of random projects, I can pretty proficiency draw most simple assemblies. This morning my son broke the battery hatch on his favorite toy and within an hour I had a replacement printed. (ducktape would have certainly been faster but where's the fun in that ;) One thing I would point out is if your interested in organic shapes that blender is the better tool to learn/use. Fusions surface modeling is pretty hard to work with.
JoeDaDude 10mo ago
Cool! Reminds of the Music From Outer Space synth in which the designer makes the claim that it "can actually get a child away from a television" and includes a video to prove it. https://www.youtube.com/watch?v=i6M_KrZByz4 https://www.youtube.com/watch?v=i6M_KrZByz4 MFOS Weird Sound Generator https://musicfromouterspace.com/index.php?CATPARTNO=WSG001&PROJARG=WSG2010%2Fwsg_page1.html&MAINTAB=SYNTHDIY&SONGID=NONE&VPW=2137&VPH=1063 https://musicfromouterspace.com/index.php?CATPARTNO=WSG001&P...
thenthenthen 10mo ago
Looks so nice! The sam is a midi synth chip right? Super cool. How/where did you get the knobs?
- random_moonwalk 10mo ago
  Thanks! Yes it's a little digital synth that receives MIDI. I used Chroma Cap knobs: https://store.djtechtools.com/products/chroma-caps-knobs-and-faders https://store.djtechtools.com/products/chroma-caps-knobs-and...
  - thenthenthen 10mo ago
    Aah kool, i had one in a arduino format board, was great to cycle through all the instruments randomly + some sequence/chords. Instant Aphex Twin
oldestofsports 10mo ago
This is very impressive, it looks great!
BigTTYGothGF 10mo ago
The traditional approach is you give noisemaking toys to your niblings, not your own children.
- random_moonwalk 10mo ago
  This sounds like a lesson I’m going to be learning the hard way
  - brudgers 10mo ago
    Good parenting is doing things the hard way. So why not go all in with a full set of acoustic drums?
    - bluGill 10mo ago
      Do you have $800? I'm trying to get my daughter a full set of acoustic drums (though odds are her brother will use them more even though he plays clarinet and she does percussion). I've seen full sets for as little as $30 - but it doesn't take much checking to realize they are not worth it even at that price. Good sets quickly cost more, but $800 is a good starting point for a set that isn't unusable.
      - brudgers 10mo ago
        Keeping in mind that you can’t buy a new Stradivarius… Maybe try Facebook Marketplace, Craigslist, etc. because drum sets take up space quality drum sets and other large instruments are often priced where moving the gear is part of the payment.
- beAbU 10mo ago
  We've been following this. Every nibling or even the offspring of friends received xylophones, tin whistles, hand drums etc. As long as it's not battery powered, it was on our "approved" list. They love us (the kids. The parents... not so much I guess). We have our first one due in a couple of weeks, and I guess we'll prepare ourselves for retribution!
warrenmiller 10mo ago
is it feasible to built one with a PCB? just straight to the UNO like your initial prototype - did that work ok?
NoSalt 10mo ago
This is absolutely FANTASTIC, and I am humbled by your mad skillz! My son and I are also fascinated by the sweet, sweet synth sound, but as I have no discernible talent, we went this route: https://www.sweetwater.com/store/detail/Nts1Mk2--korg-nutekt-nts-1-mkii-diy-digital-synthesizer-kit https://www.sweetwater.com/store/detail/Nts1Mk2--korg-nutekt... Which, unfortunately, has a HUGE learning curve in terms of operation.
rcarmo 10mo ago
This is great. I did a similar thing when my kids were young (revived an old, dead Kawai synth with a Raspberry Pi and sound fonts), but doing it with semi-discrete circuits seems a lot more fun.
broast 10mo ago
So cool, I think all kids would love this
bbhi 10mo ago
Looks like a fun project. I can highly recommend Teensy Audio Library for audio projects: https://www.pjrc.com/teensy/td_libs_Audio.html https://www.pjrc.com/teensy/td_libs_Audio.html
- gregsadetsky 10mo ago
  Mozzi (for Arduino) is also great! https://sensorium.github.io/Mozzi/ https://sensorium.github.io/Mozzi/
simgt 10mo ago
As someone who has never 3d printed anything, I'm surprised by how clean the case looks as opposed to what we usually see. Why is it so smooth?
- TheSilva 10mo ago
  Sanding and polishing, likely.
  - bvm 10mo ago
    Nah, it just came out like that (i printed it :D) We experimented with ironing, but you can't see it in those views. The A1 is a pretty good printer OOTB. There were a few iterations on the case design though to optimise the edges.
- gpm 10mo ago
  The surfaces you're seeing in the pictures are almost all the "bottom" surface that was printed directly on the build plate. It basically just picks up the texture of the build plate and is otherwise smooth. That's actually a fairly bumpy build plate they printed it on (which lots of people like for aesthetic reasons). That said modern 3D printers are good at producing pretty nice parts these days, especially if you print with small layer heights. You might be underestimating the possible quality of 3d printed objects.
sgallant 10mo ago
My kids would love this.
woolion 10mo ago
Were you aware of the Dato Duo (https://dato.mu/ https://dato.mu/)? It's very cool for kids, except for the fairly steep price point. The advantage is that it's limited, so it greatly reduces the wall of difficulty to manage to get some 'nice-sounding' music (mostly the restriction to the pentatonic scale). However, kids still manage to find the most horrible-sounding settings, and insist on keeping them as is...
helsontaveras18 10mo ago
Wow, what an amazing demo for such a simple synth. Great work! If you ever start a Kickstarter, I’d be happy to donate. If it inspires some kid out there to get into music production, it’s a win for me :)
giancarlostoro 10mo ago
Would love something like this for my daughter, but with a max volume option she can't tamper with LOL
- bigiain 10mo ago
  That's a great reason to redesign it around an ESP32. So you can have an app on your phone that lets you control the volume over WiFi...
RobertWesner 10mo ago
I can't put into words how awesome this is. Perfect demo.
PaulHoule 10mo ago
Kinda funny but my adult son has taken an interest in guitars and keyboard and that has me working on MIDI routers with AVR-8 and building an ESP32 based synth module.
yzydserd 10mo ago
I was too fascinated by the different thumb nail lengths to concentrate much on the video.
- random_moonwalk 10mo ago
  I trained as a classical guitarist, so I maintain some longer nails on my right hand :)
rock_artist 10mo ago
What I love about this is how physical it is. So yeah, there's some board running DSP. but the design is amazing. It really relates to some recent posts also in HN about many objects loosing their physical UX. from an age of having buttons and tactical interfaces, everything became more touch based / app based which indeed cut price and allows easier updating. but also lacks some romance which is exactly what this device shows.
- brudgers 10mo ago
  Reminded me of a BlipBlox… https://blipblox.com https://blipblox.com
  - bigiain 10mo ago
    Reminded me of Teenage Engineering's Pocket Operators: https://teenage.engineering/store/pocket-operators https://teenage.engineering/store/pocket-operators I have a few of those, and heaps of my friends gat sucked deeply into playing with them at the expense of whatever they actually came over for. "Nah, I'm not hungry. You should all eat without me, I'll just finish tweaking this groove." They're aimed (as the company name hints) as a little older than 3 year olds. One hint for the OP, it's so cool how you can plug those toys into each other in a chain, and have them all sync - so the percussion, base, and melody can all be programmed on threee different POs, and automatically play together.
    - yumraj 10mo ago
      What would you say is the best one to start with, say for a young middle schooler? Maybe best 3, in order?
      - bigiain 10mo ago
        I don't think it matters all that much. Any specific opinions are going to be more a natter of personal taste. Get one aimed at rhythm/percussion, one that has some bass/lowend sounds, and something to make melodies. I have a PO12, PO14, and PO16. If I was going to buy another one it'd be a toss up between the PO33 and the PO35. If I were starting from scratch I think I'd still get the PO14, I might get a PO24 or PO32 instead of the PO12, and I might get a PO28 instead of the 16. Or if said young middle schooler has access to sounds they can sample easily enough (like, say, Garageband on an iPad_ maybe jump straight to one of the sampling ones (PO33 or 35) for the lead/melody sounds.
mttch 10mo ago
This is great, i’d kickstart it, my 5 year old would love it.
Krisso 10mo ago
Dad of the year <3
tmilard 10mo ago
I'm not a kid. I still want it !
- pragma_x 10mo ago
  Same. It's a solid four-note ARP that sticks to a fixed set of musical keys. You literally can't make bad sounding music with this. A more grown-up version of this would be 16 notes, with variable length patterns (4-16?), and a "swing" function. A little bit of I/O mux under the hood and I bet this design could be expanded in that way. Or maybe you just daisy-chain multiple sequencers?
  - brudgers 10mo ago
    This ends at Eurorack.
    - pragma_x 10mo ago
      It _all_ ends at eurorack. Especially my bank account.
chaosprint 10mo ago
Great finish. I was busy designing and soldering the prototype synthesizer during the summer, but I had to put it on hold because my baby was born in September. I had the same problem back then: injection molding is quite expensive to start. But you could consider a more creative approach: using a PCB directly as the panel, such as a TE's Pocket Operator. Korg also has this solution for some educational products. Alternatively, you could use 3D printing; there are many inexpensive services in China. CNC doesn't have the mold-making issue, but it's more expensive and doesn't seem suitable for children. Another interesting point: after my child was born, I didn't have much time for my sound work. But recently, I was surprised to find that I spend most of my time playing white noise on Glicol (http://glicol.org/ http://glicol.org/) and it works great for my kid. ``` o: noise 42 >> lpf ~mod 1 >> mul ~mod3 ~mod: sin ~mod2 >> mul 200 >> add 1000 ~mod2: sin 0.1 >> mul 0.04 >> add 0.1 ~mod3: sin 0.04 >> mul 0.3 >> add 0.8 ``` Good luck with kickstarter!
Joeboy 10mo ago
It's not kid friendly, but in case anybody's interested I just wrote up how I made a simple "hardware" synth by bodging together a Raspberry Pi Pico 2 and I2S audio module, total cost around £10 on Amazon UK. The hardware's very cheap and easy. The "default" synthesis is pretty simple but also pretty hackable (in Rust) if you want to customize it. https://github.com/Joeboy/oxynth/ https://github.com/Joeboy/oxynth/
- afandian 10mo ago
  Thanks for sharing! I did some similar playing around with an ESP32 and I2S a few years ago (lockdowns were an odd time). Where I seem to remember getting stuck was how to get the phase to line up, so that each sample looped at a zero-crossing point (which is different for each frequency). For the lazy, what did you do? https://gitlab.com/afandian/melodicornamuse/-/blob/main/melodicornamuse.ino https://gitlab.com/afandian/melodicornamuse/-/blob/main/melo...
  - Joeboy 10mo ago
    I don't really understand your issue sorry, but my thing basically just writes the audio output to a buffer, and the DMA and PIO "automatically" send that to the I2S output. There's also some messing about with ping ponging between two DMA buffers to avoid gaps between each buffer write audio. I guess things might be quite different on the ESP32. Edit: Ok I glanced at your code, if I read it right it seems like you're writing sin waves into buffers at "init" time then copying the appropriate buffer at "run" time. Which is not what I'd do, but then I'm used to more luxurious devices. Maybe try using a fast sin approximation rather than the precomputed buffer table? https://bmtechjournal.wordpress.com/2020/05/27/super-fast-quadratic-sinusoid-approximation/ https://bmtechjournal.wordpress.com/2020/05/27/super-fast-qu... might be helpful there.
    - afandian 10mo ago
      Thanks! This was just some playing round years ago, so I don't remember much about it. I don't remember if calculating sin() at runtime was too slow, or I wanted to avoid polyphonic O(n) inside the buffer loop, or what. I bet it uses a LUT anyway. I much prefer your method of just rotating the phase!
dep_b 10mo ago
The korg monotribe is magic for kids
random_moonwalk 10mo ago
Thanks for all the kind words and feedback. There are some comments expressing interest in supporting a Kickstarter etc. If you're interested in receiving updates you can leave your email here: https://tally.so/r/Y55dXv https://tally.so/r/Y55dXv Thanks again - this was a bit of a surprise!
- nixass 10mo ago
  Seems like interest for your synth brought down Cloudflare! /s
- markatkinson 10mo ago
  Boet you broke the internet! I can't subscribe to updates :(
  - random_moonwalk 10mo ago
    Ah the Cloudflare outage has hit my form!
  - deleted 10mo ago
    [deleted]
- jbl0ndie 10mo ago
  Lovely project and a really great idea. Have you come across soft tooling for injection moulding? It's a lower cost, short run approach using much less durable moulds from various materials.
  - random_moonwalk 10mo ago
    Thank you! I didn't know that was a thing - I'm going to look into it.
  - jacquesm 10mo ago
    Before you have that working you'll have 3D printed a containerload of these ;) Besides the lack of flexibility if you want to make changes. I've used soft tooling for some projects but I was (1) never really happy with the results and (2) ended up breaking the molds quite often resulting in a lot of wasted material and expense. 3D printing is the way to go for projects such as these.
dinobones 10mo ago
This is such a good idea! Kids music toys are often just purely toys tap a button, make a sound... But the skill ceiling could be so much higher, offering the ability to learn and express themselves more. Awesome work.
- amenghra 10mo ago
  One of my favorite kids music toy is a mini piano where you have to replay one among 5-6 melodies (each melody is 5-10 notes that you have to memorize by ear — no lights involved) to unlock a little happy sound. This toy managed to keep both, dad and kid busy for a while.
- moron4hire 10mo ago
  For anyone who likes the idea of better music "toys" for their kids (i.e. not toys at all, but still easy to use) but doesn't have the capacity to build stuff like this, my kids and I love the Korg Koassilator: https://www.korg.com/us/products/dj/kaossilator2/ https://www.korg.com/us/products/dj/kaossilator2/ You can usually get them on eBay for USD$60 - 70. You do need to bring your own speakers, but a pair of cheap PC speakers are good enough, and it's a good start on creating a whole synth + effects chain. Speaking of which, there is also the Mini Kaos Pad, which is a dynamic effects processor: https://www.korg.com/us/products/dj/mini_kaoss_pad2/ https://www.korg.com/us/products/dj/mini_kaoss_pad2/ This one is a little more difficult to figure out for the kids as it is a "modifier" in the chain and they haven't quite wrapped their head around that concept yet. But still, it works great, has lots of features, and is really inexpensive for such a thing. And finally, they have a number of these mini-synths that are in the USD$30 - 50 range that are a ton of fun: https://www.korg.com/us/products/dj/monotron_duo/ https://www.korg.com/us/products/dj/monotron_duo/
TurkishPoptart 10mo ago
Good lord, you must have an amazing wife/support system to give you some peace while you designed this amazing toy.
- random_moonwalk 10mo ago
  I am very lucky in this regard, my partner is amazing indeed! Most of the work was at night, so I hopefully didn't disrupt her too much.
fabioq 10mo ago
What an incredible idea, I with every nursery to school had some of these!
ty_2k 10mo ago
Really cool project, super polished. The panda animation!
yigalirani 10mo ago
build it at scale and make a fortune
jeremydavid 10mo ago
Wow! Very cool. How hard would it be to create a "custom" sound, where you use the sliders to adjust the Attack Decay Sustain and Release?
evmaki 10mo ago
What a beautiful and charming project. Kudos for taking it all the way from zero to one with such a polished design. That's no small feat. I've built prototypes for eurorack and even with some simplifying constraints it's a lot of work. Best of luck with your Kickstarter!
amatecha 10mo ago
Ahh, this made me think of "Dato DUO", similar concept (though the Dato stuff is a little more complex): https://dato.mu/ https://dato.mu/
Bengalilol 10mo ago
I love the atmosphere, the object and the purpose.
mft_ 10mo ago
Hmm, very cool project and maybe just the inspiration I need. I bought a Baby Einstein Magic Touch Guitar for a friend’s daughter a couple of years ago, and while it was okay as a toy, it was disappointing as a musical instrument because the chords it plays are badly chosen. It’s basically impossible to play along with most songs. I’ve had the back burnered idea to buy another and improve it; maybe I will now, following a variation on your approach.
thomasqbrady 10mo ago
This is phenomenal, but my biggest question is (which is probably a more of a long-term one that comes from genuine curiosity/fascination, not doubt): does she use it/enjoy it? I'm so curious to see what happens over time. Does she learn the functions of these buttons, years before having words for what they're doing? Does she write some music? Does she grow up expecting things with knobs to be this interactive/creative? SO cool!
- blauditore 10mo ago
  3-year-olds actually have quite a vocabulary, so they can certainly talk about what the knobs are doing, maybe just not as accurately as adults. Regarding discovering functionality: The author mentions Montessori stuff, and the philosophy there is unguided discovery, "let them figure out by themselves". Not sure if that's how the author is planning to use this too, though.
nielsbot 10mo ago
Reminds me of the work of Love Hultén: https://www.lovehulten.com https://www.lovehulten.com He builds beautiful, colorful, retro-futuristic audio-visual art pieces Many are synths.
dimatura 10mo ago
There's a fun podcast by Arman Bohn/Distropolis (who himself has made some cool small-batch hardware synths) where he interviews makers of small hardware synths, https://open.spotify.com/show/30USGHPeGQ9ZyWQDyRnfcv https://open.spotify.com/show/30USGHPeGQ9ZyWQDyRnfcv might be of interest.
endorphine 10mo ago
Where would you suggest someone starts for building something like this. What kind of hardware would you suggest (preferably something with Rust!bindings). Is the one used in the original post a good starting point? I've minimal to no experience with embedded.
sunray2 10mo ago
Putting aside the beauty of both the synth and its purpose, what I'm curious about is the learning process in making this. The running theme is that you picked up several new skills 'from cold'. That in itself is impressive enough. How did you approach learning: - the necessary basic electronics; - PCB design; - 3D CAD; - your particular iterative process, among other things? I get the impression you built things incrementally, observed what happens and learnt via that feedback loop? Maybe others could share their own feedback loops, too.
- random_moonwalk 10mo ago
  I've been reflecting on this a bit. I found it very useful to have a well-defined project and focus the learning time on things that are necessary for completing it. Having a background in coding was useful because I find you end up developing a knack for isolating parts of systems and figuring out how to work on small parts that end up fitting together. I therefore focused initially on simply getting readings from a single potentiometer; if I could do that then I felt pretty confident I could read from four of them. If I could generate a midi message I was pretty confident I could send it to something that could read it etc. When I started on the PCB design I had a simple circuit already so it was a case of translating that onto a board. I didn't get too deep into any of the various parts but I found that it gave me a birds-eye view of the whole process and I now feel confident in isolating parts of them and 'zooming in' to them and refining them, building on the foundation I've developed.
evereverever 10mo ago
Amazing! Kids need more synths! My kids play the blip blop and the critter & guitari synth.
michaelhoney 10mo ago
So impressed by this, from someone with no prior experience. A1 hacker news experience, congrats
Geste 10mo ago
Oof, nice one ! I was looking for some synths for my less-than-two-years kid, after seeing their face light up when I fiddle with my Lofi 12 XT in front of them. I had all these criterias : -Something without any screens -Something simple enough -Something that could withstand some rough play I looked and looked, was considering proper Aira Compact synths, but ended up with the antiquity of the Bliptronic 5000 from Thinkgeek. https://youtu.be/6rCfhF-fNb4 https://youtu.be/6rCfhF-fNb4 They love it, the buttons are beyond fun to them, but the knobs are quite hard to turn for a little kid (1st world problem, I know) I felt they were too young for a Blipbox, and I also bought an Orba 2, we'll see how that one goes. But I dreamed of such a device, with easy to turn knobs, and colorful display, something simple to modulate sounds and just hear melodies. Seeing how you created it is both inspiring and discouraging, as someone with limited free time and electrical knowledge, but, you never know !
freshnode 10mo ago
Well done. This is really inspiring.
_adamb 10mo ago
As a EE nerd, I love this project. As a parent, it's the sort of toy I want to smash as the repetition drives me insane. What should I make that captures the awesomeness of this project without the insanity? Hmm...
doppelgunner 10mo ago
[dead]
findthebug 10mo ago
love this!
beAbU 10mo ago
I want to commend you for making this actually musical. Too often these basic synths aimed at kids are little more than a noise maker unless you really know what you are doing. My spouse and I are into music and we are pretty serious choristers. We have our first little one on the way this December, and we definitely want to expose them to making music from a very young age. Your synth looks like an excellent way to do that, as it does not seem possible to get it in a state where it's just making horrible noises, every state will be some new pleasant little jingle. Bravo!
johntash 10mo ago
My mind jumped to synths from the Fallout games, so I was disappointed to find something else, but it's still pretty cool!
dazamarquez 10mo ago
Is the plastic and other materials you used safe for children?
Dowwie 10mo ago
We have similar interests! I've been working on a DIY animatronic project that is mostly vibe-coded using Sonnet 4.5. It's my first electronics project. So far, I got the Ultrasonic Sensor to trigger led when object is less than 2 feet away. I set up a sound player and the components fried when I started the device. I have to redo all of the wiring for the sound setup again. I only have one of three sound modules that isn't bricked. The comments in this thread reveal a community of parents who are aspiring builders of high tech devices for their children. I think this community need a discord.
jacquesm 10mo ago
There's a lot of talent on display here. For someone who has never done any of this I'm so impressed with the degree of finish and care as well as the functionality of the device. It even sounds pleasant. Dad of the year award!
Rioverde 10mo ago
Just Amazing !
rickygman 10mo ago
[dead]

1278 points by random_moonwalk 10mo ago

Your daughter is so lucky! I meaning the physical UX is very reminiscent of teenage engineering, looks great! The more I was scrolling down the article the more I hoped for an « order » button :)

skrebbel 10mo ago

wow

greasegum 10mo ago

This is an inspiring project! I would love to see more stuff like this and updates if you decide to evolve the project further.

random_moonwalk 10mo ago
Thanks so much! Please drop your email here and I'll keep you updated with any next steps: https://tally.so/r/Y55dXv https://tally.so/r/Y55dXv

lovegrenoble 10mo ago

Absolutely, Kickstarter is a good idea

eat_your_potato 10mo ago

Reminds me of the concept of the Data DUO, very inspiring

0xdada 10mo ago

Wow! Looks great and very inspiring. Great idea to make separate components that can be connected - something like a drum machine, sequencer, maybe even a chord synthesizer? It can be constrained such that you are always diatonic, you could have a mode knob too. Jamming with other people can be a life changing experience, and to do that as a child would be a great privilege to have.

random_moonwalk 10mo ago
Yes exactly, it would be great to be able to sync the clocks so they all ‘just work’ together. And maybe also a module that gives all the other synth parameters for the more advanced user too. I say it’s for my daughter, but I actually would love this too.
andoando 10mo ago
Im not sure youre aware of this but look up modular synthesizers. This is how electronic music was made starting in the 60s/70s

nimrody 10mo ago

It's beautiful and the demo video shows how someone with music background can make even such a limited tool sound so amazing.

dmd 10mo ago

Very cool. Reminds me of things like the Blipbox myTRACKS and the CHOMPI.

fiatpandas 10mo ago

Regarding case material for productizing, you could consider a combination of plywood and bent sheet metal, eg like a Moog. Also check out dato.mu for a few examples of kid proof synth enclosures.

Thorrez 10mo ago
Would bent sheet metal have any sharp corners or edges? For kids it's probably best to avoid those.
- bluGill 10mo ago
  That depends on how much effort your spend on finish work. Files and sandpaper works wonders, but that take time. Or you can fold the edges over so that the sharp edges are on the inside (cars do this). The plywood is likely to cover all those sharp edges - plywood is easier to shape than sheet metal so this is a common cheat that can look good if done right.
- fiatpandas 10mo ago
  You can debur it as part of the manufacturing process, and then when it gets powder coating it smooths out even more. But you can just embed the sheet metal edges in a groove on a wooden side.

dude250711 10mo ago

Another good option for a child: https://www.eltamusic.com/solar-42 https://www.eltamusic.com/solar-42 On a serious note: https://www.ericasynths.lv/shop/standalone-instruments-1/bullfrog https://www.ericasynths.lv/shop/standalone-instruments-1/bul...

eitally 10mo ago
Perhaps more realistically, Teenage Engineering products: https://teenage.engineering/store https://teenage.engineering/store
- persedes 10mo ago
  yes, the pocket operator is a great gift for 8-9+ year olds if you're not as talented as OP :D
nrhrjrjrjtntbt 10mo ago
Why is the first link not serious?

tanepiper 10mo ago

I'm a 44 year old man and I would love this - for years I've tried to dabble with music with much lack of success - but this looks really fun to play with. Great job.

bluGill 10mo ago
The problem with music is you can't dabble. You need to dedicate half an hour per day for a few weeks before you reach the point where you are not terrible. You need years of dedicated practice before you can call yourself good. Finding that time is hard. Still making your own music is run and so I encourage you to press through.
- exitb 10mo ago
  Not trying to get good is a liberating step. I never was and never will be good at music, but it’s still fun to play loud punk-ish tunes on a guitar, or twiddle the knobs on a faux-303, none of which requires years of your life.
0xMalotru 10mo ago
Go grab a Teenage Engineering Pocket Operator, it's definitely worth a try ! I personally recommend the PO-33 (KO!), it is fun and easy to play with :)
- semi-extrinsic 10mo ago
  The POs are fun to play with, but from experience I would much rather recommend getting a used mk1 Novation Circuit. For $150 - $200 you have a four track drum machine plus two tracks of a great synth engine, with a built in mixer and simple effects, midi in if you want to use a keyboard, and the thing is still compact and battery powered.
fainpul 10mo ago
There are also free software synths and DAWs available. GarageBand is the obvious one if you use macOS. I had lots of fun with that and with NanoStudio on iPad. I also own a Pocket Operator, which is fun and very mobile, but a bit pricey.

BjornW 10mo ago

What an awesome project. It looks fabulous! Reminds me of the Dato Duo I have. The "Dato Duo" is also a synth aimed at kids. It allows 2 kids to play together. it is made by a Dutch company called Dato (https://dato.mu https://dato.mu). Their latest musical invention the "Dato Drum" had a successful Kickstarter and is shipping now. This drum machine allows even more kids to play together. PS: As the owner of a Dato Duo I can share you a little secret: it's also fun for adults :)

perelin 10mo ago
Love my Datos (also own the drum now)! My kids are jamming with them regularly. Only issue: my youngest LOVES the "Crush" button and just holds it the whole time. Not easy for noise sensitive parents :)

Waterluvian 10mo ago

If I have zero experience designing PCBs but wanted to do a similarly (non)-complex one, how much of a tall order would that be? In my completely made-up mental model, I'm guessing I just take the parts I've already breadboarded, look them up in some sidebar, and drag and drop them around, snapping to nice clean spacing, and then connect all the various pins together and have it automatically organize things? We're not going for perfect here. Just "Baby's first PCB" that at least works. And then when I have one designed, how much would it cost to get made and sent to me if I was okay if it took a month? But most importantly: how do I build personal confidence that I'm not shipping a potato off to be printed? Is there a community I could ask for a review from?

jmb99 10mo ago
If the board is small (10x10cm or less) it will be almost completely free, like single-digit dollars, through somewhere like JLPCB. So I’d say don’t worry too much about that, just jump in and try! As for actually designing, it’s a little more complicated than that but not by much. I did my first pcbs with KiCAD ~5 years ago by pretty much just guessing and googling where things were. Completely feasible if you have 0 background experience.
random_moonwalk 10mo ago
Hi, your mental model is essentially correct, though it took me a good few evenings over a couple of weeks to get the workflow down in fusion 360. The electronics retailer will usually have the footprint and 3d model available on the component page. You can then import it, define which pins you want connected to each other in the footprint and in the PCB editor you can drag the routes (wires) to connect them. Printing is way cheaper than I initially thought it would be - I paid £35 or so, including delivery and 5 of them arrived in 5 days. You can get cheaper delivery though. Also most of that cost is shipping and the setup fee - the marginal cost for each additional PCB print in the order is on the order of low single digit dollars. Tbh my circuit was fairly simple so I just took a bit of a chance (and some extra care wiring things up). I think there’s a subreddit where people give feedback though I haven’t submitted anything.
bluGill 10mo ago

solfox 10mo ago

Looks amazing! Reminds me of a funny reddit thread about a man who built a fiber optic star ceiling for his daughter. The top comment was "First child?". :) https://www.reddit.com/r/DIY/comments/8g8pce/fiberoptic_star_ceiling_in_my_daughters_nursery/ https://www.reddit.com/r/DIY/comments/8g8pce/fiberoptic_star...

Brajeshwar 10mo ago
And then the things you do to redeem your guilt for the second child is a whole interesting area.
- random_moonwalk 10mo ago
  That's what the drum machine module is for.
- sroussey 10mo ago
  And then they give up by the fourth. Guess which one I was, lol.
- Bengalilol 10mo ago
  Hi Brajeshwar (back to the old flashcoders days). Children grow up and in the end you get the full orchestra ^^
  - Brajeshwar 10mo ago
    Those were the days. It was blunt, wild, and erratic but we had fun.
- solfox 10mo ago
  When I first saw the starfield post, I had one kid. I was building her all sorts of cool stuff: brio table, custom childrens book, etc. So naturally, I disbelieved the assertion that my second child would get anything less than my first. Alas, the insight is spot on - for all your good intentions, the second child gets shafted. I think it's just one of those things you have to experience to get it.

fny 10mo ago

Great work! This brings back memories of futzing with knobs on a boombox as a kid. For your sake, I hope you built a heaphone jack.

random_moonwalk 10mo ago
Thank you! Unfortunately I decided to save that feature for v2!
- gus_massa 10mo ago
  Strong sugestión for v2: Add a hidden knob to regulate the max volume. Kids love to raise it to the max. (In a tablet, I had to secretly add some transparent tape between the speaker and the plastic cover case.)

gulan28 10mo ago

This is awesome. I had vibecoded something similar called https://chippytune.com https://chippytune.com for myself. Still working on wav support though

habosa 10mo ago

This is fantastic, as a hardware synth lover and a dad you’re making me pretty jealous.

ronbenton 10mo ago

Wow looks professional

fainpul 10mo ago

> A 3D-printed enclosure is fine for a prototype, but a real product likely needs injection-molded parts, which require expensive tooling. For kid-friendly toys, yes. But for older users not necessarily: https://teenage.engineering/products/po https://teenage.engineering/products/po

speedgoose 10mo ago
I have two of those. They are great additions to my drawers. One has a silicon case and is nicer to use though.
- NoSalt 10mo ago
  You say "they are great additions to my drawers". Is that because they suck, or is it that you don't have the time to enjoy them? (which I totally understand) I have seen these before and didn't know if they were worth the money. What is your opinion on them?
  - brudgers 10mo ago
    On one hand, $100 will buy a lot of hamburger. On the other hand, it's relatively low for a musical instrument and pretty easy to justify when if you suffer from gas. I am only speaking for myself, but I have a drawer of small musical electronics that I use occasionally. I bought them because I was curious.. I keep them because they are musical and not worth selling.
  - speedgoose 10mo ago
    I have the PO-12 (drum machine), and the PO-33 (sampler). They are somewhat limited but that can a good creativity booster. I don’t use them often because I’m not a great musician. I think they were worth the money, for sure.
elric 10mo ago
Wood is also pretty child friendly. But neither injection molding nor carpentry will protect a synth from a child dunking it in a puddle of water.

gwbas1c 10mo ago

Makes me wonder what the difference, in definition, is between a sequencer and a synthesizer? Is this really a synthesizer, or is it really a sequencer? Yes, I'm splitting hairs about semantics.

butlike 10mo ago
A sequencer is always in steps. A synthesizer has a signal generator and can modulate a single step. This toy is both a synthesizer and a sequencer, but since you cannot toggle the 4 steps off, it will always be a sequencer in addition to the synthesizer
PaulDavisThe1st 10mo ago
The answer to your question is "yes". It is a synthesiser AND it is a step sequencer.
dave_sid 10mo ago
Both
oidar 10mo ago
The linked project is both. A synth makes sounds, and a sequencer controls the sound over time usually with note on/off data. This sequencer has 4 steps before looping back to the beginning. To simplify, think of a sequencer as the music box drum and the synth as the tines in a music box.
strogonoff 10mo ago
A synthesizer is generally a higher-level ready-to-use product containing any number of oscillators, sequencers, and other circuits and bells and whistles under the hood. A device with an oscillator and a sequencer qualifies as a basic synth. At a lower levels you find modules like sequencer, oscillator, etc. They are generally not used by themselves: you plug a sequencer into an oscillator to make use of it, just like a standalone oscillator by itself simply makes a continuous noise that gets old quickly. A synth does that connection for you and exposes the controls. (To make things even more fun, the lines between lower-level audio modules are often blurred. For example, the difference between a sequencer and an oscillator can be best summed up as: the former is commonly designed for unipolar control rate signal change where you can specify exact level per step, while the latter is designed for bipolar audio rate signal change between two predetermined extremes—however, as the “designed for” hints, you could configure some sequencers to output a bipolar signal changing so fast it is audible, just like you could run a square wave oscillator so slowly that it becomes a 2-step sequencer.)

phplovesong 10mo ago

As a father to a daughter this warms my heart. Well done daddy! Points to you!

NickC25 10mo ago

that's great! may your daughter make great use of it! love the fact that your step sequencer even has a display to tell you what note you are adjusting to and from. i've always found that tuning synths and sequencers both analog and digital can be a pain because you can forget the note (or you don't have a good set of ears or perfect pitch) even if the result sounds good.

binary132 10mo ago

Totally rad! Makes me think about what kind of simple programming could be possible with a minimal HCI like this.

tapland 10mo ago

This is great. I’m going to start making something like this, but with some cut apple wood knobs, for my birds.

bitwize 10mo ago

The other day I came across a post on Facebook that was just some guy grousing that the new Teenage Engineering gadget looked like "a baby's activity center". And now we've come full circle: a baby's activity center that's actually not far off from Teenage Engineering kit.

afandian 10mo ago

Amazing the things we do for our little ones. I built a toddler-friendly keyboard for my son. He's still playing some form of piano 6 years later, no longer with his fists or feet. https://blog.afandian.com/2019/09/ux-for-toddlers/ https://blog.afandian.com/2019/09/ux-for-toddlers/

newtwilly 10mo ago
Beautifully done!
beAbU 10mo ago
Thank you for that closing paragraph in your article. Every time I read something online that tries to bend it into some "profound" lesson, or integrate it into the writer's personal brand, I throw up a little. This is most egregious on LinkedIn, and why I avoid that place unless I have to find a new job or something.

danvoell 10mo ago

This is awesome. Just awesome. Love that it looks like a baby toy and packs enough punch to get a kid about 20 years up the line of music understanding.

cjonas 10mo ago

I've been learning CAD, 3d printing, PCB design and brushing up on my embedded programming... all with the goal of being able to build toys for/with my son. It's incredible how accessible it is in todays world, made possible by these advancements: - incredibly powerful and cheap microprocessors (esp-32) - Fast, high precision desktop 3d printers - Affordable small batch PCB manufacturing - LLM's to advise on circuit design and help with embedded programming Would you have any interest selling a non-comm license to the PCB, f3d files and source code? My 1.5yo son would absolutely love this!

mcrider 10mo ago
Same, I recently got into Arduino so i could build a toy idea I had for my kid (a sort of "keepy-uppy" paddle game). I've always avoided Arduino projects because I don't like to code in my spare time (its my day job) and also learning how to wire things seemed daunting -- LLMs solved both of those problems for me (Claude's wiring tutorials are awesome and the code is simple enough that it can one-shot it). I also bought a Bambu A1 3D Printer and it is unexpectedly way more fun and useful than I thought it would be. I designed the toy in TinkerCAD and it printed out beautifully (I also have been printing out lots of other toys and yes, useful things for around the house and for other projects). Next steps are learning Fusion 360 and figuring out PCBs -- That also seemed daunting to me but its nice to see other amateur hobbyists are seemingly picking it up with not much difficulty.
- cjonas 10mo ago
  I highly recommend the "learn fusion 360 in 20 days" series on YouTube. I think I did it pretty causally in half that time. Then just find excuses to design stuff. After about a year of random projects, I can pretty proficiency draw most simple assemblies. This morning my son broke the battery hatch on his favorite toy and within an hour I had a replacement printed. (ducktape would have certainly been faster but where's the fun in that ;) One thing I would point out is if your interested in organic shapes that blender is the better tool to learn/use. Fusions surface modeling is pretty hard to work with.

JoeDaDude 10mo ago

Cool! Reminds of the Music From Outer Space synth in which the designer makes the claim that it "can actually get a child away from a television" and includes a video to prove it. https://www.youtube.com/watch?v=i6M_KrZByz4 https://www.youtube.com/watch?v=i6M_KrZByz4 MFOS Weird Sound Generator https://musicfromouterspace.com/index.php?CATPARTNO=WSG001&PROJARG=WSG2010%2Fwsg_page1.html&MAINTAB=SYNTHDIY&SONGID=NONE&VPW=2137&VPH=1063 https://musicfromouterspace.com/index.php?CATPARTNO=WSG001&P...

thenthenthen 10mo ago

Looks so nice! The sam is a midi synth chip right? Super cool. How/where did you get the knobs?

random_moonwalk 10mo ago
Thanks! Yes it's a little digital synth that receives MIDI. I used Chroma Cap knobs: https://store.djtechtools.com/products/chroma-caps-knobs-and-faders https://store.djtechtools.com/products/chroma-caps-knobs-and...
- thenthenthen 10mo ago
  Aah kool, i had one in a arduino format board, was great to cycle through all the instruments randomly + some sequence/chords. Instant Aphex Twin

oldestofsports 10mo ago

This is very impressive, it looks great!

BigTTYGothGF 10mo ago

The traditional approach is you give noisemaking toys to your niblings, not your own children.

random_moonwalk 10mo ago
This sounds like a lesson I’m going to be learning the hard way
- brudgers 10mo ago
  Good parenting is doing things the hard way. So why not go all in with a full set of acoustic drums?
  - bluGill 10mo ago
    Do you have $800? I'm trying to get my daughter a full set of acoustic drums (though odds are her brother will use them more even though he plays clarinet and she does percussion). I've seen full sets for as little as $30 - but it doesn't take much checking to realize they are not worth it even at that price. Good sets quickly cost more, but $800 is a good starting point for a set that isn't unusable.
    - brudgers 10mo ago
      Keeping in mind that you can’t buy a new Stradivarius… Maybe try Facebook Marketplace, Craigslist, etc. because drum sets take up space quality drum sets and other large instruments are often priced where moving the gear is part of the payment.
beAbU 10mo ago
We've been following this. Every nibling or even the offspring of friends received xylophones, tin whistles, hand drums etc. As long as it's not battery powered, it was on our "approved" list. They love us (the kids. The parents... not so much I guess). We have our first one due in a couple of weeks, and I guess we'll prepare ourselves for retribution!

warrenmiller 10mo ago

is it feasible to built one with a PCB? just straight to the UNO like your initial prototype - did that work ok?

NoSalt 10mo ago

This is absolutely FANTASTIC, and I am humbled by your mad skillz! My son and I are also fascinated by the sweet, sweet synth sound, but as I have no discernible talent, we went this route: https://www.sweetwater.com/store/detail/Nts1Mk2--korg-nutekt-nts-1-mkii-diy-digital-synthesizer-kit https://www.sweetwater.com/store/detail/Nts1Mk2--korg-nutekt... Which, unfortunately, has a HUGE learning curve in terms of operation.

rcarmo 10mo ago

This is great. I did a similar thing when my kids were young (revived an old, dead Kawai synth with a Raspberry Pi and sound fonts), but doing it with semi-discrete circuits seems a lot more fun.

broast 10mo ago

So cool, I think all kids would love this

bbhi 10mo ago

Looks like a fun project. I can highly recommend Teensy Audio Library for audio projects: https://www.pjrc.com/teensy/td_libs_Audio.html https://www.pjrc.com/teensy/td_libs_Audio.html

gregsadetsky 10mo ago
Mozzi (for Arduino) is also great! https://sensorium.github.io/Mozzi/ https://sensorium.github.io/Mozzi/

simgt 10mo ago

As someone who has never 3d printed anything, I'm surprised by how clean the case looks as opposed to what we usually see. Why is it so smooth?

TheSilva 10mo ago
Sanding and polishing, likely.
- bvm 10mo ago
  Nah, it just came out like that (i printed it :D) We experimented with ironing, but you can't see it in those views. The A1 is a pretty good printer OOTB. There were a few iterations on the case design though to optimise the edges.
gpm 10mo ago
The surfaces you're seeing in the pictures are almost all the "bottom" surface that was printed directly on the build plate. It basically just picks up the texture of the build plate and is otherwise smooth. That's actually a fairly bumpy build plate they printed it on (which lots of people like for aesthetic reasons). That said modern 3D printers are good at producing pretty nice parts these days, especially if you print with small layer heights. You might be underestimating the possible quality of 3d printed objects.

sgallant 10mo ago

My kids would love this.

woolion 10mo ago

Were you aware of the Dato Duo (https://dato.mu/ https://dato.mu/)? It's very cool for kids, except for the fairly steep price point. The advantage is that it's limited, so it greatly reduces the wall of difficulty to manage to get some 'nice-sounding' music (mostly the restriction to the pentatonic scale). However, kids still manage to find the most horrible-sounding settings, and insist on keeping them as is...

helsontaveras18 10mo ago

Wow, what an amazing demo for such a simple synth. Great work! If you ever start a Kickstarter, I’d be happy to donate. If it inspires some kid out there to get into music production, it’s a win for me :)

giancarlostoro 10mo ago

Would love something like this for my daughter, but with a max volume option she can't tamper with LOL

bigiain 10mo ago
That's a great reason to redesign it around an ESP32. So you can have an app on your phone that lets you control the volume over WiFi...

RobertWesner 10mo ago

I can't put into words how awesome this is. Perfect demo.

PaulHoule 10mo ago

Kinda funny but my adult son has taken an interest in guitars and keyboard and that has me working on MIDI routers with AVR-8 and building an ESP32 based synth module.

yzydserd 10mo ago

I was too fascinated by the different thumb nail lengths to concentrate much on the video.

random_moonwalk 10mo ago
I trained as a classical guitarist, so I maintain some longer nails on my right hand :)

rock_artist 10mo ago

What I love about this is how physical it is. So yeah, there's some board running DSP. but the design is amazing. It really relates to some recent posts also in HN about many objects loosing their physical UX. from an age of having buttons and tactical interfaces, everything became more touch based / app based which indeed cut price and allows easier updating. but also lacks some romance which is exactly what this device shows.

brudgers 10mo ago
Reminded me of a BlipBlox… https://blipblox.com https://blipblox.com
- bigiain 10mo ago
  Reminded me of Teenage Engineering's Pocket Operators: https://teenage.engineering/store/pocket-operators https://teenage.engineering/store/pocket-operators I have a few of those, and heaps of my friends gat sucked deeply into playing with them at the expense of whatever they actually came over for. "Nah, I'm not hungry. You should all eat without me, I'll just finish tweaking this groove." They're aimed (as the company name hints) as a little older than 3 year olds. One hint for the OP, it's so cool how you can plug those toys into each other in a chain, and have them all sync - so the percussion, base, and melody can all be programmed on threee different POs, and automatically play together.
  - yumraj 10mo ago
    What would you say is the best one to start with, say for a young middle schooler? Maybe best 3, in order?
    - bigiain 10mo ago
      I don't think it matters all that much. Any specific opinions are going to be more a natter of personal taste. Get one aimed at rhythm/percussion, one that has some bass/lowend sounds, and something to make melodies. I have a PO12, PO14, and PO16. If I was going to buy another one it'd be a toss up between the PO33 and the PO35. If I were starting from scratch I think I'd still get the PO14, I might get a PO24 or PO32 instead of the PO12, and I might get a PO28 instead of the 16. Or if said young middle schooler has access to sounds they can sample easily enough (like, say, Garageband on an iPad_ maybe jump straight to one of the sampling ones (PO33 or 35) for the lead/melody sounds.

mttch 10mo ago

This is great, i’d kickstart it, my 5 year old would love it.

Krisso 10mo ago

Dad of the year <3

tmilard 10mo ago

I'm not a kid. I still want it !

pragma_x 10mo ago
Same. It's a solid four-note ARP that sticks to a fixed set of musical keys. You literally can't make bad sounding music with this. A more grown-up version of this would be 16 notes, with variable length patterns (4-16?), and a "swing" function. A little bit of I/O mux under the hood and I bet this design could be expanded in that way. Or maybe you just daisy-chain multiple sequencers?
- brudgers 10mo ago
  This ends at Eurorack.
  - pragma_x 10mo ago
    It _all_ ends at eurorack. Especially my bank account.

chaosprint 10mo ago

Great finish. I was busy designing and soldering the prototype synthesizer during the summer, but I had to put it on hold because my baby was born in September. I had the same problem back then: injection molding is quite expensive to start. But you could consider a more creative approach: using a PCB directly as the panel, such as a TE's Pocket Operator. Korg also has this solution for some educational products. Alternatively, you could use 3D printing; there are many inexpensive services in China. CNC doesn't have the mold-making issue, but it's more expensive and doesn't seem suitable for children. Another interesting point: after my child was born, I didn't have much time for my sound work. But recently, I was surprised to find that I spend most of my time playing white noise on Glicol (http://glicol.org/ http://glicol.org/) and it works great for my kid. ``` o: noise 42 >> lpf ~mod 1 >> mul ~mod3 ~mod: sin ~mod2 >> mul 200 >> add 1000 ~mod2: sin 0.1 >> mul 0.04 >> add 0.1 ~mod3: sin 0.04 >> mul 0.3 >> add 0.8 ``` Good luck with kickstarter!

Joeboy 10mo ago

It's not kid friendly, but in case anybody's interested I just wrote up how I made a simple "hardware" synth by bodging together a Raspberry Pi Pico 2 and I2S audio module, total cost around £10 on Amazon UK. The hardware's very cheap and easy. The "default" synthesis is pretty simple but also pretty hackable (in Rust) if you want to customize it. https://github.com/Joeboy/oxynth/ https://github.com/Joeboy/oxynth/

afandian 10mo ago
Thanks for sharing! I did some similar playing around with an ESP32 and I2S a few years ago (lockdowns were an odd time). Where I seem to remember getting stuck was how to get the phase to line up, so that each sample looped at a zero-crossing point (which is different for each frequency). For the lazy, what did you do? https://gitlab.com/afandian/melodicornamuse/-/blob/main/melodicornamuse.ino https://gitlab.com/afandian/melodicornamuse/-/blob/main/melo...
- Joeboy 10mo ago
  I don't really understand your issue sorry, but my thing basically just writes the audio output to a buffer, and the DMA and PIO "automatically" send that to the I2S output. There's also some messing about with ping ponging between two DMA buffers to avoid gaps between each buffer write audio. I guess things might be quite different on the ESP32. Edit: Ok I glanced at your code, if I read it right it seems like you're writing sin waves into buffers at "init" time then copying the appropriate buffer at "run" time. Which is not what I'd do, but then I'm used to more luxurious devices. Maybe try using a fast sin approximation rather than the precomputed buffer table? https://bmtechjournal.wordpress.com/2020/05/27/super-fast-quadratic-sinusoid-approximation/ https://bmtechjournal.wordpress.com/2020/05/27/super-fast-qu... might be helpful there.
  - afandian 10mo ago
    Thanks! This was just some playing round years ago, so I don't remember much about it. I don't remember if calculating sin() at runtime was too slow, or I wanted to avoid polyphonic O(n) inside the buffer loop, or what. I bet it uses a LUT anyway. I much prefer your method of just rotating the phase!

dep_b 10mo ago

The korg monotribe is magic for kids

random_moonwalk 10mo ago

Thanks for all the kind words and feedback. There are some comments expressing interest in supporting a Kickstarter etc. If you're interested in receiving updates you can leave your email here: https://tally.so/r/Y55dXv https://tally.so/r/Y55dXv Thanks again - this was a bit of a surprise!

nixass 10mo ago
Seems like interest for your synth brought down Cloudflare! /s
markatkinson 10mo ago
Boet you broke the internet! I can't subscribe to updates :(
- random_moonwalk 10mo ago
  Ah the Cloudflare outage has hit my form!
- deleted 10mo ago
  [deleted]
jbl0ndie 10mo ago
Lovely project and a really great idea. Have you come across soft tooling for injection moulding? It's a lower cost, short run approach using much less durable moulds from various materials.
- random_moonwalk 10mo ago
  Thank you! I didn't know that was a thing - I'm going to look into it.
- jacquesm 10mo ago
  Before you have that working you'll have 3D printed a containerload of these ;) Besides the lack of flexibility if you want to make changes. I've used soft tooling for some projects but I was (1) never really happy with the results and (2) ended up breaking the molds quite often resulting in a lot of wasted material and expense. 3D printing is the way to go for projects such as these.

dinobones 10mo ago

This is such a good idea! Kids music toys are often just purely toys tap a button, make a sound... But the skill ceiling could be so much higher, offering the ability to learn and express themselves more. Awesome work.

amenghra 10mo ago
One of my favorite kids music toy is a mini piano where you have to replay one among 5-6 melodies (each melody is 5-10 notes that you have to memorize by ear — no lights involved) to unlock a little happy sound. This toy managed to keep both, dad and kid busy for a while.
moron4hire 10mo ago
For anyone who likes the idea of better music "toys" for their kids (i.e. not toys at all, but still easy to use) but doesn't have the capacity to build stuff like this, my kids and I love the Korg Koassilator: https://www.korg.com/us/products/dj/kaossilator2/ https://www.korg.com/us/products/dj/kaossilator2/ You can usually get them on eBay for USD$60 - 70. You do need to bring your own speakers, but a pair of cheap PC speakers are good enough, and it's a good start on creating a whole synth + effects chain. Speaking of which, there is also the Mini Kaos Pad, which is a dynamic effects processor: https://www.korg.com/us/products/dj/mini_kaoss_pad2/ https://www.korg.com/us/products/dj/mini_kaoss_pad2/ This one is a little more difficult to figure out for the kids as it is a "modifier" in the chain and they haven't quite wrapped their head around that concept yet. But still, it works great, has lots of features, and is really inexpensive for such a thing. And finally, they have a number of these mini-synths that are in the USD$30 - 50 range that are a ton of fun: https://www.korg.com/us/products/dj/monotron_duo/ https://www.korg.com/us/products/dj/monotron_duo/

TurkishPoptart 10mo ago

Good lord, you must have an amazing wife/support system to give you some peace while you designed this amazing toy.

random_moonwalk 10mo ago
I am very lucky in this regard, my partner is amazing indeed! Most of the work was at night, so I hopefully didn't disrupt her too much.

fabioq 10mo ago

What an incredible idea, I with every nursery to school had some of these!

ty_2k 10mo ago

Really cool project, super polished. The panda animation!

yigalirani 10mo ago

build it at scale and make a fortune

jeremydavid 10mo ago

Wow! Very cool. How hard would it be to create a "custom" sound, where you use the sliders to adjust the Attack Decay Sustain and Release?

evmaki 10mo ago

What a beautiful and charming project. Kudos for taking it all the way from zero to one with such a polished design. That's no small feat. I've built prototypes for eurorack and even with some simplifying constraints it's a lot of work. Best of luck with your Kickstarter!

amatecha 10mo ago

Ahh, this made me think of "Dato DUO", similar concept (though the Dato stuff is a little more complex): https://dato.mu/ https://dato.mu/

Bengalilol 10mo ago

I love the atmosphere, the object and the purpose.

mft_ 10mo ago

Hmm, very cool project and maybe just the inspiration I need. I bought a Baby Einstein Magic Touch Guitar for a friend’s daughter a couple of years ago, and while it was okay as a toy, it was disappointing as a musical instrument because the chords it plays are badly chosen. It’s basically impossible to play along with most songs. I’ve had the back burnered idea to buy another and improve it; maybe I will now, following a variation on your approach.

thomasqbrady 10mo ago

This is phenomenal, but my biggest question is (which is probably a more of a long-term one that comes from genuine curiosity/fascination, not doubt): does she use it/enjoy it? I'm so curious to see what happens over time. Does she learn the functions of these buttons, years before having words for what they're doing? Does she write some music? Does she grow up expecting things with knobs to be this interactive/creative? SO cool!

blauditore 10mo ago
3-year-olds actually have quite a vocabulary, so they can certainly talk about what the knobs are doing, maybe just not as accurately as adults. Regarding discovering functionality: The author mentions Montessori stuff, and the philosophy there is unguided discovery, "let them figure out by themselves". Not sure if that's how the author is planning to use this too, though.

nielsbot 10mo ago

Reminds me of the work of Love Hultén: https://www.lovehulten.com https://www.lovehulten.com He builds beautiful, colorful, retro-futuristic audio-visual art pieces Many are synths.

dimatura 10mo ago

There's a fun podcast by Arman Bohn/Distropolis (who himself has made some cool small-batch hardware synths) where he interviews makers of small hardware synths, https://open.spotify.com/show/30USGHPeGQ9ZyWQDyRnfcv https://open.spotify.com/show/30USGHPeGQ9ZyWQDyRnfcv might be of interest.

endorphine 10mo ago

Where would you suggest someone starts for building something like this. What kind of hardware would you suggest (preferably something with Rust!bindings). Is the one used in the original post a good starting point? I've minimal to no experience with embedded.

sunray2 10mo ago

Putting aside the beauty of both the synth and its purpose, what I'm curious about is the learning process in making this. The running theme is that you picked up several new skills 'from cold'. That in itself is impressive enough. How did you approach learning: - the necessary basic electronics; - PCB design; - 3D CAD; - your particular iterative process, among other things? I get the impression you built things incrementally, observed what happens and learnt via that feedback loop? Maybe others could share their own feedback loops, too.

random_moonwalk 10mo ago
I've been reflecting on this a bit. I found it very useful to have a well-defined project and focus the learning time on things that are necessary for completing it. Having a background in coding was useful because I find you end up developing a knack for isolating parts of systems and figuring out how to work on small parts that end up fitting together. I therefore focused initially on simply getting readings from a single potentiometer; if I could do that then I felt pretty confident I could read from four of them. If I could generate a midi message I was pretty confident I could send it to something that could read it etc. When I started on the PCB design I had a simple circuit already so it was a case of translating that onto a board. I didn't get too deep into any of the various parts but I found that it gave me a birds-eye view of the whole process and I now feel confident in isolating parts of them and 'zooming in' to them and refining them, building on the foundation I've developed.

evereverever 10mo ago

Amazing! Kids need more synths! My kids play the blip blop and the critter & guitari synth.

michaelhoney 10mo ago

So impressed by this, from someone with no prior experience. A1 hacker news experience, congrats

Geste 10mo ago

Oof, nice one ! I was looking for some synths for my less-than-two-years kid, after seeing their face light up when I fiddle with my Lofi 12 XT in front of them. I had all these criterias : -Something without any screens -Something simple enough -Something that could withstand some rough play I looked and looked, was considering proper Aira Compact synths, but ended up with the antiquity of the Bliptronic 5000 from Thinkgeek. https://youtu.be/6rCfhF-fNb4 https://youtu.be/6rCfhF-fNb4 They love it, the buttons are beyond fun to them, but the knobs are quite hard to turn for a little kid (1st world problem, I know) I felt they were too young for a Blipbox, and I also bought an Orba 2, we'll see how that one goes. But I dreamed of such a device, with easy to turn knobs, and colorful display, something simple to modulate sounds and just hear melodies. Seeing how you created it is both inspiring and discouraging, as someone with limited free time and electrical knowledge, but, you never know !

freshnode 10mo ago

Well done. This is really inspiring.

_adamb 10mo ago

As a EE nerd, I love this project. As a parent, it's the sort of toy I want to smash as the repetition drives me insane. What should I make that captures the awesomeness of this project without the insanity? Hmm...

doppelgunner 10mo ago

[dead]

findthebug 10mo ago

love this!

beAbU 10mo ago

I want to commend you for making this actually musical. Too often these basic synths aimed at kids are little more than a noise maker unless you really know what you are doing. My spouse and I are into music and we are pretty serious choristers. We have our first little one on the way this December, and we definitely want to expose them to making music from a very young age. Your synth looks like an excellent way to do that, as it does not seem possible to get it in a state where it's just making horrible noises, every state will be some new pleasant little jingle. Bravo!

johntash 10mo ago

My mind jumped to synths from the Fallout games, so I was disappointed to find something else, but it's still pretty cool!

dazamarquez 10mo ago

Is the plastic and other materials you used safe for children?

Dowwie 10mo ago

We have similar interests! I've been working on a DIY animatronic project that is mostly vibe-coded using Sonnet 4.5. It's my first electronics project. So far, I got the Ultrasonic Sensor to trigger led when object is less than 2 feet away. I set up a sound player and the components fried when I started the device. I have to redo all of the wiring for the sound setup again. I only have one of three sound modules that isn't bricked. The comments in this thread reveal a community of parents who are aspiring builders of high tech devices for their children. I think this community need a discord.

jacquesm 10mo ago

There's a lot of talent on display here. For someone who has never done any of this I'm so impressed with the degree of finish and care as well as the functionality of the device. It even sounds pleasant. Dad of the year award!

Rioverde 10mo ago

Just Amazing !

rickygman 10mo ago

[dead]