chipweinberger

8 ms·

1.
by chipweinberger 2mo ago
The app is not required if you access the midi files from the sd card. You don't even need to install it. The app is optional, and its for browsing your library. Think of it like the Photos app but for MIDI.
2.
by chipweinberger 2mo ago
Counterfeit != clone. I welcome competitors. They can help grow the pie.
3.
by chipweinberger 2mo ago
If you consume power over USB-C, 2 resistor are enough. But for providing power over USB-C, you generally need a dedicated IC to handle VBUS switching. It wasn't worth it. Also, once you ship a consumer product with a USB port on it,
4.
by chipweinberger 2mo ago
I appreciate the critiques! First, so far, there have been 0 failures in the field. My email address is on the website, the app, and the first page of the instruction sheet, so I'd probably know if there were. But since it's fun
5.
by chipweinberger 2mo ago
500 units was my first run, and it worked out really well. None of the suppliers complained about that order size. I recommend starting with a smaller quantity until you've validated the market. The "economies of scale" betwe
6.
by chipweinberger 2mo ago
The device does not require the app. It still records MIDI 24/7 to sdcard. It's more the opposite. The app requires a genuine device.
7.
by chipweinberger 2mo ago
Will do a write up on injection molding and anti-counterfeit!
8.
by chipweinberger 2mo ago
Not technically custom, but made to order (I gave them a spec sheet). If they had reasonably priced connectors on LCSC or DigiKey, etc, I would have used them!
9.
by chipweinberger 2mo ago
The marketing answer: all lower-case looks modern and opinionated The real answer: I got tired of deciding what should and shouldn't be capitalized. Sounds easy but it gets ambiguous fast. I'll revisit this decision at some point.
10.
by chipweinberger 2mo ago
I don't entirely disagree. Just one sample point. But there are certainly much more simplistic hardware products out there. I'm often envious of them. Here's a good example: https://duckduckgo.com/?q=brick+s
11.
by chipweinberger 2mo ago
Yes the anti-counterfeit is primarily app enforced (though entirely offline). I do use the firmware encryption features of the ESP32-S3, whatever that is worth, and the firmware is tied to the HSM.
12.
by chipweinberger 2mo ago
Ahah good eye. It was only 4 blocks down the road! I too was surprised by how well a single cord worked to balance the 45lb boxes.
13.
by chipweinberger 2mo ago
Android too! Built with Flutter. Flutter is great highly recommend it.
14.
by chipweinberger 2mo ago
This is very flattering. Thank you.
15.
by chipweinberger 2mo ago
3 main components: flashing, provisioning keys, hardware testing. Nearly every component gets tested: sdcard, clock, battery, anti-counterfeit IC, led, buzzer, the tactile-switch!
16.
by chipweinberger 2mo ago
Yes I've seen a few people mention that! All of the best MIDI hardware recorders are ancient, for whatever reason. Well, apart from Jamcorder ;)
17.
by chipweinberger 2mo ago
It sort of is. I'm at an annoying scale where most 3PLs don't want to deal with me yet. At the same time, it doesn't take much time at all, and is a good excuse to get out of the house!
18.
by chipweinberger 2mo ago
I started with having watched ~100 hours of EEVBlog :) Electronics, PCBs, CAD, injection molding was all new to me.
19.
by chipweinberger 2mo ago
They should just work! You can replace the soundfont that the app uses with your own too.
20.
by chipweinberger 2mo ago
IMO it's better to ship preprogrammed ICs to the factory, so you can do your secure burning in-house.
21.
by chipweinberger 2mo ago
These numbers do not include ESP-IDF :)
22.
by chipweinberger 2mo ago
I chose to do FCC only and CE self-certify. If you use pre-certified radios it's not as expensive as you think. $5K should be plenty if you ask around. Just make sure you design your board so you actually pass, and don't let the l
23.
by chipweinberger 2mo ago
I'm using an STSAFE chip - the same IC they use in StarLink terminals. Essentially the digital equivalent of a holographic barcode. I have some other protections too. e.g. Random 128-bit per-device IDs / product-keys. iMessage use
24.
by chipweinberger 2mo ago
The app is about 85K lines: device connectivity, first-time setup, syncing, MIDI playback and visualization, library management, audio/video export, and OTA workflows. The firmware is about 110K lines: MIDI recording + streaming, USB,
25.
by chipweinberger 2mo ago
Spending too long on the firmware. I almost ran out of runway. I should have cut features faster. And I should have built the firmware cross platform so I could run it my local machine. Every compile + flash loop took 2+ minutes.
26.
by chipweinberger 2mo ago
I'll be sticking around in the comments so feel free to ask questions. AMA!
27.
What I learned selling 2,500 MIDI recorders: Hardware is not so hard(chipweinberger.com)
552 points by chipweinberger 2mo ago|257 comments
28.
by chipweinberger 2y ago
The D-Link DSR-150 was released in 2012 It was the first information I wanted to know, but it wasn't in the article.
29.
by chipweinberger 2y ago
Yes you can do that. Buy a standard midi to usb adapter (~$20), then do: piano -> (usb) -> Jamcorder -> (midi out) -> adapter -> (usb) -> pc It should give acceptable latency for real-time recording.
30.
by chipweinberger 2y ago
made improvements. It's now about 12ms constant. Usable for real-time playback.

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