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What I learned selling 2,500 MIDI recorders: Hardware is not so hard

chipweinberger.com

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Re: What I learned selling 2,500 MIDI recorders: Hardware is not so hard

#221

Post by aleph-z »

Congrats! Happy for your success. Your mix of ingredients is impressive (the hardware alone is probably simple). Your product idea came from actual personal need (validation!), and you are able to tie the hardware to your software to widen the moat -- which is great.

Your anti-counterfeiting tech hopefully / probably prevents your Chinese manufacturers / suppliers / related entities from free-riding on your work. (If your volumes start hitting say 50K+, things may change, you may be entering dangerous territory then, so I'd suggest you spend some time on beefing up the moat).

Good luck towards 10K volume!

Re: What I learned selling 2,500 MIDI recorders: Hardware is not so hard

#222

Post by xp84 »

BobbyTables2 wrote: post #217
tmp10423288442 wrote: post #188

Earlier quoted context omitted.

>your JS is too big, you can't ship until you get it under 50 kB Back in the glorious past, the iOS App Store either didn’t allow apps larger than 100 MiB, or at least forbade them from being downloaded over mobile connections. There’s an old blog post/Twitter thread you can find on Hacker News where an Uber engineer describes the challenges they faced in trying to keep their app under that limit. They were also rewr…

It still boggles my mind than such limits are a problem. Sure, a game with graphics and sound could easily burn past that. But for a “boring” ride hailing app, it’s still beyond my imagination. Microsoft Word was something like 8-10MB in the Windows 3.1 days. WordPerfect was about the same and even had a grammar checker. The entire damn PC with DOS, Windows, and Word was 30MB. We’ve fallen so far, we mistake the dark…

There isn’t all that much actual first-party code in these apps, but if they made a “Hello World” but kept the same third party library deps, they’d be starting at 300MB, and once they add all the visual assets that’s another 200MB… I have a ton of apps on my phone that are absurdly large. Like Gmail is 706MB. The Gmail app for iPhone could not fit on a CD-ROM. A plain mail client. Compared to that, Facebook at 461MB is looking quite slim.

Overcast is 37MB.

Re: What I learned selling 2,500 MIDI recorders: Hardware is not so hard

#223

Post by invictati »

chipweinberger wrote: post #98
illwrks wrote: post #94

Earlier quoted context omitted.

My guess is that it’s on the software side partnered with the app.

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.

Oh good, you're not pulling a Cricut where the app interactively proves to the cutter that it has an AES key and then encrypts all the G-code with it before transmitting over Bluetooth.

Right?

Re: What I learned selling 2,500 MIDI recorders: Hardware is not so hard

#224

Post by ColdStream »

BobbyTables2 wrote: post #217
tmp10423288442 wrote: post #188

Earlier quoted context omitted.

>your JS is too big, you can't ship until you get it under 50 kB Back in the glorious past, the iOS App Store either didn’t allow apps larger than 100 MiB, or at least forbade them from being downloaded over mobile connections. There’s an old blog post/Twitter thread you can find on Hacker News where an Uber engineer describes the challenges they faced in trying to keep their app under that limit. They were also rewr…

It still boggles my mind than such limits are a problem. Sure, a game with graphics and sound could easily burn past that. But for a “boring” ride hailing app, it’s still beyond my imagination. Microsoft Word was something like 8-10MB in the Windows 3.1 days. WordPerfect was about the same and even had a grammar checker. The entire damn PC with DOS, Windows, and Word was 30MB. We’ve fallen so far, we mistake the dark…

I don't want to justify the space too much, but things like the Uber app are kind of amazing.

While the base functionality is fairly simple in terms of find location > send car + all the courier and different varieties of what they do. It manages do that while working in 70+ countries over 15,000 cities with multiple different languages and payment vendors and it is all done via a single application.

That is pretty neat.

Yes, it is still very bloated but it does a lot more than what it initially looks like.

But yes, I am endless impressed when you come across a binary that is tiny. Like a text editor that is 14KB, sure it is simply but it doesn't need to be anything more for most people.

Re: What I learned selling 2,500 MIDI recorders: Hardware is not so hard

#225

Post by Suppafly »

Max-q wrote: post #219
em3rgent0rdr wrote: post #162

Earlier quoted context omitted.

> "actual regulations...emissions" yeah, and looking at their board I see they use one of "ESP32-WROOM" modules, which has the wifi & blutooth & antennae (pre-certified by Espressif for FCC, CE so itself doesn't need testing) & flash & processor (which even has its own RC oscillator), which takes care of a whole ton of difficult stuff so all the designer needs to do is plop that module down and power it up and wire s…

The pre certified module do not exempt the product from testing. It only means that you don’t have to do the conducted testing and that it’s a higher probability for passing the other tests. There are still lots of chances to fuck up and a full radiated test of the product is required.

>and a full radiated test of the product is required

legally?

Re: What I learned selling 2,500 MIDI recorders: Hardware is not so hard

#226

Post by Suppafly »

ColdStream wrote: post #224
BobbyTables2 wrote: post #217

Earlier quoted context omitted.

It still boggles my mind than such limits are a problem. Sure, a game with graphics and sound could easily burn past that. But for a “boring” ride hailing app, it’s still beyond my imagination. Microsoft Word was something like 8-10MB in the Windows 3.1 days. WordPerfect was about the same and even had a grammar checker. The entire damn PC with DOS, Windows, and Word was 30MB. We’ve fallen so far, we mistake the dark…

I don't want to justify the space too much, but things like the Uber app are kind of amazing. While the base functionality is fairly simple in terms of find location > send car + all the courier and different varieties of what they do. It manages do that while working in 70+ countries over 15,000 cities with multiple different languages and payment vendors and it is all done via a single application. That is pretty n…

>It manages do that while working in 70+ countries over 15,000 cities with multiple different languages and payment vendors and it is all done via a single application.

I'd assume almost all of that is done server side though. Most likely the app is mostly just a wrapped website with some gps and notification code on top.

Re: What I learned selling 2,500 MIDI recorders: Hardware is not so hard

#227

Post by Suppafly »

DavidPiper wrote: post #61

Very happy JamCorder customer here. I've started playing in improv shows since I bought it too, and it's nice to have those on record! It's rare that I come across a product I have literally zero complaints about, or any feedback to offer. Even my concern that it was tied to an app that might disappear one day is of course covered by the fact that it's all just MIDI files on a card. Thank you so much for making this,…

>Even my concern that it was tied to an app that might disappear one day is of course covered by the fact that it's all just MIDI files on a card.

I was sorta surprised when the blog mentioned it was like 200k lines of code for an app. I wouldn't think you'd even need an app for something that puts midi files on an sd card.

Re: What I learned selling 2,500 MIDI recorders: Hardware is not so hard

#228

Post by peteforde »

elictronic wrote: post #207
peteforde wrote: post #125

Very happy to hear about your success! I'm curious to hear more about your anti-counterfeit strategies beyond just enabling encryption. I'm curious if you feel like anti-counterfeit and open source firmware are mutually exclusive. I made the choice to embrace an open firmware approach on my project while keeping the hardware closed, while knowing that if someone tries hard enough they can completely reverse engineer…

You don't need an X-ray for a board this simple. Every component has well defined input and outputs. Give a mildly competent freshman EE student or high quality high school student you could have the board recreated in a few days. Low product quantity and low quality/fake products resold on amazon from AliExpress are the biggest roadblocks at this point. The juice isn't worth the squeeze.

Right... except I'm asking so that I can apply his techniques to my PCB, which you know nothing about.

Re: What I learned selling 2,500 MIDI recorders: Hardware is not so hard

#229

Post by jynsnsns »

Suppafly wrote: post #225
Max-q wrote: post #219

Earlier quoted context omitted.

The pre certified module do not exempt the product from testing. It only means that you don’t have to do the conducted testing and that it’s a higher probability for passing the other tests. There are still lots of chances to fuck up and a full radiated test of the product is required.

>and a full radiated test of the product is required legally?

Depends on the legislation, but for most markets yes

Re: What I learned selling 2,500 MIDI recorders: Hardware is not so hard

#230

Post by negative_zero »

nomel wrote: post #201
ost-ing wrote: post #189

Earlier quoted context omitted.

Im not an expert in emissions testing but pretty sure it still needs CE certification testing. The module shouldnt cause any problems providing that the firmware for the transmitter is configured properly, and is placed sanely in the enclosure, but the entire product must still undergo the relevant testing for 2.4GHz emitters. Just because you use a certified module doesn't give you a free pass.

> but the entire product must still undergo the relevant testing for 2.4GHz emitters. To be fair, it's unintentional radiator testing that's required, rather than everything the module had to go through as an intentional radiator . So, it is a "free pass" for nearly all of it, and a much cheaper one, since you don't have to use a costly FCC accredited lab.

Modular Approval is an FCC thing only. CE doesn't have it.
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