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This is cool!

I want to try to build a hardware midi keyboard using mechanical hall effect switches like this: https://mechanicalkeyboards.com/products/wuque-studio-dash-5...

There's a few physical keyboards out there but many are super super expensive.

Sound is not quite right - C## should sound like D but it’s slightly off.

This would be great for Klingon Opera :) https://www.youtube.com/watch?v=1LjcBv-OWtQ

Now the Lumatone

https://www.lumatone.io/

Mike Battaglia plays Scarborough Fair in 31-tone equal temperament

https://www.youtube.com/watch?v=HJKB1_gvhLE

I'm impressed how responsive the keys are! Will definitely be checking out on desktop if I can see how the audio rendering code works (unless someone here already knows). I presume the audio synthesis API and ontouchstart but maybe there's something clever in addition like prerendering the audio samples rather than synthesising them on press

Maybe it also helps that I've got a headphone jack plugged in instead of the Bluetooth I'm used to from listening to things during the day, but even so, my touchscreen just doesn't feel this responsive normally, including in games. It's on my list of things to check the delay of, but since my phone's 960 fps camera is the equipment I use to check that, it is a bit tricky

Edit: ontouchstart calls noteOn method https://github.com/wcgbg/terpstrakeyboard/blob/03d526a0ed5c7...

This eventually calls into audio api start with 0 delay https://github.com/wcgbg/terpstrakeyboard/blob/03d526a0ed5c7...

The data to play was retrieved from the server (based on the instrument you selected) and parsed ahead of time https://github.com/wcgbg/terpstrakeyboard/blob/03d526a0ed5c7...

It loads samples at four frequencies and plays the nearest one at the appropriate rate (proportional to the target frequency) https://github.com/wcgbg/terpstrakeyboard/blob/03d526a0ed5c7...

The settings.audioContext variable is simply an instance of the web audio API as expected (with a fallback to support Safari/webkit) https://github.com/wcgbg/terpstrakeyboard/blob/03d526a0ed5c7...

This gainNode it's connecting is just about playback volume it seems https://developer.mozilla.org/en-US/docs/Web/API/BaseAudioCo... and "audioContext.destination", MDN says, you can think of as a speaker device

So nothing too special here: of course preloading server data but then simply creating a new sound source during ontouchstart is enough. I guess delay in other software comes from the extra cruft they have such as big libraries (and Bluetooth, in the cases where I use that), not from any actual delay in touchscreen or audio rendering

Pretty cool

First thing I did when I started playing with LLMs was vibe code a bunch of shitty virtual instruments. Roll your own, folks! Good fun.

Fun fact, anyone with a surname that ends with the -stra or -sma suffix has their origins in Frisia [0], a region in current-day Netherlands and Germany that retained their independence in the Roman era. Terpstra specifically refers to someone living on a terp, an artificial hill (because there's no hills in the Netherlands lololol) that people would live on or retreat to with the intermittent floodings.

This in turn is why the Netherlands is so big when it comes to dairy and cheese; grass was one of the few things that would grow consistently and survive the floods, cows eat grass, cheese and butter can be preserved to last through winter, etc.

[0] https://en.wikipedia.org/wiki/Frisia

TIL MacBook keyboards only send 6 key presses at once.

Somehow I cannot open the website.

I've been trying to design a keyboard that can be used with the feet - something that I can play like dance dance revolution, while playing something else with my hands (mandolin), thus making me a one man band. Figuring out what a good layout would be is the first step and so far everything I've thought of either lacks useful notes, is too big to reach useful notes, or the keys are too close together. If anyone has ideas on how to do this I'd love help. (or better yet do this as I don't have must time to work on it)