Electronic Harp Mandolin Prototype

April 23rd, 2024
emandoharp, jammer, mandolin, music, tech
While I'm not really at a clear stopping point, I wanted to write up my recent progress with the electronic harp mandolin project. If I go too much further without writing anything up I'm going to start forgetting things. First, a demo:

Or, if you're prefer a different model:

Since last time, I:

  • Fixed my interference issues by:

    1. Grounding the piezo input instead of putting it at +1.65v.
    2. Shielding my longer wires.
    3. Soldering my ground and power pins that I'd missed initially (!!)
  • Got the software working reasonably reliably.

  • Designed and 3D printed a case, with lots of help from my MAS.837 TA, Lancelot.

  • Dumped epoxy all over the back of the metal plate to make it less likely the little piezo wires will break off.

  • Revived the Mac version of my MIDI mapper and made a cut down version that is designed to drive a wind instrument synth (code).

While this works, it's a little bulky for attaching to the mandolin. I also don't like having a bunch of wires running from the teeth to the computer and that I only have thirteen of the eighteen inputs hooked up. I've also been enjoying playing it with my fingers, in more of a piano orientation. I decided to make a new version that's all a single board:

The squares show where the "teeth" will go.

I've prepared a new batch of eighteen pluck sensors:

Sanding them smooth was a good fit for watching the kids at the park.

I'm a bit nervous with this design that something will break and it will be hard to repair because it's all on one board, but it's got to be better than the giant blob of epoxy in the v1 design.

If this works well I might make a case for it where only the teeth poke out?

Comment via: facebook, lesswrong, mastodon, substack

Recent posts on blogs I like:

You can't join the secret inner circle of cool effective altruists

I, and a lot of other people I know, seem to believe something like this:

via Thing of Things August 11, 2026

Microfictions 2

A few more microfictions, still no LLMs.

via Evan Fields August 7, 2026

Using AI to analyze life patterns

If you’re anything like me, you may have a lot of notes from various introspective activities – annual / monthly reviews, worksheets, therapy notes, etc. Often these notes are just gathering dust in a paper folder or some forgotten corner of Google Drive.…

via Victoria Krakovna July 30, 2026

more     (via openring)