Prototypes from PCBWay: High Quality, Amazing Support and Communication

For ongoing experimentation with my "Magent Music" project, I designed this proto-keyboard in EasyEDA's online designer tool. I decided, this time, to try out PCBWay as the fabricator of my design. The overall results were excellent. Here are my impressions:
Fast deliveryAmazing communication and supportClean, well-made PCBs

And here's a glimpse of what I am doing with my shiny, new PCBs:

Overall, my experience with PCBWay has been 100% positive. I'm having lots of fun using my recent PCBs and look forward to making more.

CV/Pitch Controller Developments

Errors and EvolutionIt was last last protoboard. It was most of the last general purpose diodes, and I put them in the wrong place. But more importantly, I needed an excuse to try my first SMD order. Furthermore, I felt like I could streamline a few things about my processes, both technical and promotional. The hasty error propelled me forward. I calculated my voltage dividers more closely:

Better Design: TwelveyI immediately did a few things: 1) I made updated the project - which is public and cloneable and Public Domain; 2) I wrote up a description on Hackaday; and. 3) I made some available for sale.

Audio Tests: Pushbuttons and Reed SwitchesI then tried a couple proofs-of-concept - one with salvaged buttons, the other with magnetic induction switches:

I continue to find that starting out by imagining the finished product leads to more and more experimentation related to the best design. As yet, I have not discovered my best designs, but I am excited to have made progress and gained kn…

1V/oct CV/Pitch Keyboard controller

Building a CV Controller (Again) Over the past few days, I've been playing with the idea of a 12-key CV keyboard. I've built other CV controllers before - including a mini repurposed keyboard segment atop a custom voltage divider circuit, and a fully-weird follow-up, complete with joystick. For my next foray into keyboard CV/Pitch controllers, I am revisiting the voltage divider approach.

Preliminary Specifications The chief difference this time is: I'm actually understanding the required math a little better, so I'm trying a little more diligently. First, I sketched out my ideas (above) and did a little research. Then, experimentally, I started plugging resistor values into a spreadsheet (below) using a formula I found. I want to use the 1V/Octave method, and I have a custom power supply that delivers 4.5V (actually, about 4.23V, according to my measurement thereof).

Again, experimentally, I assumed that my "R1" could be a 1K resistor. I then calculated the…