Octasonic 8 x HC-SR04 Breakout Board (2017)
I originally created this board for a robotics project, but then realized that with 8 sensors, it was well suited for musical projects, such as the Ultrasonic Pi Piano.
I sold these boards on Tindie for a while, but I no longer have the time or motivation to do that.
It is possible to order pre-made boards directly from OSH Park here, but please note that I am not able to provide any technical support.
Here are some archived repositories containing design files and source code. Feel free to fork these and create derivative works.