Older readers may remember the Stylophone, a small battery powered electric organ using conductive PCB pads and a stylus to create notes. The simple multivibrators in those instruments made them monophonic, but here in 2021 we can do better than that! [Sjm4306] has gone the extra mile with a PCB organ, by making a capacitive-touch instrument that boasts four-note polyphony.
At its heart is an ATmega328p whose software sports four tone generators that each emerge on a different pin. These are summed using a set of 100 Ω resistors and fed to a tiny speaker. Power comes from a CR2032 lithium cell, and he notes that a higher voltage delivers more volume.
The full story is detailed in the video below the break, along with a bit of four-note polyphonic action. We’re guessing that this instrument would sound sensational when hooked up to a reverb unit.
Hmm, I wonder how software-based tone generation would compare with hardware-based on this platform.
For those who have never seen a Stylophone:
https://www.youtube.com/watch?v=mraFtzNbmJQ
For those who can’t imagine it’s stylistic intonations being useful in a musical setting:
https://www.youtube.com/watch?v=yTOSXc4su8c
Wow! Amazing!! Just found it for £26 in the UK…
https://www.amazon.co.uk/Stylophone-Original-Pocket-Electronic-Organ/dp/B000SKHSRU/
Reminds me of this:
https://hackaday.com/2016/12/11/tiny-ts-just-how-small-can-a-playable-synethesiser-get/