[sdiy] In praise of the ATM STM32F303

[Olivier Gillet]

> Charge pump generating higher voltage V+ and V- rails for the audio op amps from the Usb voltage input,
>
> -Richie,

I've seen this before in another product... It's explained here:
http://www.electroons.com/blog/2013/01/max232-for-negative-dc-voltages/

The chip is widespread enough to be cheaper than dedicated charge
pumps (LT1044). Works well for small amount of current and you get the
two rails!

Regarding the reverb: The reverb in Clouds uses 32k of RAM, it's the
standard 4x AP + 2x loops of (2 AP + 1 modulated delay) feeding each
other.
https://github.com/pichenettes/eurorack/blob/master/clouds/dsp/fx/reverb.h