[sdiy] Synth Electronics

[Neil Johnson]

Ben Bradley wrote:
> Another good book from back then is "Musical Applications of
> Microprocessors" 2nd. edition. It has a remarkable amount of analog
> synth circuitry for a book on microprocessors, even though some of it
> is "discrete" ADCs and DACs as things were done back then.

One of our members has mint new copies for sale and I believe ships worldwide.

> You mentioned Sound Semiconductor

Check out their website: https://www.soundsemiconductor.com

> You
> mentioned Sound Semiconductor - one thing you might want to do (if
> this is to be a commercial product) is make sure at least one other
> maker of chips can be used, if not drop-in replaceable then at least
> by switching a few jumpers, so you don't end up with a lack of source
> of parts.

Outside of common parts like opamps once you use specialised
components then easy dropins are very unlikely.  In reality the only
options you have are clones.  For example, the original Analog Devices
SSM2164 has been cloned both by CoolAudio and Alfa Rpar, and then
later SSI re-issued it with some internal improvements which generally
make it compatible except in some applications which depend on certain
features that are not copied.  Same with things like the CEM parts or
original SSM parts.

If you want to learn about analogue synthesizer circuits I would
suggest looking at the ASM-1 VCO, which is easy to build and gives
great results, and generally uses widely available parts and is quite
tolerant of component choices (e.g., opamps, etc).

Cheers,
Neil