[sdiy] use pc psu's as EMI chassis for synth modules

cheater cheater cheater00 at gmail.com
Fri Nov 26 21:32:53 CET 2010


Hi guys,
I've had a look at those old broken power supplies that will never
come to life, and I have had the perfect idea - you can use the
chassis for something nice! It's much shorter than one dotcom unit,
and a bit wider. More like 1 1/2 dotcom unit wide, or just under 2U of
MOTM. Still, most of the modules could probably fit in very easily.

Pro's:
- the module is nicely shielded from others and from outside interference
- the module gets some nice thermal stability
- if the module gets very hot, you can mount a Noctua P12 fan
(inaudible) and cool it
- the module is sturdier. It can sit on a shelf without you fearing
that the fragile PCBs will be destroyed.
- the module doesn't have wires sticking out! Installing new modules
and messing about inside a synth while it's turned on is not a problem
anymore
- generally, electrical safety is a big plus.
- you get a nice, sturdy frame for your module.
- the metal is usually just thick enough to be sturdy, but it's thin
enough to be easily punched.

Cons:
none


OK, those things are big, but then you don't have to use em for every module.

Regarding panel size etc: you can have one of several options:

1. use this size as your modular's panel size. Easy.
2. Dotcom: Use a cheap plastic panel and mount it to the chassis
stand-offs of about 1". This does two things: it gives you space to
mount front-panel controls; and additionally, if your module
front-panel is not as wide as the ex-powersupply chassis, you can
mount another, shallow, module next to it
3. Dotcom: use a cheap plastic panel and simply screw it onto the chassis.
4. Dotcom: take one row of your Dotcom chassis, and fill it with
modules of exactly this height. Use the remaining space for mults etc.
5. Eurorack: The side plate is slightly higher than eurorack. It's
also exactly 8 cm wide. Use the thing as a portable 4U eurorack synth.
Or, if your modules are not deep at all, then you can use it as 7U.
There's enough space there to house a small PSU as well, based off
e.g. a couple laptop power supplies (they have very flat toroids).
Even better, you get an IEC plug, and usually a fuse holder, so that
you don't need to take care of that.
6. Fracrack: same as Eurorack. Houses 1U of a deep module, or nearly
2U of fairly shallow modules. Having a tiny amount of overhang
(0.125") on the side shouldn't bother anyone.

Happy hacking!
D.



More information about the Synth-diy mailing list