[sdiy] Powering a second bit of kit from same PSU (wiring options)

[Nathanael King]

> (Well, I'm assuming a simple 2 pin PSU - if you have a "real" PSU with
> +/GND/-, things are looking much more benign.)

If the proposed power supply has plenty of current for two boxes, it's
probably not a wall-wart :)

Besides, if:
"Say for example, both units use a voltage regulator for an artificial
center ground between both power pins, and use that as a signal ground.
If both centers are not at the same voltage, you may have kind of a
short circuit via signal ground."

That would be done in the individual boxes/units/synths/etc and the
only thing that would be affected would be overall current draw. The
grounds are otherwise inherently isolated by the voltage dividers and
regulators. Well, not isolated, but drawing current back through the
supplies. This is the whole reason NOT to use a DC wall-wart, because
the power is usually dirty, and hard to calculate overall current draw
(and therefore supply voltage). At least with an AC wall-wart, the
supplies are symmetrical. So, as you draw more current the supply
voltages decrease equivalent amounts.

As you said, this is all besides the point because if it's a
legitimate power supply (linear transformer based design) it should be
capable of driving anything you want. As long as you don't exceed it's
current specifications, of course.

I say go for it. I'd run the other box power cord separately with
similar gauge wire. If your individual boxes aren't equipped with a
fuse, that might be a good idea.

Nate