I decided to aggregate my two biometric modules — the SoundMachines Brain Wave interface and the ADDAC Systems Muscle Sensing — into a small Eurorack case that would also hold some oscillators and other modulators to be controlled. Looking around, I found this Pittsburgh Modular Cell 48 Case.
It comes with an analog power supply and wall adapter.
I’ve seen different specs on this supply, but it seems to have +12V @ 900mA, -12v @ 900mA, +5V @ 500mA of power. The +12V uses a standard three terminal regulator, LM7812. Oddly, it is putting out 12.4 volts. The -12V and +5V outputs are very close the expected voltages. Since the regulators don’t use heat sinks, they won’t be able to deliver the full 1A of current. There’s no ventilation in this case, so I wonder if heat will be a problem. The wall adapter puts out 15V and I would not try to substitute a higher voltage one.
Power distribution is by two strips with four keyed headers each. Notice, however, that there is a third connector on the board that can be used as an alternative location for one of these. This could come in handy, depending on module depths. I had it plugged that way at one point.
The photos show the back side of the case, where the power inlet and switch are located. I added a black banana jack to carry ground to other cases in my modular system. The case is made of steel and is quite hard to drill. Due to the depths of the modules I installed, this perspective became the front, because otherwise the deepest parts were hitting the power distribution strips.
Modules are held in place by standard mounting screws in up to nine locations with sliding captive nuts. They are OK, but not as nice as the fixed tapped holes in my SoundMachines case. Unused nuts will slide around, unless you care to remove the wood end pieces to get rid of any you don’t happen to use. I used eight and let the ninth just rattle around, in case I might need it sometime in the future.
The wood end pieces are a separate purchase. They each come with two wood screws and small holes that line up with holes in the metal case. I had to drill out the holes in the wood to 3/32 inch diameter to get the screws to set easily. Pity the user who tries to screw them in without enlarging the holes. They’ll never seat.