mylesgm said:
I've a lead on a few schoeps mics that use P12 phantom which is not T-Power but I can find very little to no info on this and there don't seem to be any commercially available converters for powering these mics from a P48 supply Any ideas or leads?
The difference between P12 and P48 is the former uses 680r resistors instead of 6.8k, with an open-circuit voltage of 12Vdc instead of 48. The max current is 15mA for P12 vs. 10mA for P48.
Typically, a P12 mic draws more current than its P48 counterpart; the result is that many P12 mics will operate correctly under P48 (the contrary is not true).That's probably the reason why nobody makes adapters...
Can you get some more info about these mics, particularly their current draw? Then it would be easy to evaluate the voltage drop. In case the voltage drop is not enough, resulting in excessive supply voltage to the head amp, there is a risk of damaging components, in particular capacitors that may not be sufficiently rated.
Now, if you look at the Schoeps schemo, and these mics are somewhat related to the CMC5 type, you may see that all versions are quite similar, except for one resistor (R10); instructions are printed on the schemo.
The capacitor is rated 40V, which makes operation with P48 safe, because the current draw is about 9mA, so the voltage drop is 9x3.4, or about 30V, resulting in about 18V at the transistors' emitters.
while there are heaps of P48 to T-Power supplies.
Really? I'd be curious...