[sdiy] Moog reverb tanks and impedances

[David Ingebretsen]

My fascination is turning to spring reverbs. I've had a look into the subject, and am unsurprisingly overwhelmed. So many ways to process and drive a set of reverb springs. Tube, discrete, OpAmps, amazing for such a simple device.

That said, I had a look at the Moog 905 circuit, very simple, but still I found at least one error. Even I could see it! Did Moog publish even one schematic that was error free? I digress...

Does anyone know the specs on the tanks used in the Moog reverb? Input and output impedances? I take from the schematic the input should be grounded and the output insulated.

I've simulated the circuit and measured the theoretical impedances at 1 kHz, and I will probably do the math, too. I'm just curious what Moog used as a sanity check.

David