There were a few questions about my Spring Reverb Driver so I decided to create a public thread to have it all in one place.
It is a pretty simple module in Kosmo format which is capable of driving reverb tanks from 8ohms to 600ohms input impedance. It has a dry-wet and a resonance control. PCB and panel are the same so components stick out.
You need to adjust some resistor values according to your reverb tanks input impedance. The input coil must not be grounded to the tanks casing in order to make it work.
I am not sure if I understand the “input not grounded” part. I have a BELTON B SN2EB2E/T tank and I checkd this document. So, I translated the code to
small, new, 2 springs, input impedance 600ohm, output impedance 2250ohm, medium decay, no outer channel, with tray.
I got back to this! With a little more thinking (wasn’t hard at all, I was just slow as usual) I knew how to bend the transistors and now it works (they need to be upside down, but then the middle and right leg switched!)! sounds pretty nice! The feedback comes in very suddenly, even though I used a log pot, but maybe that is just how it is. Thanks @jkb again!