Hi all, I have finished my aion stratus, and it is distorting and passing signal and all controls are working as expected. Problem is there is no difference in sound between diodes installed and diodes removed altogether. So I guess I'm hearing opamp distortion only. Can someone who has built one have a look at my diode section and let me know if I've jumpered/ orientated properly?
Thanks!
It doesn't appear you have a switch in the SW1 location. You'll need an ON-OFF-ON or ON-ON mini-toggle to select between the two sets of clipping diode arrangements (or none at all in the OFF position). With no switch, it's behaving as if it's in the OFF position and none of the clipping diodes are in use. You are, as you guessed, only hearing op-amp clipping. If you only ever want to use one set of clipping diodes, you can solder a jumper between the middle and one of outside pads of SW1 to permanently select that (and only that) set of diodes.
Further, it appears you only have jumpers in the bottom set of diode groups. This will cause the first stage to be clamped at a gain of 1 and make the drive pot ineffective. I would expect the pedal to be clean and quiet when this position is selected.
Awesome, thanks for the detailed reply. Much appreciated!