Has anyone experimented with Self’s original or updated line in? Fig C is in Small Signal Audio Design and dates back quite a ways, while Fig D is applied to a Balance control in the updated hifi preamp design from Linear Audio a few years back.
I’ve run a zillion numbers based on these and it’s a stretch to create a +/-10dB line trim. +/-6dB is easy. Significant gain is within reason, still low noise up to about +20dB if your input impedance is a conservative 2K. Just curious about real world implementations, and how people like the gain curve. The main challenge for me is getting 0dB to sit at center of travel — I can’t quite grok that calc.