dmp
Well-known member
I've been planning to build a two channel tube preamp with UTC transformers and an RCA / Gates type circuit for some time. I built a RCA BA2 that I really like.
The coil audio version of the SA-70 has an output control ( between the tubes, so replaces R5) and a feedback (a pot in line with R8 I suppose), which is a cool feature.. In the demo I heard, the feedback doesn't seem to change the volume - just the tone. I don't understand how that would be accomplished? But they claim 42db-54db of gain so maybe that is the feedback sweep?
Ideally I'd like to build something that could go up to 60 db of gain. Suggestions?
The coil audio version of the SA-70 has an output control ( between the tubes, so replaces R5) and a feedback (a pot in line with R8 I suppose), which is a cool feature.. In the demo I heard, the feedback doesn't seem to change the volume - just the tone. I don't understand how that would be accomplished? But they claim 42db-54db of gain so maybe that is the feedback sweep?
Ideally I'd like to build something that could go up to 60 db of gain. Suggestions?