Pro Audio Design Forum

One thing that occured to me while I was writing my initial post is that in case I use something like your differential Deboo integrator as servo (which has a common-mode gain of 1x) the whole servo would be "riding" on CM signals when monitoring the emitters and injecting into the bases....

So I understand correctly where you're headed with this what is the value range of C1 and C2 you propose? 2u2 film caps. I don't see a servo in your schematic forwards or backwards. Don't worry, your eyes are doing just fine, it's my schematic which is not showing a servo. I didn't draw the servo b...

If I understand correctly it seems to me that if you're sampling the emitters to measure the offset and then modulating the emitter current to provide correction that your sample and control points are effectively the same. Yeah, it looks like that. Especially once one draws a schematic it looks &q...

I'm working on a slightly different DC-servo for a mic-pre using the typical instrumentation amp topology. Repeated online searches brought me here over and over again, so I decided to present my idea here. PART 1 Below is the (simplified) "classic" input stage as basis for the discussion:...