Adding Output Transformer to existing circuit

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Winston OBoogie

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I didn't know the reference either but 'Morganfield' works for me. Or is it Morgan Field, or simply "Morgans"?
 

kimothebeatmaker

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Do you agree with the fact there is no DC current into RV11, because there is capacitor C79 in series? As a result it has no effect on the FET bias.

Agreed. It could be argued that it sets the FET's current, though.



I still claim that RV11 is a treble bleed, and I said in my first post that it's a crude source of distortion. And RV12, as a bias control, also changes the operating point of the FET, which in turn changes the distortion profile.

Correct, I had misread that for RV10.



No. You can say that as much as you wish, but it's simply not true.
You asked what was the purpose of said component was, and I am telling you what it is. The RV10 is not for saturation…RV11 is. But back to the topic at hand, if we can please stay on topic that would be helpful.
A 1:1 transformer on the output, primary/secondary from the capacitor spots on the output like in the picture I posted, would this work?
 

abbey road d enfer

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Did you figure this out yet? I couldn't find C31/29 I would say the best way to keep the theme of the unit and ease would be to find the highest output current opamp you can and put it on your points and put a 1M or less resistor across it maybe with a coupling capacitor and 51/56 ohm resistor in series to the opamp input, and try to drive the transformer with it as a buffer - you might have to add 56 ohms on your output of the opamp as well to keep the impedance high enough.
This is a rather contradictory suggestion, since you propose at the same time avoidig distortion by not loading the existing circuit and adding a resistor in the primary of the transformer, which increases ditortion.
but was wandering how simple would it be to just do something similar to my unit. In the picture, he removed the electro alum caps on the output, ran the prim / sec leads to those in palce." This is a good idea if you have a similar situation in the schematic why not?
This has already been considered. It's bound to increase the distortion figures, but may increase the Morg measurement.
 

kimothebeatmaker

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edit2: "What got me thinking about adding a transformer inplace of the capacitors on the output was this picture of the chameleon labs 7720 modified with a jensen 123 output transformer. I know it's a compressor and a different beast, but was wandering how simple would it be to just do something similar to my unit. In the picture, he removed the electro alum caps on the output, ran the prim / sec leads to those in palce." This is a good idea if you have a similar situation in the schematic why not?
Similar but not identical. I would be taking the outputs of the OPA1604 A and D, into the primary of the Jensen 123-S, and the secondary to to the XLR pins. Thoughts?
 

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