5v333
Well-known member
hi!
im playing around with feedback and compensation.
attached is an imaginary pic with three different tube setups. the first is just two triodes with global NF. plate resistor of first triode is 100K for lowest distortion.
the second uses some local feedback around the second triode.
the feeback improves thd of the second triode and seems to be able to compensate the amp or part of it without inserting extra caps.
to use as much feedback as possible without loading the first triode im thinking about using 200K on both the feedback resistor and the plate resistor. by doing so, i assume the first tube will keep its DC characteristics. right?
now i thought, can we have an even lower feedback resistor and still maintain the DC characteristisc within the first triode?
pic three shows that the plate resistor and feedback resistor has become one.
now taking its DC current through the OT while at the same time passing AC between the triodes for feedback within the same resistor.
would this work?
im playing around with feedback and compensation.
attached is an imaginary pic with three different tube setups. the first is just two triodes with global NF. plate resistor of first triode is 100K for lowest distortion.
the second uses some local feedback around the second triode.
the feeback improves thd of the second triode and seems to be able to compensate the amp or part of it without inserting extra caps.
to use as much feedback as possible without loading the first triode im thinking about using 200K on both the feedback resistor and the plate resistor. by doing so, i assume the first tube will keep its DC characteristics. right?
now i thought, can we have an even lower feedback resistor and still maintain the DC characteristisc within the first triode?
pic three shows that the plate resistor and feedback resistor has become one.
now taking its DC current through the OT while at the same time passing AC between the triodes for feedback within the same resistor.
would this work?