Hi,
Wondering if anyone is familiar with this type of circuit.
L+R plus L-R
SE grid drive with 20mA 2k type, transformer coupled to push-pull output stage loaded with two series fed and air gapped output transformers per channel, twin low impedance secondaries to facilitate the operation.
I have a circuit and some notes and wish to explore extending this to using the subtracting signal to send the error/distortion (will be the difference between respective tubes in the output pair output circuit) back to cathode of the driver - it shouldn't affect voltage gain and plates should still be tightly coupled (without the DC issues inherent to PP transformer) and without feedback to the actual (passed through) signal. Most importantly, I see a possible reduction of some 6-8dB in both 2H and 3H products, in proportion and also some balancing of any gain mismatch between the output tubes
Alternatively, shorting out the subtracting signal to remove 2H and 3H in the proportion to which they exist within the output pair.
If anyone knows a bit more about hybrid/bridging mixer circuits and the use of subtraction - please send me a PM - I think it should work but need a work-through before springing for custom OPT x4.
Sincerely,
LH/S
Wondering if anyone is familiar with this type of circuit.
L+R plus L-R
SE grid drive with 20mA 2k type, transformer coupled to push-pull output stage loaded with two series fed and air gapped output transformers per channel, twin low impedance secondaries to facilitate the operation.
I have a circuit and some notes and wish to explore extending this to using the subtracting signal to send the error/distortion (will be the difference between respective tubes in the output pair output circuit) back to cathode of the driver - it shouldn't affect voltage gain and plates should still be tightly coupled (without the DC issues inherent to PP transformer) and without feedback to the actual (passed through) signal. Most importantly, I see a possible reduction of some 6-8dB in both 2H and 3H products, in proportion and also some balancing of any gain mismatch between the output tubes
Alternatively, shorting out the subtracting signal to remove 2H and 3H in the proportion to which they exist within the output pair.
If anyone knows a bit more about hybrid/bridging mixer circuits and the use of subtraction - please send me a PM - I think it should work but need a work-through before springing for custom OPT x4.
Sincerely,
LH/S
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