Hey folks, I know that versions of this question have been beat to death so pardon me. I am having trouble finding metric data and wondering if anyone could help me understand.
I have built amps with clean, tight AC heater wiring and not had too much of a problem. I also have some of the Pete Millett DC boards and I've done some basic DC regulators now.
My question is this: in terms of noise / db / however I should be looking at this, what is the actual noise difference between properly twisted AC and properly regulated DC on a tube filament?
Also: I am not concerned with filament life, electron migration, etc etc. I'm specifically looking for information about lowering my noise floor.
I have built amps with clean, tight AC heater wiring and not had too much of a problem. I also have some of the Pete Millett DC boards and I've done some basic DC regulators now.
My question is this: in terms of noise / db / however I should be looking at this, what is the actual noise difference between properly twisted AC and properly regulated DC on a tube filament?
Also: I am not concerned with filament life, electron migration, etc etc. I'm specifically looking for information about lowering my noise floor.
asilker,
On what tube?
Indirectly heated tube, with a real cathode?
Direct Heated Triode?
On a 6.3V KT66?
On a 2.5V DHT?
On a 7V DHT?
On a 10V DHT?
Which type of DHT?
Even two 2A3 tubes on AC filaments will not have the same hum level after the hum pot is adjusted for each tube.
An indirectly heated triode concertina will have lots of hum if the tubes filament to cathode is leaky (that same 'faulty' tube works very well in a self biased stage that has a self bias resistor and bypass cap).
On what tube?
Indirectly heated tube, with a real cathode?
Direct Heated Triode?
On a 6.3V KT66?
On a 2.5V DHT?
On a 7V DHT?
On a 10V DHT?
Which type of DHT?
Even two 2A3 tubes on AC filaments will not have the same hum level after the hum pot is adjusted for each tube.
An indirectly heated triode concertina will have lots of hum if the tubes filament to cathode is leaky (that same 'faulty' tube works very well in a self biased stage that has a self bias resistor and bypass cap).
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