I did build 2E22 SE amp with AC filament (because I like AC for filament ). Sound is so sweet and warm. Hum is > 13mVac, so I can hear them at my chair.
I intend to take an ultrapath with a Capacitor between power tube's cathode to B+ in oder to get lower hum AC and lower gain. There are some ultrapath schemas on the internet, but the tube is auto bias. Mine is fixed bias .
So :
- How can I calculate the value of this capacitor ?
- 2 these capacitors will be connected to the same point, B+. Is it OK ?
Thanks and regards,
QA.
I intend to take an ultrapath with a Capacitor between power tube's cathode to B+ in oder to get lower hum AC and lower gain. There are some ultrapath schemas on the internet, but the tube is auto bias. Mine is fixed bias .
So :
- How can I calculate the value of this capacitor ?
- 2 these capacitors will be connected to the same point, B+. Is it OK ?
Thanks and regards,
QA.
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Hi,
Have you tried winding a filament transformer with bifilar wound
3.15V windings, connect them in series and use them to power the
filament? Sensing resistor is soldered to the junction of the two windings.
I once did this with my 3C24 and there was no audible hum a foot
from my 12" fullranger.
As always, YMMV.
Reza
Have you tried winding a filament transformer with bifilar wound
3.15V windings, connect them in series and use them to power the
filament? Sensing resistor is soldered to the junction of the two windings.
I once did this with my 3C24 and there was no audible hum a foot
from my 12" fullranger.
As always, YMMV.
Reza
Hi,
Have you tried winding a filament transformer with bifilar wound
3.15V windings, connect them in series and use them to power the
filament? Sensing resistor is soldered to the junction of the two windings.
I once did this with my 3C24 and there was no audible hum a foot
from my 12" fullranger.
As always, YMMV.
Reza
I use separate toroided transformer for 2E22 filament, so hum get a bit low. I will try CT transformer.
There are some ways of hum cancelation for DHT. I never try this way : http://www.dmitrynizh.com/dht-filament-hum-cancel.htm
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