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To be honest I installed the bypass cap from the beginning and never looked back. Due to the CCS on the plate the bypass cap should not be doing anything to the sound except lowering the output impedance. I may experiment at a later date with switching it in and out.
The cap is 220uF I believe (maybe 100uF), forget the brand. Decent quality cap though, ~$1.
Here's my latest project being auditioned. I finished these two mono, balanced push-pull pentode amplifiers this afternoon.
At the moment,they are fitted with Electro-Harmonix 6CA7EH output tubes.
The amps use plate-to-grid feedback in the Schade tradition.
Input stage is a pair of NOS 6BS7 top-cap grid pentodes. These are equivalent to the once ubiquitous EF86 and use a spiral wound heater to reduce noise.
Driver tube dead centre, is a GE7044, configured as a pair of cathode followers.
Input stage screen grids are regulated by a simple cap-bypassed zener shunt.
Output stage screen grid regulation is courtesy of a 6SN7 configured as a shunt plus grounded grid error amp and is mounted between the two 6CA7EH. I found this circuit in Merlin Blencowe's book on power supplies and it performs really well. All iron comes via Danbury Electronics.
The amps are fed from a passive, silver-wired, balanced preamp using Sowter 3575 phase-splitting transformers and a Khozmo stepped attenuator.
This can be seen behind the right hand amplifier, on top of my Musical Fidelity M1 DAC.
Could be a long night
An externally hosted image should be here but it was not working when we last tested it.
At the moment,they are fitted with Electro-Harmonix 6CA7EH output tubes.
The amps use plate-to-grid feedback in the Schade tradition.
Input stage is a pair of NOS 6BS7 top-cap grid pentodes. These are equivalent to the once ubiquitous EF86 and use a spiral wound heater to reduce noise.
Driver tube dead centre, is a GE7044, configured as a pair of cathode followers.
Input stage screen grids are regulated by a simple cap-bypassed zener shunt.
Output stage screen grid regulation is courtesy of a 6SN7 configured as a shunt plus grounded grid error amp and is mounted between the two 6CA7EH. I found this circuit in Merlin Blencowe's book on power supplies and it performs really well. All iron comes via Danbury Electronics.
The amps are fed from a passive, silver-wired, balanced preamp using Sowter 3575 phase-splitting transformers and a Khozmo stepped attenuator.
This can be seen behind the right hand amplifier, on top of my Musical Fidelity M1 DAC.
Could be a long night
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Ask Azazello, he is the Chief Designer of the amp. ;-)
Yes, PS tubes with strong emission.
Guess its not so far fetched to figure out. Is it an LTP and what PP primary load is it using?
I like your tube arrangement. Like a little gathering around the campfire, except they are the campfire.
Azazallo (Nikola) arranged by a 6-point star after a Jewish picnic. ;-)
