• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

300b with single stage driver, C3M or?

daanve,

With a regulated power supply you have another amplifier in the signal chain....
SE is class A by definition, so IMO a regulated power supply should not be necessary.
When used to overcome LC input filter supply problems you're on the wrong track.
When power supply transformer and choke are made for the application, LC input supplies work well (at least in my experience...).

Of course.
It is a common, almost inextricable misconception that accuracy gives low distortion, actually, the cure is worse than the disease. Transients have the ability to travel through galvanic isolations and don`t allow themselves to be shunted, certainly not by shitty IC voltage regulators.
 
LC and CLC filters both work well when designed properly; it's a design choice.
With a small value input capacitor it will work like something "in between".
Advantage might be the option to tune the output DC voltage.
In the meantime we're getting OT, turning the thread into a LC/CLC power supply discussion...
 
Massive iron is what you like, isn't it?
Sakuma-san used even two chokes in his (CLCLC) HV supplies...
My SEP amp uses CLCLC PSU, too. Sounds superb. Even with a cheap tube like F2A. Just want my amps to sound real, without any artefacts of tube sound.
Interesting enough, thats possible, even with cheap tubes. It mostly depends on the perfection of circuits, build quality and parts.
 
Last edited:
filament psu
 

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Take care Andy, you're opening a can of worms...
But OK, to give you a nice starter, here is my take of what IMVHO is the most important in a (SE) tube amplifier:
1. power supply (after all, an amplifier modulates the power supply into AF so there you are);
2. circuit design;
3. transformers;
4. choice of tubes.
So yes, choice of tubes comes last!
 
Take care Andy, you're opening a can of worms...
But OK, to give you a nice starter, here is my take of what IMVHO is the most important in a (SE) tube amplifier:
1. power supply (after all, an amplifier modulates the power supply into AF so there you are);
2. circuit design;
3. transformers;
4. choice of tubes.
So yes, choice of tubes comes last!

I almost agree - again.
An amplifier only attenuates power.
 
My power supplies are all small cap > 10H choke > 100uF - > R > 10uF. All the caps are motor run polypropylene. Rod doesn't think much of them!! Rectifier is AZ1/AZ11 mesh pair in parallel.

I don't have a "preamp" or active plate load. I just have a 2 stage amp where the driver is loaded with a plate choke and followed by .2uF FT-2 caps. My AK4490 DAC goes straight into the amp. I've pretty much decided on 300b finals but have a pair of F2A to try and also a pair of 2a3. I've eventually found a small number of drivers I like the sound of, but they're very rare and I have a real job finding them.
 
My power supplies are all small cap > 10H choke > 100uF - > R > 10uF. All the caps are motor run polypropylene. Rod doesn't think much of them!! Rectifier is AZ1/AZ11 mesh pair in parallel.

I don't have a "preamp" or active plate load. I just have a 2 stage amp where the driver is loaded with a plate choke and followed by .2uF FT-2 caps. My AK4490 DAC goes straight into the amp. I've pretty much decided on 300b finals but have a pair of F2A to try and also a pair of 2a3. I've eventually found a small number of drivers I like the sound of, but they're very rare and I have a real job finding them.


I dont either, the motor runs unlike DC links arent optimized for low ESL most of the times. Wheras those modern blocks made for local decoupling in power inverters (IGBT) Capacitors need to provide good impedance from DC to several 100's of Khz.


AZ4/12 is the higher current version of the AZ1 there are versions of the AZ12 with black mesh, made by the Hun.


Cheers

V4LVE