HT High Current Voltage Regulator

[deltavektor]

Hello

I have searched the internet and this great site with no satisfying results. I am in need of some guidance to construct a high voltage, high current voltage regulator for a single-ended power amplifier. I just cant get my amplifier quiet using a CLC network and now would like to resort to propper modern technology

I believe Wavac uses serious regulators in their power amplifiers and that is one of the reasons why they are highly regarded as the best SE amplifiers on the market. I have had experiences on pre-amplifiers that was so noisy one could not use them but as soon as a regulator was installed they transformed from vintage clunkers to serious audio instruments.

At the moment I guess I need a regulator per channel with the following specs

Power stage (single 6C33C tube):
1.5 ampere
215 volt direct current

Driver stage (casoded 6H30Pi):
200mA
410 volt direct current

Bias network:
800mA
255 volt direct current

MOSFet is the choice of semiconductor thus reducing size. Chokes are just too clunky.

Thanx for popping by

[deltavektor]

Any hints.

I came across the Maida regulator scheme and think it could work for my application.

[Williams Audio]

hi,
even when using an active regulator at SE amps you will need a kind of CLC or LC smoothing filter.
take a look at old books from National semiconductors and Motorola application notes referring regulators, these will guide a bit in the correct direction.
best regards
Williams

[Williams Audio]

hi,
second important thing is think simple.
i suggest you to regulate ( low current ) the voltage supply for voltage amp and driver stages and, I think TI has an IC that will do, it can handle 250V and about 500mAmps; apply a good LCL, LC filter for the SE output stage,
it will be good enough.
by the way this is the topology used by most amp designers, if is working for them then it will work for you too.
Best regards
Williams

[janneman]

Originally posted by deltavektor
Hello

I have searched the internet and this great site with no satisfying results. I am in need of some guidance to construct a high voltage, high current voltage regulator for a single-ended power amplifier. I just cant get my amplifier quiet using a CLC network and now would like to resort to propper modern technology

I believe Wavac uses serious regulators in their power amplifiers and that is one of the reasons why they are highly regarded as the best SE amplifiers on the market. I have had experiences on pre-amplifiers that was so noisy one could not use them but as soon as a regulator was installed they transformed from vintage clunkers to serious audio instruments.

At the moment I guess I need a regulator per channel with the following specs

Power stage (single 6C33C tube):
1.5 ampere
215 volt direct current

Driver stage (casoded 6H30Pi):
200mA
410 volt direct current

Bias network:
800mA
255 volt direct current

MOSFet is the choice of semiconductor thus reducing size. Chokes are just too clunky.

Thanx for popping by

Bias current 800mA? 160W of bias power, more than all of the amp? Is that true??

Jan Didden

[AKSA]

Yes, agree emphatically, 160W of bias current? WOW!!

You can do a nice shunt regulator with a tube using grounded grid and a TL431 regulator in the cathode circuit. See John Broskies' site for this approach, saves on heatsinks.....

Hugh

[unclejed613]

you could also do the "tube" thing and use gas regulators. they operate exactly like zeners, only at much higher voltages. you could use gas tubes (or a string of neon bulbs) as a reference for a transistor regulator.

[Gordy]

The Maida type should be able to be configured for your driver stage. Search this forum for 'Maida' for interesting threads.

You may be able to rig high-current by-pass transistors with a Maida type for your main amp. I've not done it but believe that it is possible.

Your bias calculation needs recalculating!


The guys in the Tube section of the forum have lots of experience of this type of thing.

: )

[deltavektor]

Originally posted by AKSA
Yes, agree emphatically, 160W of bias current? WOW!!

You can do a nice shunt regulator with a tube using grounded grid and a TL431 regulator in the cathode circuit. See John Broskies' site for this approach, saves on heatsinks.....

Hugh

This is PSU spec and not the circuits actual current draw.

Overkill never hurt anybody, right?

Okay - I'll then do a regulator + CLC. I do have most of the goods already.

At the moment the amplifier sounds like a vintage Fender amp on standby. Bzzzzzzzz....

[gabdx]

I am planning to build an amplifier exactly like yours and can't find a good regulator either ,

The max power of the regulator could be twice the bias ma ,just more realistic than 1.5 A...