Building 4 x reg's HT PSU's?

[Dave the bass]

Right, now then, having lived with that 300B amp at Owston and tweaking the driver I'm leaning towards making it the 'main' amp in the system for the downstairs system because I like the sounds it makes ... BUT... there's always a but... it currently requires 4 x external bench PSU's to run it, I'm thinking I could do better, so....

I want to replicate what I'm producing at the moment with those 4 x external supplies which is 4 independent regulated rails which are 2 x 150V @ ~ 35mA each for the 6C45P stages and 2 x rails 360V @ ~75mA each for the 300B stages. I'd like to put all the PSU stages into one 'box'.

Where to start from scratch building a dedicated PSU for the amp? Would 'the panel' advise Series Pass or Shunt Reg for which stages? Also, SS regulation and/or valve regulation... SS or valve rectification? etc etc... I've got a handful of TX's I can play with, I was thinking of a hefty double secondary 0-360 0-360 Toroidal TX I've got knocking about for the 2 x 300B stages and possibly 2 x 0-150V TX's I've got knocking about for the lower current 6C45 stages or a couple of 0-250V TX's perhaps.

I think the PSU will be way more bigger and complex than the amp!

DTB

[pre65]

I think the PSU will be way more bigger and complex than the amp!

DTB

As it's for use as the main amp, a man (boy ? ) with your woodworking skills could turn it into a smart piece of lounge furniture.

[Cressy Snr]

As it's for use as the main amp, a man (boy ? ) with your woodworking skills could turn it into a smart piece of lounge furniture.

Hey Phil, you're now irrevocably under female influence
Lounge furniture ?
I love it

[Nick]

Well, back to the original question. I guess you are happy with the solid state ones you have, so that would be a place to start.

Andrew does a lot of HT supplies I think based on the original Madia paper. But I noticed the other day, someone has updated it.

http://www.diyaudio.com/forums/tubes-va ... lator.html

Myself, I would think of a couple of 6080 series regs, but Mark has had very very good results with that T-Rex design. There is a long thread about it on here.

[izzy wizzy]

Not quite the answer to the question you is asking ....

I'd stay away from regs. Rather use separate supplies for outputs and driver. LC for finals, LCLC for driver. Well summit like that. Mayhaps LCLC for finals.

A reg is just another amplifier with its own signature so the supply is tainted with that. No reg is invisible IME.

IMHO, a passive supply, while heavier, probably more expensive and bulkier shouldn't give off as much heat and I would wager, sound better ... well to my ears.

cheers,

Stephen

[Andrew]

I like the Maida style regs, I shall have to look at that thread you ref'd Nick.

[simon]

That's a fine amp of yours Dave, I'm not surprised you want to box it up .

I thought Mark's amp with the T Rex style shunt reg was really nice, and that's the way I intend to go with Madness eventually, with three separate regs per channel for each of the 3 stages. And then I shall call it Insanity!

My only real experience with regs was when I added a shunt to the buffer in the DAC. It made a very big difference, literally transformed it. All I used was a simple shunt with half a 5687 sat on top of a 0A2 by following Steve's tutorial elsewhere here. The signal goes through the 0A2 which I've read isn't ideal, but it's simple and sounds good to me. I haven't tried it in a voltage amplifier though, but do intend to use this style for the 26 and 10Y.

How much current does the driver swing Dave? This is the limitation of this form of shunt reg, but this shouldn't be a problem for you. You could even use a simple 0A2 as you want 150V for the driver? Might be interesting to try.

The 300Bs are a bit more of a challenge, or the current requirement is at least, for a shunt. The T Rex seems to be a good way to go and puts the shunt in parallel with the cap to achieve the required current. Go for it Dave!

[steve s]

Not quite the answer to the question you is asking ....

I'd stay away from regs. Rather use separate supplies for outputs and driver. LC for finals, LCLC for driver. Well summit like that. Mayhaps LCLC for finals.

A reg is just another amplifier with its own signature so the supply is tainted with that. No reg is invisible IME.

IMHO, a passive supply, while heavier, probably more expensive and bulkier shouldn't give off as much heat and I would wager, sound better ... well to my ears.

cheers,

Stephen

My view .. At this point.. is that is a fair comment. i'm in the process of building twin split power supplies for driver and output, with a lot of chokes in it, the penny dropped a few weeks ago, I'm sure its about decoupling the power supplies from each other, but it not so much about the power supply...i don't think that matters too much as long as its a reasonable standard? Ie can hold the voltage without droop.
I think its about about the signals imprint on that supply once you start to play music, and with all the valves playing something different and being effected by all the other valves voltage , But only when they play .. Dave 's amp was a big event in my life ...
it showed me the decoupling cap in the power supply doesn't do what you are told it does. Or maybe its deemed good enough?.. I now think there are a few ways to clean the sound up,

[Dave the bass]

So many options open to me, thanks everyone for the seed-thoughts, s'preciated.

As appealing as an off-the-shelf-reg-kit is I'm tempted to have a bash at DIY-ing a solution 1st. If it doesn't work out I can always take one of the other routes.

I'll rub my hairy chin and report back.

DTB

[Nick]

IMHO,

it showed me the decoupling cap in the power supply doesn't do what you are told it does

It does exactly what we are told it does, but we often misunderstand what we are told.

[steve s]

So many options open to me, thanks everyone for the seed-thoughts, s'preciated.

As appealing as an off-the-shelf-reg-kit is I'm tempted to have a bash at DIY-ing a solution 1st. If it doesn't work out I can always take one of the other routes.

I'll rub my hairy chin and report back.

DTB

I've been doing that since i heard your amp with those power supplies
And still rubbing to be honest.. I built some new power supplies but i still to test them

[steve s]

IMHO,

it showed me the decoupling cap in the power supply doesn't do what you are told it does

It does exactly what we are told it does, but we often misunderstand what we are told.

Thats a fair point Nick...

[simon]

I think our Will's been using separate power supplies for some time, at least after the rectifier? Will?

Separate power supplies per stage makes a lot of sense to me, just not from a practical perspective.

[Cressy Snr]

Aye... separate power supplies for driver and power stage is the way to go, I've found.
In my pp amplifier, the twin power supplies are branched off the same transformer winding/SS bridge rectifier, so are not totally separate, but I use a valve damper diode, placed directly at the driver stage take off, to provide a one way valve, in case the power stage decides to drain the driver stage caps by trying to suck the juice backwards towards itself, via the junction.

This scenario is unlikely, since the power stage has a rather large reservoir, but nevertheless, the addition of the valve diode to guard the junction, greatly reduces interaction between the two halves of the amp.

A solid state diode would do the same job, but there would be no soft start for the driver stage.

[Will]

Yes separate supplies for each stage.. 23 chokes inc anode.