Power supply layout - is it critical?

[nickt]

Ken built great sounding amps - no argument - but is the power supply layout anything to do with the sound?
I can understand the preamp layout being critical but the PS?

Volts is volts, right? or not?

Any opinions greatly appreciated before I start my express

Thanks!

[skyboltone]

I used the Francesca layout on my first one but I'm gonna experiment with an all board mounted setup on the next.

[Phil_S]

Short answer: No.
This isn't the neatest work. If I did it again, I'd work it out with a bit more room to make it tidy. It is every bit as functional as it should be. This build is for two 6AQ5 power tubes and uses a lower voltage PT. That is the reason the first dropping R in the power supply ladder is 9k1 instead of 18k2. Otherwise, this is pretty faithful to the design. This worked out to supply the pre-amp stages with appropriate Express voltages.

[Ed de Jager]

Pardon me for saying but i think yoù forgot to solder the filter cap and resistor nearest to the switches.Or does it just look that way?

[Phil_S]

I see it's not obvious to all that these pictures were taken when the amp was not yet complete. Take a good look at the tube sockets.....
Regards,
Phil

[Ed de Jager]

I knew i was saying something stupid when i was typing.Just didn`t know what it was.Thanks for pointing it out.

[Phil_S]

Ed, we should just move on...things happen, people say stuff. I wasn't looking to make something of it.

I'm actually surprised that no one has criticized my approach. It just treated this only like every other build I've done. I shoehorned in the power supply where I could based where other things fell. The board is a generic board from Ted Weber and I think he sells them for under $10. I had some fun with the layout. It's not perfect. There are things I would change if I did this again. Anyhow, it seems to have worked out, and there is no hum in this amp, which would be a big concern with the power supply. It's my understanding that power supply layout shouldn't have much, if anything, to do with tone, which is shaped primarily in the preamp circuit.

[nickt]

Hi Phil,

between your success and the Komet layout I'm pretty convinced the TW PS can be rearranged without any "magic mojo" leaking out.

BTW how close to the original did your preamp end up being?

Thanks!

[Phil_S]

The preamp is really close. Supply from B+1 to B+5 is: 333, 327, 297, 287, 278. These were *so good* I decided it should be left alone. The PT HT winding is feeding about 262vac to the rectifier.

[My-Co]

Not magic, But it's physics. In phase or out of phase. Noise ratio's. Just think about it. You may be on to something.
Thank you
Mico

[El_Martin]

Hi there!

How do you define critical? I found some differences in my off-the-beaten-track layout (TeleWreck 15 W). Even with some variations of the power supply.

From different types of rectifier diodes (1N4007s or UF4007s) everything made some differences. Most of them were minor. Greatest single failure source would be the grounding scheme imho.

I would not expect an Express to be different from my Liverpool variant.

As long as you keep the rectifiers and first filter cap close to the PT, use an approved grounding scheme and keep all other PS wires short, youre on a winning street...
OK, would not recommend to put the PS too close to V1

Ciao
Martin (proud owner of two (yes!) homegrown TW inspired amps)

[mhuss]

In my experience (and based on input from Paul Ruby), the most important thing is to minimize the B+ secondary lead length, tightly twist the wires, and connect them right at the rectifiers and 1st filter cap. The other most important thing (tied for first ) is good grounding practice.

--mark

[jlatrace]

Mark,
Help me undertsand your recommendation concerning B+ secondary wires. I have used a marshall style layout and am having a little more hum than I'd like when the amp is cranked from 2 oclock and up.
Les