New Paul Hynes SR5 Power Supply

[chris@panteg]

Why ' what's wrong with your HE psu ?

[Marco]

The HE should be pretty good, although of course I haven't done a direct comparison between the two....

Andrew, if you're curious, we could swap PSUs for a week - that way we'll both be able to assess which one we think is best, and if the SR5 isn't as good as the HE (which I doubt), you won't have wasted any money

Marco.

[DSJR]

I'm genuinely surprised there's such a difference in these supplies, unless it's the noise behaviour getting back into the cartridge in some way, or possibly the very "fast" quartz servos or summat

That PH supply has a hige transformer in it that I reckon would do a mid priced integrated amp good service

[Marco]

Indeed - and that's precisely what's lacking in the HE

Experience tells me that hugely 'over-specced' T/T PSUs, using massive mains transformers (for the job), often sonically outperform other PSUs which don't use such large mains transformers - why, I'm not sure, as I believe technically it *shouldn't* make a difference once one achieves 'the ideal' in an electrical sense.

However, I'm sure that Paul could provide a credible technical argument for why having such a huge mains transformer inside a T/T PSU is sonically beneficial. Lower noise, perhaps? Paul, what's you're take on it?

The theory that suggests it shouldn't make any difference was blown out the water, however, around 2004 when I swapped the (then) Linn Lingo on my LP12 for a Norton Airpower, which used a massive mains transformer, similar to the one Paul has in the SR5, and the improvement the Airpower brought over the Lingo (and an Armageddon I tried at the same time) wasn't subtle!!

I don't believe that there was anything particularly 'fancy', component-wise, inside the Norton - its design principles were mainly based around its huge mains transformer.

It's yet another example where measurements alone (at lease those normally used in these applications) don't always tell the full story.....

Marco.

[Ammonite Audio]

Marco, if you recall, I once walked into a spat with Dave Cawley over aspects of PSU design that I don't fully understand, but which Paul Hynes does! He does explain the principles on his website. Clearly a big toroid helps, but fundamental design helps even more!

My feeling about the Technics and why it responds so well to PSU magic, is that it probably presents a rather complex load, which translates into the need for a very fast and very wide bandwidth PSU. Clearly some PSU designs are better than others

[DSJR]

Maybe we're not looking finely enough at instant temporal responses to needed current (I can't explain it properly but hope you get the idea).

One thing Naim really did do was to re-introduce the over-supply idea, especially on their preamps. I know this is only a tiny part of the picture, but having a high capacity reservoir in both transformer and storage caps may count more than otherwise thought - I wish I'd been better at advanced maths, as I could have been an electronics engineer and able to work it all out. PLEASE Mr Hynes, help me out here.....

[Reid Malenfant]

This might help explain things or might raise more questions

All an amplifier is basically boils down to it being a power supply that supplies AC voltage to a load. Now those that have experienced class A amplification tend to want to stick with it, this is because all the current that the load will ever require is already there at the output stage. It never needs to turn on any harder unless it goes into class B with some ridiculous load. This should make the amplifier pretty fast & low distortion...

What you have with the SR5 is basically a class A power supply It's shunt rather than series regulated & this means that all the power that the turntable doesn't use is being dissipated by the shunt transistor or mosfet (probably a lateral mosfet from what i have been reading). To increase the load currennt the shunt mosfet actually needs to turn off some rather than on. Again it can react very fast indeed just like a class A amp & it should have a much lower output impedance as a consequence

A series regulator is like a class B amp in that it needs to turn on harder to supply more current & this takes time so it's slower, though more efficient.


The reason the transformer is large is due to the class A type of operation where all the power would need to be dissipated by the PSU itself with no load connected. As well it being sensible to use a big transformer for best performance.

You want a car to go fast & accelerate like the clappers then fit a dirty great big V10 engine. If you are happy to chug along, accelerate slowly & slow down going up a hill (when the going gets tough) then fit a 1L four cylinder jobby

18:48 E2A:- Just been looking at the pictures of the interior of the SR5 I might be mistaken but it looks like a series regulator to me, i can't see a dirty great big aluminium clad wirewound resistor that would be needed as a series component to dissipate power Besides that there is no where near enough heatsinking for a shunt regulator

[chris@panteg]

Indeed - and that's precisely what's lacking in the HE

Experience tells me that hugely 'over-specced' T/T PSUs, using massive mains transformers (for the job), often sonically outperform other PSUs which don't use such large mains transformers - why, I'm not sure, as I believe technically it *shouldn't* make a difference once one achieves 'the ideal' in an electrical sense.

However, I'm sure that Paul could provide a credible technical argument for why having such a huge mains transformer inside a T/T PSU is sonically beneficial. Lower noise, perhaps? Paul, what's you're take on it?

The theory that suggests it shouldn't make any difference was blown out the water, however, around 2004 when I swapped the (then) Linn Lingo on my LP12 for a Norton Airpower, which used a massive mains transformer, similar to the one Paul has in the SR5, and the improvement the Airpower brought over the Lingo (and an Armageddon I tried at the same time) wasn't subtle!!

I don't believe that there was anything particularly 'fancy', component-wise, inside the Norton - its design principles were mainly based around its huge mains transformer.

It's yet another example where measurements alone (at lease those normally used in these applications) don't always tell the full story.....

Marco.

Hi Marco

Back in the day when i had an LP12 ! i just got the Lingo , but then i noticed all these other psu's available ' i talked to my Linn dealer and this is what he said ' please ' please don't go near any of these dogdy ' possibly illegal aftermarket rubbish psu's they will ruin your LP12 , err yeah ok .

I think this kind thing still go's on but is one of the reason's i moved the LP12 on , but not the main reason of course .

[Wakefield Turntables]

The HE should be pretty good, although of course I haven't done a direct comparison between the two....

Andrew, if you're curious, we could swap PSUs for a week - that way we'll both be able to assess which one we think is best, and if the SR5 isn't as good as the HE (which I doubt), you won't have wasted any money

Marco.

Marco,

Now that seems like an offer too good to refuse Let's wait till after Xmas, I need to fine tune the Mike New bearing/stiffning plate/Cu composite platter and SME V before I let the Timestep go. I've only just got the whole thing set up and working so I want to listen to some vinyl before I embark on another batch of upgrades. How does back end of January sound??

[MartinT]

I need to fine tune the Mike New bearing/stiffning plate/Cu composite platter and SME V before I let the Timestep go.

Andrew, how did you find the base plate installation? I wrote it up elsewhere, not sure if you saw that.