Paul Hynes SR7EHD PSU - unlocking the latent potential of my Technics SL-1210 [Archive]

Marco

21-11-2011, 13:29

Guys,

Some of you may know that I've recently upgraded my T/T PSU from the Paul Hynes SR5-21 to the new, and hugely over-specified, SR7EHD. Therefore, here are my thoughts on what has been been achieved, sonically. First, a some pics of the beastie, in order to get the ball rolling:

Front:

http://img12.imageshack.us/img12/6640/img1106rv.jpg (http://imageshack.us/photo/my-images/12/img1106rv.jpg/)

Back:

http://imageshack.us/a/img405/8633/14d57a07.jpg (http://imageshack.us/photo/my-images/405/14d57a07.jpg/)

It also weighs a ton! :eek:

The 3-pin connection at the back is for Paul's Clearsilver XL lead, the claimed electrical benefits of which Paul will outline here shortly. I will have the lead in my possession soon, and will do a comparison between it and my silver DCSXL cable, fitted with Furutech CF-60 XLR plug, and FP-682F socket on the back of the PSU.

In order to fully maximise performance, the SR7EHD has also been fitted with a Furutech FI-10(R) Rhodium IEC inlet.

As the SR7EHD is slowly running in from new, I can hear exactly what it's doing with music - and what it's doing is quite astonishing..... Its huge reserves of current driving capability are allowing my T/T to deliver so far unrealised levels of musical analysis.

I suspect that this is due to further lowering the noise-floor delivered by the (already excellent) SR5-21, and simply giving the turntable's regulator and control circuitry an even easier ride, rather like I suppose fitting a bigger and better engine to a car, which has the inherent design capability to maximise the benefits of the increased 'horsepower', or slotting a better and more powerful amplifier into a system that is able to fully showcase its superior music resolving abilities.

Although such a huge power supply for the Technics is arguably WAY 'over the top', in terms of the measurable current it can draw (and some would therefore say unnecessary), listening tests clearly indicate that there are still significant sonic gains to be had by going down the over-specified transformer route. It is beyond question to my ears that, with the Technics SL-1200/1210, latent potential exists, waiting to be untapped, when the use of a judiciously over-specified external PSU is employed. Paul I'm sure will provide the technical rationale.

In short, with the introduction of the SR7EHD, my system, when playing vinyl, has subjectively more available 'headroom' in order to portray music with greater conviction. What this means, in real terms, is that timing is improved to the extent that rhythms are sync-locked to new levels of foot-tapping syncopation, and music is now underpinned with a security and authority, together with an overall effortlessness that I've never heard before from my modified SL-1210 (or indeed any T/T I've had experience of using), making for more believable and enjoyable listening to all genres of music.

Tunes are now driven along with an incredible (and indeed infectious) alacrity, seemingly unhindered by any recognised physical or technical restrictions of the vinyl reproduction chain, thus allowing rhythmic development within the musical structure full reign. This results in the unlocking of nuances in familiar recordings, which although present with the SR5 were, in comparison, somewhat 'held in check', resulting in their role in the musical picture being diminished and therefore less influential in allowing a faithful rendition of the music reproduced. Well, with the SR7EHD, that musical picture is now complete.

I can confidently say that the addition of the Paul Hynes SR7EHD has been a revelation, and no doubt it will become even more so, as the burning-in process continues towards its completion.

Anyway, enough typing, it's time to spin more tunes! :cool:

Marco.

freem

21-11-2011, 16:04

Groan! Anyone want to buy an SR5.

Marco

21-11-2011, 16:33

Wakefield Turntables

21-11-2011, 16:45

Marco,

Thanks for the description of your SR7EHD, I put my order in for the more exotic version of this and can honestly say that I cant wait. I think I ordered it about 2 weeks ago and every day seem like a week waiting for it :( In the meantime I do have a Audiotechnica SUT sitting in my system so when I get the next PSU from Paul I should be able to give you some idea of how mine works!

Andy

freem

21-11-2011, 17:12

Hi Paul,

The SR5 (and SR3) are still very valid products at their respective price points, and in my opinion, are streets ahead of the commercial competition, in terms of the sonic performance that they offer.

The SR7EHD simply raises the bar from excellent to sensational, and shows just what is possible when Paul *really* puts his mind to it! :)

Marco.

Hi Marco

I agree with you wholeheartedly. Having made the decision to take development of the Techie all the way, I regret that the SR5 isn't upgradeable and that if I want to move forward again will have to be sold on.

Paul.

MCRU

21-11-2011, 17:15

Hi Paul,

The SR5 (and SR3) are still very valid products at their respective price points, and in my opinion, are streets ahead of the commercial competition, in terms of the sonic performance that they offer.

The SR7EHD simply raises the bar from excellent to sensational, and shows just what is possible when Paul *really* puts his mind to it! :)

Marco.

But Dude you have not tried ALL the commercial compettion PSU's have you so cannot categorically state which is best surely? :)

Marco

21-11-2011, 17:23

Hi David,

Of the T/T PSUs I've heard *so far*, the SR7EHD is unquestionably the best, to my ears in my system. Obviously that opinion is only valid up until, or if indeed, I hear something better in the same context :)

Why not bring your own PSU, or any others you sell, to Dom's bake-off and see how it stacks up? I'd value your opinion on the matter :cool:

Marco.

Artifolk

21-11-2011, 20:16

Hi Marco

This all looks very promising from what i read so far, eager to read your review once the burn is done.
Looks like I've made the right decision once the extras arrive (Can't find a Furutech FP-682F(R) anywhere in the country), I'm waiting for Mains Cables R Us to get back.

Some photos would be nice just to get an idea of size, build etc.

For cosmetic reasons, Paul will be fitting mine into an Armageddon case with FI-09 Iec, CF-601M(R) and the above mentioned. May also look into having the output stage done in Silver wire etc as with the xl version.

Nothing like starting at the bottom and working your way to Audio Nirvana.:scratch:

ComradeSaigon

21-11-2011, 21:14

I do own a Paul Hynes MM phono stage. This product was many years ago when his company just start up.This guy is expert in power supply. Hence my phono stage transient is very fast and quite. I'm looking forward to getting a power supply from the man himself to fit into my Technics soon.

RotaryConnection

21-11-2011, 22:02

Dip in every now and then to see what's happening-much progress since I fitted a Kabusa p/s to my pair of Mk5s a few years back now..Just wish I had spare funds to catch up with the latest!
Marcos deck was impressive enough last Scalford, l hope to hear it at the next one with the latest additions. Good work!

Marco

21-11-2011, 22:21

Hi Gareth,

Dip in every now and then to see what's happening-much progress since I fitted a Kabusa p/s to my pair of Mk5s a few years back now..Just wish I had spare funds to catch up with the latest!
Marcos deck was impressive enough last Scalford, l hope to hear it at the next one with the latest additions. Good work!

Cheers, mate. Glad you liked my T/T last time. Hopefully when you hear it again next year you'll like it even more! :)

Marco.

Paul Hynes

21-11-2011, 23:37

Hi Marco,

The Clearsilver XL fine silver lead I sent you was terminated with silver plated contact XLR connector that I fit as standard on standard SR5 and SR7 power supplies. This was done so you could use it with the standard SR5 power supply.

I have not tried the Furutech connectors on this lead but would expect an audible upgrade over the XLR connector that I fit on the standard leads. The XL connector I fitted to your SR7EHD power supply was chosen because it has a contact resistance of less than 1 milliohm. It is a precision industrial connector that complies with military specifications across Europe and the USA. In other words it is a very good connector. I do not know how it will compare with the Furutech connector but if the Furuteck is a better connector I will be happy to fit this to power supplies on request.

I have been selling the Clearsilver XL cables for a long time on a custom build basis. The configuration of the triple core woven cable is not new. I just applied the parameters of cable construction that I felt were valid for very high quality sound reproduction. Basically a single solid core conductor per core using Fine Silver conductors and low-loss dielectric insulation. And a controlled annealing process to relax the molecular structure of the silver after cable construction.

I use the same physical configuration for DC power leads, signal interconnects, loudspeaker cables and mains power leads (with additional insulation layers to comply with safety regulations) but vary the core diameter according to the electrical requirements of the equipment the cable will be used with.

This cable construction satisfies my requirement for musical coherency in my system.

Marco

21-11-2011, 23:57

Hi Paul,

Many thanks for the info - noted. It'll be interesting to see which cable and sockets/plugs are best. I will report on the outcome when I've conducted the test :)

Marco.

MartinT

22-11-2011, 06:36

We were listening to Paul's Clearsilver XLR balanced cables between my preamp and power amp on Saturday and they were sounding mighty fine. I have ordered another set to replace the Canare cable between my phono pre and preamp.

Marco

22-11-2011, 08:59

We were listening to Paul's Clearsilver XLR balanced cables between my preamp and power amp on Saturday and they were sounding mighty fine

Yes, I'd forgotten about that; indeed they did! :)

Marco.

Marco

22-11-2011, 09:02

Hi Paul,

I meant to draw your attention to this which I wrote earlier in my mini review of the SR7:

Although such a huge power supply for the Technics is arguably WAY 'over the top', in terms of the measurable current it can draw (and some would therefore say unnecessary), listening tests clearly indicate that there are still significant sonic gains to be had by going down the over-specified transformer route. It is beyond question to my ears that, with the Technics SL-1200/1210, latent potential exists, waiting to be untapped, when the use of a judiciously over-specified external PSU is employed. Paul I'm sure will provide the technical rationale.

Perhaps for the benefit of people reading you could outline your rationale there? Churz! :cool:

Marco.

Paul Hynes

22-11-2011, 13:12

Hi Marco,

Firstly, any electronic circuit can be strangled by an inadequate power supply, and secondly, there is no such thing as a free lunch in power supply design.

The ideal power supply will have ZERO impedance at ALL load operating frequencies. It is not possible to generate any voltage change across a zero impedance source no matter how much current you pass through it. Therefore there would be no interaction between the power supply and the load. Unfortunately, this ideal power supply does not exist in the real world, as far as I am aware, as the available means of controlling impedance are not ideal.

Real world power supply designs differ enormously in their abilities. Power supplies are only as good as the designer’s acquired knowledge and his product budget at any given level. If you only have a budget of £35 for the material costs of the power supply design you are not going to come up with the finest power supply on the planet. If you insist on using industry standard three terminal regulators, because this is how you are taught at college or university, you are not going to get there either. In fact there is just as much performance variation from design to design as there is with amplifiers, preamplifiers, vinyl front ends, loudspeakers and digital electronics. It erroneous to class all power supplies as just power supplies as they radically affect the performance of the equipment they power.

So what is the rationale behind the SR7 range of power supplies?

The SR7 is a heavy-duty version of the SR5 power supply capable of powering anything from a Mac Mini to a power amplifier with the appropriate selection of components. The regulator circuit topology used in these power supplies has been designed from the ground up as a high performance DC amplifier with a wide AC load operating bandwidth, fast transient response and settling time, very high transient current delivery and very low wideband noise. This circuit topology is the result of many years of dedicated R&D aimed at approaching the ideal power supply performance as closely as possible. If I had a better topology for this application I would be using it.

The improvements over the SR5 come from :-

Increasing the size of the mains transformer. I have already described the mains transformer spec briefly on another thread. Essentially it is custom designed for optimum operation, avoidance of core saturation problems and low operating noise both electrically and mechanically. Making it larger means it has an easier time delivering the goods downstream.

A balanced rectification arrangement has been applied for both supply rails feeding the regulator circuit. The secondaries are always referenced to the 0 volt rail whether the rectifiers are conducting or not.

The energy storage capacitance has been increased by a factor of 4.

Some modifications to the regulator circuit have been applied but I am not at liberty to discuss these, as the regulator topology is the subject of consultancy client non-disclosure agreements.

The net effect of these changes is that the regulator circuit has an easier life as the quality of power that feeds it has been significantly improved, reducing any interaction between the two and load regulation has been improved. As you have found out you can hear this effect directly as improved sound quality in your system. The supply line rejection of the regulator is very good, and extends over a much wider bandwidth than other power supplies generally available, however this rejection is not infinite and this is why it is possible to hear improvements with transformer, rectification, energy storage capacitance and indeed regulator topology changes.

I hope this helps.

Regards
Paul

Mark Grant

22-11-2011, 14:06

Looks like I've made the right decision once the extras arrive (Can't find a Furutech FP-682F(R) anywhere in the country),

They are usually a special order item as the Furutech UK distributor does not have any in stock.

Marco had to wait a while for that one, it was easy to fit though:)

The other connector with threaded locking ring (not sure what its part number is) that Paul has fitted as standard does look high build quality so might be all you need.

This new PSU is a beast of a thing :)

MartinT

22-11-2011, 14:33

Marco - did we resolve why your SR-5 (and presumably your SR-7EHD) has a three-pin socket while my SR-5 has a four-pin? It made immediate PSU swapping impossible.

Paul - what is your standard socketry for PSUs intended for the Technics?

Paul Hynes

22-11-2011, 17:14

Hi Martin,

I usually fit the following :-

Standard power supplies.

For the SR3 power supplies a gold plated terminal Lumberg precision 4 pin DIN.

For SR5 and SR7 single supply rail power supplies a silver plated terminal 4 pin XLR

For SR5 and SR7 multi-rail supplies I fit silver plated terminal 4 and 5 pin XLRs in multiples as required.

The use of the 4 pin DIN and XLR is to avoid the possibility of plugging a 3 pin signal lead into the power supply.

XL power supplies (these XL connectors are not physically compatible with XLR connectors so no danger of plugging a signal XLR into the power supply)

For the SR3 power supplies a silver plated 3 pin XL connector.

For SR5 and SR7 single supply rail power supplies a silver plated terminal 3 pin XL connector

For SR5 and SR7 multi-rail supplies I fit silver plated terminal multi-pin XL connectors as required.

I do fit custom connectors as required by the customer as some have their favourite connector type.

I fitted a 4 pin XLR to your and Marco’s XL DC leads as you already had 4 pin XLRs on your SR5 power supplies. This was to allow Marco to assess the use of the Clearsilver XL wiring arrangement on his deck and was replicated for you.

Regards
Paul

Marco

22-11-2011, 17:39

Hi Martin,

Marco - did we resolve why your SR-5 (and presumably your SR-7EHD) has a three-pin socket while my SR-5 has a four-pin? It made immediate PSU swapping impossible.

When I ordered the Furutech XLR plug and socket, to replace what Paul had fitted to the SR5 as standard, as I like the Furutech stuff, I didn't consider the three or four pin thing, so the Furutech plugs Mark ordered (and fitted to my PSU) had 3-pin connections (something I didn't know myself until you found it!) which is why you encontered the problem on Saturday :)

Marco.

Artifolk

22-11-2011, 18:45

They are usually a special order item as the Furutech UK distributor does not have any in stock.

Marco had to wait a while for that one, it was easy to fit though:)

The other connector with threaded locking ring (not sure what its part number is) that Paul has fitted as standard does look high build quality so might be all you need.

This new PSU is a beast of a thing :)

Thanks Mark,
I spoke to David (told me the same) over the phone early last week, but have heard nothing since.

I can source one from Germany, but I'll wait a little longer for David.

One question for Paul

I noticed that you place the heatsink on the front panel, this is not going to be possible with the Armageddon case, will you be placing it inside?

Charles

Paul Hynes

22-11-2011, 19:19

Hello Charles,

As the average current drawn by the SL1200/LSL1210 is low, this power dissipated in the output stage and rectification stage will be correspondingly low. I may be able to use the case as the heatsink or add a smaller heatsink internally. Either way, rest assured it is not something for you to be concerned over.

Regards
Paul

MartinT

22-11-2011, 19:25

I fitted a 4 pin XLR to your and Marco’s XL DC leads as you already had 4 pin XLRs on your SR5 power supplies. This was to allow Marco to assess the use of the Clearsilver XL wiring arrangement on his deck and was replicated for you.

All clear now, thanks Paul.

MCRU

23-11-2011, 20:50

Thanks Mark,
I spoke to David (told me the same) over the phone early last week, but have heard nothing since.

I can source one from Germany, but I'll wait a little longer for David.

One question for Paul

I noticed that you place the heatsink on the front panel, this is not going to be possible with the Armageddon case, will you be placing it inside?

Charles

I sent you an e-mail to say it would be 2 weeks kind sir so I have ordered you one and some spares for my own power supply's as I also ran out! Will let you know once it's here.

MCRU

23-11-2011, 21:04

MartinT

23-11-2011, 21:22

MCRU

23-11-2011, 21:25

Would that be the cable that Marco brought round that I could hardly bend? The one that was a bugger to install behind my rack? The one that could do a good job as a suspension cable on the Forth Road Bridge?

Probably Martin and I found that out for myself but will only say 2 things about it, once you get it in place it stays there and it sounds stupendous!

Wakefield Turntables

23-11-2011, 21:26

MartinT

23-11-2011, 21:28

Probably Martin and I found that out for myself but will only say 2 things about it, once you get it in place it stays there and it sounds stupendous!

You're not kidding! It did sound good, though :)

Marco

23-11-2011, 22:36

Marco,
Nice thread and am glad your new PSU is doing the business, superlatives abound but there has been no mention of the mains lead that I can see connected to the PSU and which must surely be contributing enormously to the exceptional performance you are getting from this new item?

If you have mentioned it please excuse me as it's been a long day!

P.S Don't you have a cleaner in your house to deny those dust mites a hearty meal? :lol:

What say you matey? :)

http://i622.photobucket.com/albums/tt309/themainsman/14d57a07.jpg

Lol! Oh the 'Ultimate' power cable, purchased from your good self, is definitely playing an essential role in proceedings, as are the others in my system!! :eyebrows:

Full review on David's Ultimate power cables to come during the Xmas hols, folks (which for me begin on 16th Dec)! :christmas:

Marco.

Artifolk

24-11-2011, 11:06

I sent you an e-mail to say it would be 2 weeks kind sir so I have ordered you one and some spares for my own power supply's as I also ran out! Will let you know once it's here.

Thanks you kind sir.

Rhodium/Silver

Looking forward to the outcome of the two connecting methods. i have a feeling Paul's xl plug will be the winner. For some reason i can't get my head round Furutech using Rhodium as Silver is a far better conductor of Electric, but the taste is always in the eating, so to speak. Just remember to keep those Silver connectors clean.:doh:

Artifolk

03-12-2011, 15:48

Hi

Thought I'd let you know.
I've just placed my order with Paul for a SR7EHD PSU, now I've just got to sit back await... this is going to be a long time due to Christmas just around the corner.
I went for the XL connector, Fine Silver lead, Silver internal wiring from the regs to XL panel connector and Furutech FI-09 IEC
Thank you Paul for all your help.

I'll post some pics when it arrives(I'll ask Paul first tho).

Now off to study up on the Bearing etc.

Marco

06-12-2011, 00:04

Nice one, Charles! Trust me, you won't regret it :)

I've been living with the SR7 now for a couple of weeks, and it has definitely added another dimension to the sonic performance of the Techy; really 'tidying up' its sound, making it bolder and more 'grown-up' than ever, and thus elevating the Technics further into the realms of being a truly world-class T/T.

When I got the SR7, it was around the same time as I obtained my new Ortofon tonearm, so it wasn't so easy to ascertain exactly where the huge improvement in the sonic performance of my T/T was coming from. Undoubtedly, the RS212D was making a significant contribution, as was the SR7.

However, it wasn't until I had the (now well-documented) mishap with my Ortofon arm, and had to return temporarily to using a Jelco SA750, that I was able to appreciate the sheer musical magic that the SR7EHD was clearly bringing to the party - a magic which simply wasn't there to the same degree before with the (excellent in its own right) SR5, in the exact same system.

The SR7EHD allows the Techy to significantly better resolve information on recordings and present it with unflappable ease, finesse and unbridled clarity. Basically, it provides insight into all genres of music on vinyl that I've not heard so far from any other high-quality off-board T/T for the SL-1200. As such, it qualifies as one of the most fundamental upgrades one can buy for the Technics. Paul has created an absolute gem with this one! :cool:

What you need now is one of Mike New's superb bearings - quite simply, there is nothing else on the market for the Techy to touch them...

Marco.

Artifolk

06-12-2011, 19:30

Thanks Marco

I'm really looking forward to this build.
Can't wait to get the PSU... still waiting for Paul to confirm he received payment etc, left an email but haven't heard so far... Busy man.
Any comment on the Furutech vs Pauls XL socket. I've missed out on the Furutech as David reckons they've stopped manufacture...GRRR:lolsign:

From what I've read so far, reviews etc, it would seem the Mike New bearing is the one to get, but before i do make a decision, I'll prob go for the internal regs first, get the power up to or at least its best then move on to the bearing.

Also from what i can gather, I've possibly made a mistake with the Oyaide mat (fantastic btw) but i can at least sell it on. What with the Mike New Platter and Funks version.( looking forward to a review).

Paul Hynes

06-12-2011, 19:43

Hi Charles,

Payment confirmed. It has been a little busy lately. I still have a lot of e-mail to answer and I have to fit this into gaps in the work schedule. Will get back to you shortly.

Regards
Paul

Marco

06-12-2011, 20:14

Hi Charles,

Unfortunately I haven't had a chance yet to compare the Furutech vs Paul's XL socket. It's not a quick one to do.

However, I can say with some confidence that, if there's anything in it, it will be very small. Therefore since the Furutech is no longer available, I'd simply go with Paul's XL plug and socket, and enjoy! :)

The Mike New bearing, at the moment, quite simply has no real competition, so that one's an easy decision to make.

As for the Oyaide mat, you haven't made a mistake. It forms a formidable partnership with the stock platter (I've used that combo before, so I know exactly what it does), but if you really want to take the Techy all the way, sonically, then the Funk or Mike New's platter is the way to go.

Marco.

Wakefield Turntables

06-12-2011, 20:22

Artifolk

07-12-2011, 18:33

Thanks Paul.

Could you also let me know the costs of the internal regs upgrade. Maybe i could add this to my order?

Marco

I possibly should have rewritten what i was saying about the Oyaide.

I should have said... its a fantastic mat but i wish i had found this site before buying.

Paul Hynes

08-12-2011, 11:28

Paul,

That’s what I do to the office computer when things go wrong, only I use a big stick.

I will be making your power supply once the custom Teflon printed circuit board (PCB) arrives. There are a number of different specification levels for the materials used to make Teflon boards. This is special order stuff from abroad and at this specification level the board material itself is only manufactured to order. The board material should be arriving at my PCB manufacturer any day now and will be processed within a week of arrival. I did warn you it would be after the Christmas/New Year holidays before I would be finishing your power supply. I know it is hard waiting for toys, as I am about to order one that will take around 8 weeks to arrive. This is just the way custom built to order is. :painting:

Charles,

I have e-mailed you with details of the internal regulator upgrades.

Regards
Paul

MartinT

08-12-2011, 13:17

On the subject of the internal regs, Paul, I shall be starting them very soon now, once I have this very busy week behind me.

Wakefield Turntables

08-12-2011, 19:51

Paul,

That’s what I do to the office computer when things go wrong, only I use a big stick.

I will be making your power supply once the custom Teflon printed circuit board (PCB) arrives. There are a number of different specification levels for the materials used to make Teflon boards. This is special order stuff from abroad and at this specification level the board material itself is only manufactured to order. The board material should be arriving at my PCB manufacturer any day now and will be processed within a week of arrival. I did warn you it would be after the Christmas/New Year holidays before I would be finishing your power supply. I know it is hard waiting for toys, as I am about to order one that will take around 8 weeks to arrive. This is just the way custom built to order is. :painting:

Regards
Paul

No worries mate, I just cant wait to get the beast in the system!

On the subject of the internal regs, Paul, I shall be starting them very soon now, once I have this very busy week behind me.

Hurry up and get these installed, I cant wait to see what differences they make. :lolsign:

Artifolk

08-12-2011, 20:05

Charles,

I have e-mailed you with details of the internal regulator upgrades.

Regards
Paul

Thank you

Hurry up and get these installed, I cant wait to see what differences they make. :lolsign:

Second that.

jostber

03-01-2012, 17:38

Has anyone tested the difference between the XL and XLR connector options in the SR7EHD? Since the XL is more expensive is this upgrade worth it?

MartinT

03-01-2012, 17:44

Hurry up and get these installed, I cant wait to see what differences they make. :lolsign:

I've made a start! From here: http://theartofsound.net/forum/showthread.php?p=279138#post279138

The two-stage split 21V setup is sounding absolutely superb.

Wakefield Turntables

03-01-2012, 21:54

Martin,

Just how many bloody stages are there to this regulation lark?? :eyebrows:

Any comments on how they have improved your deck?

I'm now very very envious :D

MartinT

03-01-2012, 22:32

Marco

04-01-2012, 09:27

Hi Martin,

This definitely offers a heightened sense of pitch stability, inner detail and resolution, fantastic dynamics and lowered noise floor

Interesting... That's *precisely* what the SR7EHD brings to the party! It'll be intriguing to see what further improvements are wrought by further mods :cool:

Marco.

Wakefield Turntables

04-01-2012, 14:59

Andrew

Briefly:
1) Single-stage external 21V supply
2) Dual-stage external 27V and internal 21V supplies
3) Dual-stage external 27V and dual internal 21V supplies splitting motor control and motor drive (this is currently where I'm at)
4) Triple-stage external 27V, dual internal 21V and extended 9.4V & 5V supplies

I've commented in the other thread on how it sounds (http://theartofsound.net/forum/showpost.php?p=279735&postcount=89)
This definitely offers a heightened sense of pitch stability, inner detail and resolution, fantastic dynamics and lowered noise floor. I really don't know what moving from 3) to 4) will bring, but I'll be tackling it very soon.

Man this really is killer! Cant wait to get my hands on these.

Hi Martin,

Interesting... That's *precisely* what the SR7EHD brings to the party! It'll be intriguing to see what further improvements are wrought by further mods :cool:

Marco.

If that's what the SR7EHD fetches to the party I'd hate to think what the XL version offers:lol: I'll be posting some findings when I recieve it.

Marco

04-01-2012, 15:02

Lol - I doubt we'll ever know what the difference is unless we swap PSUs at some point.

Could be a plan? :cool:

Marco.

Wakefield Turntables

04-01-2012, 16:32

MartinT

04-01-2012, 16:53

I've already been warned that the beast is gonna be big!

There's my excuse for not upgrading from the SR5. Damn, I'm not convinced...

Wakefield Turntables

04-01-2012, 17:35

There's my excuse for not upgrading from the SR5. Damn, I'm not convinced...

Do you really need to, after all those regs?

MartinT

04-01-2012, 17:46

Honestly - I don't know. I'm going to get the third stage regs done before I even think about it, though.

Marco

04-01-2012, 21:09

I still havent got the bugger yet and your already wanting mine :ner: I really want to see what the differences are between the current PSU (Timestep HE) and Paul's, I've already been warned that the beast is gonna be big! I may have to buy another rack for the stand :lol:

Lol - I'm not after anything, dude. I'm more than happy with the 'mere' standard SR7EHD! :eyebrows:

All I was suggesting is that it might be interesting swapping PSUs for a week sometime later on, as that way we can analyse the sonic effect of the 'posh bits' you've had put inside yours :cool:

Marco.

Marco

04-01-2012, 21:12

There's my excuse for not upgrading from the SR5. Damn, I'm not convinced...

Trust me, if I popped down and let you hear my SR7EHD, it'd take you around 5 secs to understand why it's fundamentally better than the SR5, and indeed what makes it rather special - that is after you've scooped your jaw up off of the floor!! :eek: :wowzer:

Marco.

MartinT

04-01-2012, 21:14

It'll be more difficult these days, Marco. Not only do you have a different connector, but I need 27V rather than the normal 21V for my deck now.

Paul Hynes

04-01-2012, 23:09

Marco’s SR7EHD can be adjusted to 27 volts output internally and I can provide a new lead with the requisite connectors if required.

Happy New Ears folks.

Regards
Paul

Artifolk

05-01-2012, 05:43

I'm also getting itchy waiting for mine to arrive. Specially after what Mikes Bearing has done to the deck.
And with all your help i should be able to turn this into something special.

22 years with a Linn and now my eyes have been opened.

Paul.

Hope the case arrived intact?, I haven't sent the front panel as i was worried it may get damaged, also would it be possible to keep all the connection/Switch to the left and right hand sides as my Fraim(Rack) is a tripod design.

This upgrading lark is very infectious. :eyebrows:

Marco

05-01-2012, 09:22

Hi Paul,

Marco’s SR7EHD can be adjusted to 27 volts output internally and I can provide a new lead with the requisite connectors if required.

Interesting. A couple of questions, if I may...

1) What are the sonic advantages (if any) of adjusting my PSU to 27 volts output? Or what is the actual purpose of adjusting the voltage?

2) Why would a new DC lead be necessary - couldn't I adjust the voltage and keep my existing lead? Or would the new lead you're proposing simply be to facilitate Martin and me swapping PSUs? :)

Happy New Ears folks.

Lol - same to you, my friend! :cool:

Marco.

MartinT

05-01-2012, 09:57

Marco - the Technics main DC power rail must be run at 21V. This is why most external PSUs (such as yours) are set to 21V.

My deck now has internal 21V regulators so this is why an external 27V rail is required (this is two-stage regulation). You could not now use my PSU on your deck.

Marco

05-01-2012, 10:13

H'okey cokey... So, apologies for being dense, but what was Paul getting at with his suggestion of a new lead?

Anyway, there's one sure way to sort this...

I'd forgotten that I still have my SR5, therefore all we have to do, is for me to bring it down (along with my T/T) and let you hear the comparison between the PSUs, using my T/T in your system, which will easily show up the differences!

All you have to do then is listen to the sound of my T/T with both the SR5 and SR7EHD, using your system as the reference point, and judge from that.

Job done :cool:

Marco.

MartinT

05-01-2012, 11:52

I don't doubt that the SR7EHD sounds better than the SR5 when used as a single external power supply on your deck. However, working out whether it will sound better on my deck (with, eventually, triple stage regulation) is more complex than that and necessitates the use of 27V external PSUs - with my deck, of course :)

This is why Paul is suggesting the adapter cable - so that we could adjust your SR7 to 27V and use the cable to connect it to the 4-pin flying lead from my deck.

Paul Hynes

05-01-2012, 12:29

Hi Marco,

Martin has answered your questions but for technical reference I have added some more information below.

The output voltage should only be adjusted to 27 volts if the SL1200 internal regulator upgrades are in place. All regulators have what is called a dropout voltage, which is the required voltage between input and output to maintain voltage regulation. The regulator will not regulate if the input to output voltage is reduced below the dropout voltage. The PR3 regulators fitted in the transformer well of the chassis have dropout voltage of around 4 to 5 volts in this application so the external power supply needs to be set higher to ensure correct regulation.

Martin’s SR5 was fitted with a 4 pin XLR originally. You have changed the SR7EHD XLR to a Furutech XLR which, I believe, is a 3 pin XLR. Unless Martin has also changed to a Furutech 3 pin XLR your connectors will not be compatible. I will have to make a 3 pin XLR cable the same length as his 4 pin cable for Martin to patch into his deck wiring. This will provide the minimum number of contacts in the DC path. I will need to know which pins have been used on the three pin XLR to ensure correct polarity.

Charles,

The case arrived yesterday. I have not checked the parcel yet as I have only returned to work today and there is a very large e-mail in box to get through. Many of the materials orders that were delayed by bad weather during December and the holidays have also arrived and I have to get these unpacked, checked and sorted for the various build projects in the build schedule. It will probably be Monday before I get into the workshop and I will be working through the build schedule in chronological order as usual.

Andrew,

The Teflon printed circuit board has arrived. I will be building a large batch of regulator modules for a variety or power supplies including yours next week and then working through the outstanding power supplies.

Regards
Paul

jostber

05-01-2012, 16:27

Great to see that good craftsmanship is in demand! :thumbsup:

Artifolk

05-01-2012, 19:47

Paul,

Thanks for confirming delivery.

Happy New Year

Wakefield Turntables

05-01-2012, 20:37

Lol - I'm not after anything, dude. I'm more than happy with the 'mere' standard SR7EHD! :eyebrows:

All I was suggesting is that it might be interesting swapping PSUs for a week sometime later on, as that way we can analyse the sonic effect of the 'posh bits' you've had put inside yours :cool:

Marco.

I'll be doing a slow upgrade over the next six-nine months starting with a new cart, new SUT and some lovely new reference power leads for my ATC's. I'm gonna see what each bit adds to the system, I'll probably also put in the new internal regs that Paul's designed but we'll have to see about that later! I'm very much up for fetching the PSU to you at some point. Probably meet you half way somewhere at a hifi show??

This upgrading lark is very infectious. :eyebrows:

You poor dude! :D You have techy1210itis which is a commonly known disease amongst the bretheran of AOS. There is no known cure and you'll always be skint but you will have a wonderful deck.

Hi Marco,

Andrew,

The Teflon printed circuit board has arrived. I will be building a large batch of regulator modules for a variety or power supplies including yours next week and then working through the outstanding power supplies.

Regards
Paul

:yay::yay: NICE! Now, when can we start to buy the internal regs from you :scratch:

Artifolk

05-01-2012, 21:10

You poor dude! :D You have techy1210itis which is a commonly known disease amongst the bretheran of AOS. There is no known cure and you'll always be skint but you will have a wonderful deck

Who needs a cure when fully blown techy1210itis is the outcome :facepull::lol:

MartinT

03-09-2012, 17:46

I rushed home tonight to get Paul's latest wonder PSU installed. The SR7-27 (set for 27V because I have the full dual-stage regs fitted internally) is a big beast, fitted into a silver chassis but with the mammoth heatsink deleted as I needed it to fit into the tight space available in my system rack. It's quite a lot larger and heavier than the SR5.

Now I must admit to wondering whether the SR7 would really yield any improvements over the already over-spec SR5, however I remembered the very significant uplift in performance of the SR5 over the SR3 and Timestep PSUs, so I went ahead and ordered it knowing what it was doing for Marco's deck.

I am not disappointed. There are improvements across the board (no night-and-day stuff, this is subtle) and, interestingly, the first thing I noticed was a cymbal in the opening to Gaucho that I hadn't really focused on before. There is more authority, more of that rhythmic-metronomic punch that the Technics does so well, more detail in the soundstage, more slam.

I am listening to it connected via the 4-pin XLR connector, just to get the thing going. I have yet to fit the 3-pin Jaegar connector that Paul assures me delivers an even lower output impedance.

I can't begin to figure out how a hugely over-spec PSU can better an over-spec PSU when there are two further stages of regulation down-line, driving a turntable motor. All I can say is that the SR7 is the best PSU I have heard on my deck, taking its performance even higher and representing (in my book) good value for money.

Wakefield Turntables

03-09-2012, 18:03

Welcome! Did you get the XL version??

MartinT

03-09-2012, 18:10

SR7-27 EHD.

Wakefield Turntables

03-09-2012, 18:11

mines stupidly over specced but useless at this moment in time :( Paul has my deck and he's waiting for me to send him a replacement PCB, just you guys wait till my baby comes back!

MartinT

03-09-2012, 18:15

We're waiting, Andrew. Seems like an age since you were last playing it. Expensive mistake :steam:

synsei

03-09-2012, 18:25

Expensive mistake :steam:

Which is why you won't catch me doing such things to my Techie. When it comes to electronics mods I'm best kept well out of the way as I'm likely to blow something up just by being near it :lol: I'll pay someone to do it for me if or when the time comes... ;)

MartinT

03-09-2012, 18:35

Paul has set up agent(s) in order to have the mods performed for you, when you're ready Dave.

synsei

03-09-2012, 18:42

Cheers Martin, but I've a long way to go yet. I do have an external PS now which has made a huge difference. I can't stop listening to my vinyl these days... :D

MartinT

03-09-2012, 18:47

Me too - that's what it's about!

MartinT

05-09-2012, 17:29

The SR7 has certainly brought its prize to my consciousness over the last couple of days, a combination of a) having run-in for 48 hours and being thoroughly warmed through, and b) my listening to a goodly selection of great music, hearing much of it in a new way.

As I first stated, it seems to be the treble that reveals itself first, being ultra clean, pure and filigree detailed. Then comes the incredible punch to anything percussive. Just now I've been hearing more and more that my speakers simply disappear, there being no sense of two channels of sound, just a deep and wide stage in front of me. My insight into the music is the best I've heard, a very strong sense of presence in the best recordings and at the very least something interesting about the worst recordings always coming through.

I don't know how he does it or exactly what's different about the SR7 over the SR5 (I would guess tighter regulation and more instantaneous current capability, possibly lower noise), but Paul has created yet another great enhancement to the Technics turntable. The very fact that the Techie keeps responding to these upgrades by getting ever better is a real testimony to how good the basic design is. Perhaps the improvement in treble is down to a further reduction in flutter? I'll also lay more than a little of the quality of the overall sound at my Dynavector arm's door. More fool HFN who gave it a so-so review. It is simply in a different class from the various SMEs.

So thank you, Paul. I am extremely happy with the SR7 and consider it to have been money very well spent.

Marco

06-09-2012, 23:01

Sorry I'm late to this one, Martin. Well done!

It's amazing how Paul's internal reg mods and the SR-7 work together so symbiotically, isn't it? :)

Marco.

Paul Hynes

07-09-2012, 10:36

Hi Martin and Marco,

Both of you are well aware of the benefits of a larger power supply and Marco is right about the symbiosis of the whole power system.

This particular regulator circuitry responds well to cascading in series and using this technique provides enormous supply line rejection making the deck circuitry much less susceptible to mains borne interference. Cascading regulators can add the regulator sonic signatures but in this case the regulator signature is benign so the technique is beneficial. This is not true for all regulator circuits and cascading some of them can add sonically obnoxious characteristics.

The regulator modules and power supplies are very quiet so they are not introducing high levels of additional noise on the motor board. They also operate over a much wider bandwidth than the typical regulator circuits used in audio power supplies, so RFI rejection is good and the regulators are still effectively regulating the digital control circuitry in the SL 1200, where lesser regulators like the LM317, and it’s clones, have stopped regulating as they have run out of bandwidth.

Not only that, the internal regulator modules are closer than any external power supply can be to the load circuits, so the load regulation is more effective.

Most people would consider the SR7 to be grossly over-specified for the SL1200, however there are audible gains to be had by the improved regulation and lower impedance of the larger mains transformer, the reduction in output impedance by increasing the size of the output stage and up-rating the rectifier diodes. More power under the bonnet, so to speak. There are also a few little tweaks to the circuitry that I am not at liberty to disclose at present.