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MartinT
29-06-2011, 19:09
Just how much difference can a step-up transformer make? After all, the CineMag step-up transformers I’ve been using are not too shabby and are well regarded in the forums as a bit of a bargain. So can a SUT make enough difference to justify spending any more? Read on to find out.

Hashimoto

Hashimoto are a Japanese transformer manufacturer, originally formed from Sansui employees when that company decided to cease production of transformers in-house. The best employees moved over to Hashimoto and continued their great work in designing and selling transformers, much of it initially going back to Sansui. It was said that the custom hand-wound transformers provided by Hashimoto were the secret to the success of the revered Sansui AU-111 valve amplifier from 1965. When Sansui closed their doors in 2001 as a manufacturer, Hashimoto had established their business selling high grade audiophile transformers as OEM products.

Choir Audio

John Parker, of Choir Audio, builds complete step-up units using some of the best transformers in the business, including the aforementioned CineMags and Hashimotos. He has been selling the SUT-H based on the Hashimoto HM3 transformers and is now the first manufacturer to build a complete unit, the SUT-H7, based on the new flagship Hashimoto HM7 transformers.

The SUT-H7 is built using ‘six nines’ OFC silver-plated copper wire with Teflon insulation. Mine is finished with Cardas phono sockets, but WBT can be specified as an alternative. The unit is substantially cased in a black finish and is quite large as SUTs go, weighing 2kg.

Choir Audio built my SUT-H7 to order and despatched it across the Atlantic within a couple of weeks. Communications from John have been excellent at every stage of the order process and he was a delight to deal with.

http://www.mtc.me.uk/images/ChoirSUTH7_1.jpg

Switches & Loading

There are switches for each channel providing loads of either 2-7 ohms with +29dB gain or 7-40 ohms with +23dB gain. As I found out, it’s best not to get too hung up on the loading specifics for a given cartridge and try them both out. For example, an AT-33PTG has a coil impedance of 10 ohms but requires a load impedance of “greater than 100 ohms”. This would suggest that I should use the low gain setting, but in fact high gain position sounded better. The Shelter 5000’s loose interpretation of ‘instructions’ suggests a step-up load of 20-40 ohms. Despite this, both cartridges sounded best in the 2-7 ohm setting.

The recommended loading impedance for the SUT-H7 is 47k ohms, the standard for phono preamps. I set my Whest preamp for this load and a gain of 40dB. This latter was decided on as I preferred the SUT-H7 in the high gain position and the Whest clipped when set for 50dB gain, so 40+29=69dB overall gain suited my system.

The more I experiment, the more I come to the conclusion that higher gain in the SUT and correspondingly lower gain in the phono preamp is best for sound quality, so this is how I tend to set my system up these days.

Why Use a Transformer?

I’m aware that my Whest Audio PS.30R phono preamp is capable of taking low output MC cartridges directly, and has flexible loading and gain controls for just this purpose. However, the whole reason for the existence of step-up transformers, and their apparent complexity due to yet another device introduced into the replay chain, is that they sound so incredibly vivid and dynamic when compared with active MC inputs. They also don’t generate much additional noise due to a lack of any active components. I believe that impedance matching is the key; furthermore, a transformer is able to utilise the whole energy output of the cartridge, which is generates high current at very low voltage into a higher voltage signal suitable for a standard phono stage. A phono preamp’s MC stage throws away the cartridge’s current generation (with the notable exception of the Dynavector’s P-75 phono enhancer mode) and starts from a tiny voltage. It is this whole energy preservation in a SUT, something top end MC cartridges have in abundance, that creates such excitement and dynamic prowess in their music making and sets high end vinyl playback aside from any other source.

Cabling

I connected the silver Dynavector arm cable into the SUT-H7 and then a 0.5m length of Mark Grant G2000HD from there to the Whest phono stage. The rest of the system uses Kimber Select balanced interconnects and speaker cables.

Sound

John recommended 30-50 hours of running-in time before the SUT-H7 would give of its best. Putting the SUT-H7 into circuit in place of the CineMags, I was immediately confronted with explosive dynamics and more dynamic contrasts than I’ve frankly heard in any but the most high end horn systems. This was accompanied by wider soundstage and far more precise placement of instruments than I am used to. Surface noise was very low and pops and clicks were banished to virtually inconsequential on most of my records.

There is greater depth, not in the front-to-back dimension but in how music stands out from the background. Everything is more out of the box – solid replay right there, enough to reach out and touch.

Difficult but well-known tracks like ‘Whole Lotta Love’ from Led Zeppelin II and ‘With or Without You’ from U2’s The Joshua Tree sprung into life with a zest and vividness that had me laughing out loud.

‘And I Stoned Me’ on Van Morrison’s Moondance can sound a dreadful mess on many systems. His penetrating vocals are a constant but what impressed me were the drums brought forward in the mix and the lifting of the whole piece into something resembling a live performance. Next up, another difficult track is ‘Go Home, Girl’ from Ry Cooder’s Bob Til You Drop. This very early digital recording can sound flat and two dimensional but was a revelation through the SUT-H7 using the Shelter 5000 cartridge. Clive Gregson and Christine Collister’s Mischief is recorded a little hot and up-front, but again strands of the music were separated out and the whole thing sounded vivid and alive.

Trying some more classic tracks, ‘Moving’ from Kate Bush’s The Kick Inside brought her voice right out stage front, yet the drums and cymbals were also projected in typical late 1970s style. From the same era, Joan Armatrading’s eponymous album leaves all others for dead, certainly on this reckoning with stunning acoustic guitar and, again, highly projected and expressive voice.

One of my favourite tests is pretty much the whole of side 1 of Santana’s Abraxas. The lead-in ‘Singing Winds, Crying Beasts’ with its gentle piano and incredibly realistic wind chimes didn’t prepare me for the lengthy, hugely penetrating note from Carlos’ Strat, once again challenging my volume setting. Further in, the stage-right percussion work in ‘Oye Como Va’ was simply fabulous.

Many more songs reinforced my complete enjoyment of the SUT-H7’s contribution to the new sound of my system. Switching from the AT-33PTG to the Shelter 5000 just upped the level again in all aspects: midrange transparency, treble sweetness and extension and a sense of swell that remained ever dangerous. The sound settled down after about 50 hours of use, as John predicted.

http://www.mtc.me.uk/images/ChoirSUTH7_3.jpg

Conclusions

If anyone had told me before receiving the SUT-H7 that I would, as a result, rework my phono system hierarchy I would have been surprised. But here it is: turntable > arm > SUT > cartridge > phono amp. The Choir Audio SUT-H7 has unlocked the potential of my already very capable front end in a way that no cartridge, and I mean no cartridge, could ever have achieved. I feel that, after some 35 years of system building, I have finally achieved high end sound. The SUT-H7 is that good.

I wasn’t sure what to expect when I read Choir Audio’s warning “Please make sure that your source is up to the task as the HM-7 is very revealing and will uncover any weak links in your source components”. I needn’t have worried. In the context of my overall system, and understanding that some will dispute my use of the word, the SUT-H7 is an absolute bargain and has given me more musical nirvana than any other component change could have achieved.

Test system

Heavily modified Technics SL-1210 turntable with Dynavector DV-507II arm, Shelter 5000 and Audio Technica AT-33PTG cartridges. Whest PS.30R phono preamp, Pass Labs XP-20 preamp and Chord SPM-1200E power amp. Usher Dancer Be-20 speakers. PS Audio Powerplant Premier mains regenerator.

Competitive equipment: Bob’s Devices CineMag SUT, Whest PS.30R (direct in).

Price $1,499

Available direct from Choir Audio, USA:
http://www.choiraudio.com/

John
29-06-2011, 19:17
John seems a real gent he makes some lovelly looking turntables too I hope he decides to join here as over on the Hawnthorne site his comments are good and he has a good knowledge around design I am really happy it worked well

Alex_UK
29-06-2011, 19:55
Excellent review, Martin and even though it doesn't have any direct relevance to me (yet!) I still read and enjoyed every word of it. Aesthetically, it also compliments your Techie rather nicely, and it sounds like you are a very happy chappy, so enjoy!

Marco
29-06-2011, 22:17
Fantastic review, Martin - superbly written, and with beautiful photographs. It doesn't get much better, mate - perhaps other than listening to the Hashimoto itself!

I wonder if it'll 'like' my SPU? I guess that there's only one way to find out.... ;)

Enjoy!

Marco.

P.S I note that Choir Audio have now joined the party :cool:

MartinT
29-06-2011, 22:31
P.S I note that Choir Audio have now joined the party :cool:

Good, I was hoping that I could persuade John ;)

Barry
29-06-2011, 22:47
Excellent review Martin,

I'm equivocal about the use of SUTs or SS pre-pre amps. At the moment I would say it a question of "horses for courses", but I have yet to do some serious analysis (and yes folks, that would be both objective and subjective).

Regarding your comments on Ry Cooder's 'Bop Till You Drop'. Well I have always regarded it as one the worse possible examples of digital recording: flat, two-dimensional soundstage with no 'tangability' whatsoever of the musicians. Your post has encouraged me to play the LP pressing again with my most recent of equipment to re-assess, and possibly revise, my opinions.

Re. Santana's 'Abraxas' - what a perfect record that was! Not only in the way one track segués into the next (well, on Side 1 at least), but as you say for the opening track 'Singing Winds, Crying Beasts': an album that should be in everyone's collection.

Will revisit Van Morisson's 'Moondance' based on your experience, though my copy is on CD.

Thanks for an excellent and well-worded review.

Regards

MartinT
30-06-2011, 05:36
I wonder if it'll 'like' my SPU? I guess that there's only one way to find out.... ;)

Perhaps if you can borrow a Homage we can have a SUT shootout later this summer?

MartinT
30-06-2011, 05:44
Regarding your comments on Ry Cooder's 'Bop Till You Drop'. Well I have always regarded it as one the worse possible examples of digital recording: flat, two-dimensional soundstage with no 'tangability' whatsoever of the musicians. Your post has encouraged me to play the LP pressing again with my most recent of equipment to re-assess, and possibly revise, my opinions.

Hi Barry, I was minded of your previous observations when I was listening to it. I can tell you that the CD is far inferior (madness!) so don't judge Bop Til You Drop on that. Take a listen to 'Go Home, Girl' and hear how gently it starts, lulling you into a high volume setting. The musicians and Ry's voice are well positioned in space and the background vocals towards the end of the song are set behind them. The guitars are simply superb, with all the metallic leading edge you could hope for but not at all harsh. By the time the band are in full tilt it sounds incredible, infectious and engaging. Tiefenbrun would be proud of my foot tapping.

I'll bet that early 3M gear could fill a room but it's clear to me that this digital recording captured an awful lot for such an early effort. I encourage anyone who doesn't have this album to find a vinyl copy of it.

Ammonite Audio
30-06-2011, 06:38
I am really tempted to have build myself a SUT using the Hashimoto HM-3, following Martin's experience. The HM-7 doesn't seem to be available anywhere.

Dominic Harper
30-06-2011, 07:13
Great review! I have also been looking at those transformers to build a SUT for customers.

Mike_New
30-06-2011, 07:18
Hi Martin,
This is bad stuff for me, now I must bite the bullet and order a pair of H7s.
to replace the ones in my WD phono amp, or get the complete unit as you have.

The one thing that bothers me is the minimum length of interconects that are available commercially.
I am going to get a quote from John to make me a special 2foot set for both the inputs and outputs, this way I can keep the wire length to a minimum between MC and phono amp.

Mike_New
30-06-2011, 07:28
I am really tempted to have build myself a SUT using the Hashimoto HM-3, following Martin's experience. The HM-7 doesn't seem to be available anywhere.

Hi Hugo,
The H7s cost $800.00 Inc postage

They are available from:------
Isao Asakura

CEO, President
SoundTradition
OBS, Inc.
P.O. Box 616
Lawton, MI 49065 USA
support@obsinc.us
Web Site:

http://www.tube-amps.net

http://www.sansui.us

http://www.obsinc.us/Dep_VOVS_Literatures.htm

The WD phono amp is I believe an excellent design, but the box it comes in maybe a bit small for the H7s which is my problem.

The other problem is that I do not believe the kits are available any more, but the circuits are freely avalable.

The Grand Wazoo
30-06-2011, 07:37
Great stuff Martin.
I have some fun in my search for the best SUT I could find, but I wish it hadn't taken so bloomin' long as it did!

Those transformers of yours have a very distinguished lineage. I don't think many people in the UK appreciate the significance of transformers to the Sansui brand. Tango transformers have a very good reputation, but back a while, Japanese DIY'ers bought only Tango's if they couldn't afford to buy the superior Sansui's.

I was helping Robert (Retro) to produce an article for the library about Sansui and we were getting close to finishing it, but Robert seems to have disappeared, so the piece never reached completion.
However, in our research, I learnt some things about the Sansui trannies - I hope Robert won't mind me quoting some parts of what we wrote:


During the early 1940’s Khosaku Kikuchi was an employee of an electronics component distributing company, supplying parts for radios to the trade. He was struck with the poor quality of much of what was being offered and so decided to become independently involved in the production of his own higher priced but better quality components.

He formed a new company at the end of 1944 in Yoyogi, a district of Tokyo and the name Sansui Electric Production was chosen. The word Sansui is translated as ‘Mountains and Water’ and the company philosophy was reflected in the Sansui style of ink painting which produces landscape designs (mountains and water) to represent the ‘principle of universal transformation’. The first products were transformers.

The company was reconstituted in 1947 to become Sansui Electric Co. Ltd, employing about 10 staff, all of whom were involved in producing and selling transformers, chokes and coils. The product range expanded further into other parts by the early 1950’s and the production of kits and finished audio components – monophonic amplifiers and preamplifiers – began for the home market in 1954, by which time the company had expanded ten-fold.

The AU-111 integrated amplifier (that Martin mentions above) - Sansui’s first milestone product – which is still perhaps it’s most sought after – was offered to customers in 1965. The AU-111 integrated amplifier used 6L6 GC valves in push-pull to give 40 watts per channel. This was the first of the company’s products to have the black fascia that became its hallmark and was the one to establish the brand as a force in the high quality audio market.

MartinT
30-06-2011, 08:06
The one thing that bothers me is the minimum length of interconects that are available commercially.
I am going to get a quote from John to make me a special 2foot set for both the inputs and outputs, this way I can keep the wire length to a minimum between MC and phono amp.

Do you mean you want a unit built with flying leads?

MartinT
30-06-2011, 08:14
That's great additional information, Chris. I must admit that, before I started researching Hashimoto, I had no idea that Sansui had such a venerable lineage and were such transformer specialists. The AU-111 looks very desirable indeed.


The word Sansui is translated as ‘Mountains and Water’ and the company philosophy was reflected in the Sansui style of ink painting which produces landscape designs (mountains and water) to represent the ‘principle of universal transformation’.

Fantastic - what a great way to derive a trading name :)

Mike_New
30-06-2011, 08:23
Do you mean you want a unit built with flying leads?

Hi Martin,
I was not thinking of flying leads, so much as using conventional RCA cables but much shorter ones . Where you have positioned you SUT, requires only about 18" of cable length. The shorter the cable at low signal levels the better the background noise and hum even with low impedence sources such as MCs.
But then I guess I am trying to be a perfectionist, which is not always practical.

Marco
30-06-2011, 08:55
I totally agree with Mike - and my experience to date confirms it.

'Weak' analogue signals from MC cartridges are very 'delicate', and so it doesn't take much to affect their integrity, therefore the shortest interconnect cables possible should be used of the highest quality, to relay the signal from the cartridge to the preamp, especially when SUTs are in the equation. I guess, however, that the most important cables of all are the ones connected to your tonearm or turntable (as they are first in-line with the signal path), which is why I use the superb Oyaide PA-2075-DR. The ultra-low loss Furukawa cable used is specifically designed for the job.

Returning to SUTs, the A23 sits on top of my Croft preamp, with its built-in valve MM phono stage, which with having an external PSU in a separate box, has no transformers inside, and therefore zero emitted hum field. So I use 0.5m cables to connect it to the preamp, although in reality, I could get away with merely a few inches. I use 0.5s, though, as I don't want to cut my cables, and also so that it's more practical when I'm using the A23 in other people's systems.

Ortofon had the right idea originally with the old SPU, by fitting the transformer next to the cartridge inside the headshell, which shows how close it ideally should be! However, the tiny transformers used in those days weren't of the best quality, and so although the idea was very good, the results achieved were not as good as is possible today with the use of a high-quality external SUT.

In general, the bigger MC transformers are, the better, providing that they are of the requisite quality, so although there would have been significant sonic gains by strapping very small transformers directly to the cartridge, and eliminating the need for interconnect cables, this was mostly negated by the relative poor quality of the transformers that could be used for the job.

Therefore, on balance, large high-quality transformers (in a separate box), such as those used in Martin's Hashimoto, connected to the partnering preamp/phono stage with the minimum length of cables, is the best way to go - but make sure that those cables are the best you can afford, as they will likely make more difference to the sound than that of the cables used anywhere else in your system!

I found a quite staggering difference in the performance of my vinyl replay recently when I fitted the solid-silver conductor WBT plugs to my Mark Grant interconnects, which opened up the sound, lowered noise, and revealed inner detailing in recordings like I'd never heard before - therefore it goes back to protecting the integrity of that delicate signal as much as is possible.....

This is especially relevant in your system, Martin, as you have cables not only going from your SUT to your phono stage, but from your Whest to your preamp - all carrying that 'delicate' signal from your cartridge, and so those cables should be as short as possible and of the absolute highest quality.

When I next pop down, I'll let you hear what the Mark Grants do with the silver WBTs, along with the Ultimate mains leads. I think you'll be gob-smacked at their cumulative sonic effect! :eek: :)

Marco.

MartinT
30-06-2011, 09:04
This is especially relevant in your system, Martin, as you have cables not only going from your SUT to your phono stage, but from your Whest to your preamp - all carrying that 'delicate' signal from your cartridge, and so those cables should be as short as possible and of the absolute highest quality.

When I next pop down, I'll let you hear what the Mark Grants do with the silver WBTs, along with the Ultimate mains leads. I think you'll be gob-smacked at their cumulative sonic effect! :eek: :)

Thanks, Marco. I'm happy with the G2000HD from SUT to Whest, but my Whest to preamp run at the moment is Mark's Canare star-quad balanced cable. That's why I'm waiting for a 'balanced G2000HD' with such expectation, as I hope it will outperform the Canare and better match the G2000HD on the other side of the Whest.

Choiraudio
30-06-2011, 14:13
Martin,

Thank you so much for the wonderful review and the time you dedicated to the collection of data. As for any artist or manufacturer, having a customer take the time to share his/her impressions of one's work with his friends in such a positive manner is always rewarding. It has been my belief since the beginning to limit our marketing and advertisements, as this type of review from a paying customer, actually means so much more than any marketing campaign with hype, graphs and huge promises of expected performance.

Every system is different, we would be amiss to think that any component would benefit all systems, but to date (knock on wood) the SUT-H series has proven to be a wonderful match with so many different cartridge/phono-stage combinations.

Enjoy the performance as you rediscover your entire collection, and thank you again for such a wonderful review.

Respectfully,

John
Choir Audio, Inc.

MartinT
30-06-2011, 17:24
John, you are most welcome. I am certainly in rediscovery mode :)

Please could you reply to the couple of enquiries here about HM-7 availability? Are you able to ship raw transformers to those who want to build them into equipment?

Pete
01-07-2011, 23:05
Martin,

Glad it was worth the wait!
I knew would enjoy the H-7 as much as I have.

:)

Pete

MartinT
02-07-2011, 07:14
Thanks, Pete. You pointed me in the right direction. Do you have a photo of your SUT-H7 in situ with your deck?

Pete
02-07-2011, 20:55
Need to do a little dusting....

http://theartofsound.net/forum/picture.php?albumid=75&pictureid=550

http://theartofsound.net/forum/picture.php?albumid=75&pictureid=549

MartinT
02-07-2011, 22:33
Do you get any hum problems with the SUT-H7 situated on your cj preamp?

You need to get rid of those Technics feet and put a set of Isonoes on :)

Pete
04-07-2011, 13:59
I put the xformers on the other side of the psu in the Conrad Johnson (which in this unit the power transformer is enclosed in a steel casing).
Routing of the cables did show a tiny bit of hum depending on where they were situated, but shielding is paramount, and I could easily detect how good the shielding is on various cables by putting them in this application. I have no hum issues with my current configuration.

The table is fairly well isolated and sounds marvelous, that's why I have been skeptical that the isonoes will make much difference in my case, but for the heck of it I will get them because it will bother my subconscious until I do! LOL.

alfie2902
06-07-2011, 15:31
With all the fuss over the last few days! :rolleyes: I've not got around to posting on this thread!

Martin, that's a great review & I'm sure it will please John at Choir Audio! I'd love to hear & compare both Hashimoto HM3 & HM7 Trannies. After having a play around with quite a few SUT's here that were loaned to me, I came to the conclusion that the SUT's quality i.e. core material, winding style etc was at least as important as the impedance matching!

SUT & transformer manufacturers don't make things easy though IMO, as to the way they labal SUTs, some just mention ratio's x20 etc, some use ohms i.e. a 38ohm tap or 2-7 ohm spread to match to your carts internal impedance & some +dB gain :scratch:

So from a +29dB & +23dB gain that equates to about 28x & 14x respectively & would show about 60ohms & 240ohms.

With my SPU which Ortofon recommend it sees >100ohms & forgeting the Kondo KSL Sut set on the 3ohm setting, the best results I've had have been with a pair of Altec Peerless 4722 on the 38ohm tap which according to Altec spec will be x36 showing about 36ohms, but Bob of bobs devices claims the Altecs measure on the 38ohm tap at x28 showing about 60ohms. which leads me to believe this SUT may work very well with my SPU!

MartinT
06-07-2011, 16:18
Hi Alfie

I've had Marco's SPU running on my system and it's a superb cartridge/headshell. I can't remember now whether we only used his SUT - I think we did, which is a shame. I cannot therefore tell you how it sounded through CineMags at +30dB gain / 52 ohms but I guess it would be pretty good.

What I can tell you is that Bob told me he prefers the CineMags over the Altecs. That surprised me. You may, therefore, want to consider the new Blue CineMag 3440AH, which are better specified versions, or even the brand new Blue CineMag 1131, which with +32dB gain may be nigh on perfect for an SPU.

Why not write to Bob? He's very approachable and will give you an honest answer on what would best suit the SPU.

alfie2902
09-07-2011, 13:08
Thanks Martin for the pointer to the newer CineMags, they do look interesting!

Marco's SPU & mine are a little different in their internal impedance & the impedance they like to see. Ortofon claim Marco's needs to see >10ohms mine >100ohms. I tried the A23 SPU specific SUT that Marco uses, & you heard, with my SPU & it didn't sound as good as the A23 103 specific SUT I already owned. The Altec's sound quite a bit better than the A23 103 SUT. I bought the A23 because I prefered it to the CineMags with my 103, so even though I've not tried the CineMags with the SPU from my expieriance it would seem I prefer the Altec's over the CineMags!

A friend has just boxed up a pair of HM-3's which I intend to get a listen to, It would be nice to hear your Hm-7's at some point to though!

MartinT
09-07-2011, 13:13
Good luck with all that testing, Alfie. If you're ever 'darn sarf' then you'd be welcome to come over and hear the HM-7s. I also hope to be up at Scalford next year with my full phono system.

alfie2902
09-07-2011, 13:21
Thanks for the invite Martin! If I plan a trip 'darn sarf' I will PM you to see if we could sort something out, I quite fancy a trip to speedysteve's to hear his 5-way horns, so maybe tie the 2 visits together. Otherwise Scalford is looking good mate! :)