Step Up Transformer

I’m thinking of inserting a SUT into my system, and at this point the SKY20 from Bobs Devices seems to have it. Does anyone have experience with this SUT? It will be connected to Cadenza Black and either a McIntosh C70 or a PS Audio Stellar.


I am using Hand Wound Cinemag 1254 Tranx' in my SUT.

At the time of purchase the leader of a Group Buy had made it known as a result of COVID and the manufacturer only running a very small production schedule, these 1254's are to be Hand Wound by the renowned Tranx designer at Cinemag.

A 1254 is quite similar to a Tranx selected by Bob's Devices.

My 1254 has superseded other owned SUT's, of which I retain one other model being the Hashimoto.

The 1254 makes itself known when used in my system, it is happy to get out of the chair and be seen, where as the Hashimoto is much more polite and remains seated. 

Never used or heard a ’Bob’s’

I love my Vintage McIntosh’s MM Phono sound, thus only needed to boost a low MC signal up to MM signal strength, to continue to use the mx110z’s tube phono.

AND, I wanted PASS, to simply send (Pass) a MM cartridge’s output out with zero involvement of the transformer.

Like many of us, you might end up with a small handful of cartridges, or, which cartridge is next after the current one wears out?

I chose some flexibility regarding both signal boost (x-factor)

and a few selectable impedances.

I found Fidelity Research, FRT-4. The impedance changes with the x-factor, not independently

this one looks nice and a good price

note: it has selectable inputs for 3 tonearms.

ENTRE ET-100 is somewhat similar (one less x-factor/impedance choice). Also 3 selectable tonearms.

Some SUTs have independent impedance and independent x-factor controls (rear switches, internal jumpers, etc).


Dear @fundsgon  : I can't understand why you ask for a SUT when the Stellar is a great active high gain phono stage and the Cadenza needs no SUT with the STEllar and if you insist for the SUT you will only degrading the Cadenza sensitive cartridge signal.


A SUT can't improve the quality level performance of your Stellar, ONLY can and will does degrades that cartridge signal.


Regards and enjoy the MUSIC NOT DISTORTIONS,


Raul, on paper your argument makes perfect sense. But in practice things might work out differently. In my system I have the possibility to choose between various SUT’s, voltage gain and current gain devices and some cartridges have a clear preference for the use of an SUT in the signal path. Others definitely do not, it all depends.

I realise this is pretty much a useless answer to the OP, were it not for the fact that in my experience Ortofon MC’s tend to have a liking for SUT’s. My SPU’s, A95, Anna and even the old MC7500 all sound at their best with a good SUT. So I wouldn’t be at all surprised if this also goes for the Cadenza Black, which shares many of the basics with these other models. Just give it a try......

I use Ortofon Cart's, I have friends who also use Ortofon Cart's and between us, there is also use SUT's, Head Amp's, as well as the option to use a MC stage biult into a Phon'.

I and others I spend time with do not set limits on how a Signal from a Cart's is being transferred.

I don't focus too much on the Math, I don't get too much stimulus from number crunching. It is the Sound that is being presented and the variants of the sound (different flavours) that can be created that are maintaining an attraction that I find the most stimulating.

On this forum, I believe I once referred to a experience I had, where a demo was taking place with a Ortofon Cart' that was attached to a SME 3009. This set up was was met with posts where the description of the set up was not too well received  and it was challenged as a concept.

'Nobody Died', "Get Over It". If a individual likes the idea of experiencing a SUT with a particular Model of Phonostage, then let that itch be scratched.

The 1254 @pindac  mentions is indeed very similar to the Sky 20. I’ve had both. The Sky might be a bit sweeter but both have that “boogie” factor and lush midrange that I think really benefits the Ortofon MC cartridges (which can otherwise be too dry for my tastes). Either one is a great choice for your cartridge IMO.

edgewear, Wouldn't it be more fair or accurate to say that you are the one who prefers one or the other mode of phono amplification with this or that cartridge?  (Rather than to say that the cartridge prefers a particular sort of voltage gain.) Nothing wrong with that, but we are talking about personal preference, which is always unchallengeable.  Similarly, the OP may prefer a particular SUT vs using his high gain phono stage, and that's OK too, but apart from helping him to choose a "good" one, no one of us can say what particular SUT flavor he will like.

This is just great to hear from all of you. I’m pretty certain that I’ll go with a Bob’s Devices Sky 20, which has a selector switch for 2 gain settings.

For cabling, what would be your recommendations. I’ll keep my existing cables from the table and connect them to the SUT, but what about from the SUT to the phono pre? These will only have to be 18” or less.

All connections are RCA.

Dear @fundsgon  :  Can you explain which are your targets to " introduce " a SUT+cables+input/output connectors and solder joints additionals im that PS Audio phono stage?  is it because you are a MUSIC lover or maybe just for fun?

In the past how many times did you listen an Ortofon Cadenza in an active high gain SS phono stages along SUT's? and know what are you looking for? what do you not like on that Stellar phono unit?


Thank's in advance,


@fundsgon As a person who really enjoys music, I get the bulk of my musical encounters from the Radio/CD used in my Vehicle.

To extend my enjoyment of music and fit into the usual practices within the home and share time in a room in the Company of loved family, who love to make time for musical encounters, much of the musical encounters is supplied through Alexia.

As an individual with a long term interest in audio and having a decent sized collection of Hard Media, I have across many years, put together a dedicated set of devices to enable a decent level of quality for the periods that are spent replaying the Hard Media music collection. All devices used above are merely Tools to enable a experience of a musical encounter. Each has the capability of creating a stimulation that is enjoyable, otherwise why keep revisiting/exposing oneself to the different experiences.

My advice is enjoy your musical encounters, your first attraction to music, as well as one that set you on the journey of discovering audio, was most likely discovered on what could be called a Low Fi Device. Enjoy the experiences of finding out how there are other methods to be used in your audio interest, for you to experience your Hard Media Music Collection.

@lewm sure, everything is a personal call. And I did say 'in my experience', didn't I? In contrast Raul always presents his opinions as the Gospel, so I figured a contrasting opinion wouldn't hurt.

@edgewear Your Statement, "But in practice things might work out differently. In my system I have the possibility to choose between various SUT’s, voltage gain and current gain devices and some cartridges have a clear preference for the use of an SUT in the signal path. Others definitely do not, it all depends.

I realise this is pretty much a useless answer to the OP, were it not for the fact that in my experience Ortofon MC’s tend to have a liking for SUT’s."

I read this as the Cartridges referred to having a Clear preference for a SUT' as being more akin to my own experience.

I can use a Cart's with a few options on how to send the signal generated.

I don't rest with one option only, I know how I like a sonic that is produced, as well as knowing how the devices work with different genres of music and how the sonic produced can impact on my mood at the time.

On a Weekday evening the Hashimoto, has a sonic that can keep me in the chair quite docile.

On the Weekend during an afternoon, the Cinemag, will get Air Guitar / Drumming kicked off with almost a immediacy.

I also have a Built In MC Stage and it presents quite satisfactory, I am keen to use it when I want to have the other benefits it offers when worked with. 

@pindac I recognize the ’flavour of the day’ argument, which is why I ended up with more cartridges than strictly necessary and various tonearm and amplification options. After reaching saturation point with record collecting and satisfaction point with the audio system, the ’hobby’ aspect is now restricted to cart rolling. From personal (okay lewm?) experience I’ve learned that some combinations stand out, sometimes when you least expect it to. The sound has an intrinsic rightness, as if there’s some kind of electric handshake. In my system(s) the Ortofon cartridges I own behave like this every time I connect them to an SUT.

From personal (okay lewm?) experience I’ve learned that some combinations stand out, sometimes when you least expect it to. The sound has an intrinsic rightness, as if there’s some kind of electric handshake. In my system(s) the Ortofon cartridges I own behave like this every time I connect them to an SUT.


Several cartridges, phono stages, tonearms here too (LOTS of headshells and arm wands on hand) -- and what you've written really gels and resonates with my experience! Without a SUT I perceive Ortofons as dry, lean, and lacking passion. With a SUT - they're still not a Koetsu but sometimes really surprise me and "hit the spot". The Windfeld Ti is probably my most "hot and cold" cartridge, but for last session at least, it was very hot!

The Blue Lace on FR64S is my unimpeachable Reference. It's always, consistently great -- so it's not knocked about by the ebb & flow of my transient preferences and moods. The various Benzes, Shelters, Ortofons, and other Koetsus are constantly undulating up & down in rankings (relative to each other) with my affections. There's always ONE of these that makes me think "I like this as much as the Blue Lace!", but it never lasts for long lol.

Did not mean to offend anyone. Just trying to make a point about the subjective nature of these decisions. It seems the OP has chosen a SUT. One hopes he will be happy with it, and even more than that, it will be interesting to learn how he  likes it compared to his high gain phono stage for sound quality with his cartridge. 

Dear @lewm : I think that more and more Agon forum audiophiles ( 90% ) as in other internet audio forums people are fully oriented to what they like and nothing wrong with that .

The experimented audiophiles as edgewear or mulveling and many others targets are what I said here about and we can read and confirm that issue through the posts in this thread and in almost any other threads, even the OP just does not cares of what is recorded in those LP groove modulations and obviously not only him.

I think too that an issue is that today part of our hobby more than enjoy true MUSIC as is recorded or " near " live event: " we are looking for colorations, added colorations, in what we listen day by day.


The SUT is a pristine example as many other added links in our home system chain, I already posted: a SUT can’t improve any recorded LP vs an active high gain phono unit. Everything that we add to the cartridge signal during LP reproduction can’t improve in no single way the quality levels of what we listen with out those " adds ". So we like those added " colorations/distortions " and can be addictive. In the past I was " there " in that same " road " that is part of the fun even if is wrong road.

In my system I try to put at MINIMUM the steps where the analog/digital audio signal must pass through but these is me and what I learned about is that when we put at minimum those signal steps what we experienced through our room/system is reallu outstanding and just near the " best " we can be to MUSIC recordings or live event.

The MUSIC audio road is a learning ladder that we have to go up step by step and no I know I don’t finished yet.


Lewm and dear friends: don't you think that all those recording process steps till we receive the LP are not added enough distortion/coloration  to add other than the minimum necessary steps during the play process?



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Dear @edgewear  : It's no surprice the mistracking you experienced with the 64S and low compliance Anna where its resonance frequency is not aquated and out of the " ideal " frequency range when in the 64FX it's spot on at the middle. The 4400 is almost a unipivoted design with some trouble with its bearing damping oil ranges and with its lateral balance too and not good couple for the Anna and I don't know which pipe arm you used with the 237. Btw, I don't know if you still use the RX-1550.


" The dry and lean character simply vanishes with a good SUT. "


,Well knowing Boulder that's more or less how was recorded those or " that " LP, the Ortofon character and the SUT gave you not better quality level cartridge signal performance but only added the colorations you like it even if those colorations are only added distortions.





@rauliruegas you really know everything don’t you? I know you don’t like FR64S, so no surprise there. But I was very surprised as well as disappointed that Anna even mistracked in the MAX-237 (with J-shape armpipe), because that arm could handle everything or so I thought. I also know you don’t like SUT’s, but why do you think an active gain device wouldn’t add colorations of its own? The Boulder electronics were selected for their neutrality and that’s generally how they present music through the Maggies. With cartridges like Miyabi Standard, Transfiguration Proteus, Shelter Harmony or VdHul Colibri this delivers a sound that to my ears is very accurate, but also enchanting and immersive. With the Ortofons this set up emphasizes their own neutrality (a good thing in itself of course) to the point of being sterile, which keeps you uninvolved. Somehow a good SUT restores that balance. At least that’s the way I perceive things, but of course YMMV.

Rauliruegas, you make some good points. I heard the cadenza black in another system with a sut, so thought to give one a try. How does a SUT degrade the performance; what type of distortion or colour does it introduce.

It is a general consensus, that an Additional Pair of RCA Phono Connector Inputs are used, followed by quite a few metres of Copper Coil and Lead Outs, followed by RCA Connectors as Outputs and then an additional pair of Cables is to be used.

The same above stands for a Head Amp in use as well, but swap out the Copper Coil, for a circuit built with usually seen component types. 

The suggestion is, and mostly presented as a subjective evaluation based on the idea,  increased components in the signal path, deteriorates/adulterates the signal path, and the shortest signal path is working toward the ideal.

I have not seen any measured data, that clearly defines sound produced from a signal passing through a SUT or Head Amp' is an inferior Sound produced at the Speaker End.

Do keep in mind signal that is produced prior to passing through the Speakers Xover, is an electrical current. It is only when the electrical current/signal has travelled as far as the Speaker, is the time it becomes sound and is able to be evaluated by each individual. In most cases individuals do nit share identical attraction for the same produced sound. We are all unique and have sensitivities to how we are affected by sound. 

Dear @edgewear  : The issue is not about FR but what showed your Anna in those both FR tonearms that just said the FX truly was and is spot-on with.

The Anna is not only a " so so " tracker along those 16grs. on its weigth.

I owned the MAX 282 with all its 3 arm pipes and two but the J shapped 237 and I mounted there bad bad trackers to exceptionall trakers/ heavy ones and not so heavy and never had any single trouble with mistracking in any MM/MI/MC over 100 cartridges in cluding Ortofon but not the Anna. The gyroscopib MS tonearm bearing is really a beauty..


About the SUT issue it's not that I'm " against " it per sé and for several years I used SUT's , many to name it here including the best best SUT ever made exclusively to Denon by Murata : Denon AU-1000 that still I own and it's modified by me ( obviously not the transformers. ). Now a " few " years ago and even been owner of the AU-1000 a close friend of mine started and finished a " new " Phonolinepreamp that in those times outperformed in my system FM Acoustics.

We took around 2 years and a half to been finished and I still use in its version 3180, @lewm  own the 3160 version and other gentlemans the 3150.

Why took we the responsability to build that kind of unit?  easy: because no SUT/phono combination and top full SS active high gain units as the mentioned FMA truly even my way demanding analog targets till appeared the 3150. 

All versions came with two totally independent ( including power supply ) dual mono phono active high/low gain stages even time to time I use its MM stage along the AU-1000 and is enjoyable.


Btw, we are thinking to re-start that phonolinepreamp design maybe with 4-5 latest version including one for me. This is in the desk  because is not my business way of life and each unit time to build take a lot of time . We will see.



Dear @edgewear   : " but why do you think an active gain device wouldn’t add colorations of its own?  "


Where posted I that statement?, every device develops some kind of distortion level.A well matched pairs of bipolars is all what the cartridge signal looks at the very first stage in an active design. Its distortion levels are way low and the length/distance that that signal needs to " walk " is really low too. So, if that phono stage is a good design, the signal that goes to the inverse RIAA eq. is almost direct from there to the output. It's only common sense

 In the other side a SUT has a way limited whole frequency range . Any one in this thread knows what is the FR of that Sky 20?: I'm almost sure no one has it.

Today SUT's but one have short FR and nothing even approaching what was measured in my Denon AU-1000: 3hz to 305khz but a vintage FR goes down to 2hz !!!! the best ever and Technics goes from 3hz to 350khz.  The Sky's not even dreams with and I think that the Denon AU-340 that goes from 10hz-100khz is even better that what the OP is looking for.


Btw, the today wide band SUT ( silver wire ) is the intactaudio design.



Ah the endless audiogon churn between those who pursue what should sound good versus those of us who only care what actually sounds good! I seriously don’t care what happens at or above 100kHz. And for vinyl playback, any significant signal below 20Hz becomes rapidly destructive.

Modern SUTs have plenty of bandwidth for high end vinyl playback. If I felt it were lacking up top, then I’d probably like the supertweeters on my Tannoys but I actually hate them.

If extreme bandwidth is the goal, then DSD should be the focus.

Putting the math to one side, it seems to myself, when a SUT is reported as being used/intended to be used, as a Standalone Device to amplify the Current/Signal produced in the Cart's Coils. The idea of using the SUT tranx's built into a Standalone Unit, receives much more discussion about Pro's/Con's or Preferred/Not Preferred, than the similar designed Tranx' types being a component used as a part on a circuit within a Phonostage to produce a MC Input.

I can't recollect seeing any commentary that makes a criticism of a Tranx' used as a component on a circuit within a Phonostage.   

Does this not suggest?, that the Additional RCA Connectors and required additional Pair of Cables are the main focus of the 'anti's' when commenting on SUT Tranx's being used to amplify a current/signal.     

@rauliruegas it's true you didn't say that with so many words, so I stand corrected. But you do keep repeating that a SUT only adds distortion, which seems to imply that the active MC gain device it replaces does not add or at least adds LESS distortion. If you look at the 'dry' specs you're probably right, but doesn't active circuitry add it own set of problems compared to a passive device like a SUT?

I'm not partial to either and use them both as equals. Both are capable of delivering great sound (or as you would say: according to MY set of preferred distorions), but when you choose the wrong combination the whole thing will collapse before your very ears. I've been very critical of Koetsu's sonics when used with several active SS gain devices. Its sound literally transformed using a silver wire SUT. In a less drastic way the Ortofons show the same behaviour. So I think there's more to it than just supposedly 'superior' specs on paper. It seems to me that dismissing SUT's categorically because of 'inferior' specs is a mistake.


@edgewear I visit a few forums, as I do not limit the content of a discussion I have an interest in to one forum only.

It is good for myself, to see where others from another place and set of experiences are commenting on similar subjects that have got my interest.

I can assure you that every forum, that has a dedicated Analogue Section, with a regular contribution from time served experienced members, also has a selection of members who thoroughly enjoy and are advocates of the SUT to amplify a Cart's generated current/signal, especially selecting a SUT for producing THIER preferred Sonic and through experiences encountered are using devices with recognised traits, that are associated with the device of choice.

The Good News is that an individual with an interest in such a method, will find plenty to suggest, their inquisitiveness, will not be wasteful and something that is quite attractive and desired to be maintained can be realised as the outcome.   

For what it’s worth, and that’s probably not much, a SUT increases signal voltage (not “current “), and a SUT decreases signal current in direct proportion to the increase in voltage. The product of voltage X current at the primary is equal to the product of voltage X current at the secondary side. So if V goes up by 10X, then A (current in Amperes) goes down by a like proportion. In this regard, a current driven phono input is the opposite of a SUT.

@lewm Is it this description of a equation, that may be the impact that is detectable/audible/responsible for the SUT, when used to amplify the current/signal, having won over so any advocates for the device to be put into and kept in service?

Dear @edgewear  : I think that the " trouble " culd be that till today maybe you do not experienced listen sessions trhough an excellent designed phonolinepreamp like latest Dartzeel, FMA, CH, Moon and the like. No, Boulder is not in that league is good but not excellent, overall my unit belongs to that league. Till you live that experience you will follow thinking in the same way. No, it's not only about " numbers " but something that even a non-audiopile can dicern easily about and I already posted that I'm not against per sé to SUT's that I not only own but time to time have lisen sessions with , good sessions but the active high gain is superior and I have to say that with the AU-1000 not for a wide margin but superior.



It is looking like the suggestion from one contributor and maybe indirectly others, for the action required to take a Step Forward that is noticeable and a betterment, to using a SUT, if the 'off the shelf' option is considered. Requires that to get the best of the experience without a SUT, monies are needed to be parted with, that can be up to a five figure sum.

The most expensive Commercial Product Phon' I have received a demo' off, is offered with a £10K retail price. This is a Phon' I have been in front of whilst in use on many occasions and it is a Phon' that has thoroughly impressed me. It is also a Phon' I am able to live without, as I have Phon's that are not of this Value, that offer a impression that is just as satisfying.

Bear in mind, both Phon's owned by myself, are very close in their base values to the £10K, when the electronics are being priced. I also believe the designs between the three Phon's are not too distant and there is a shared trait that can be discovered between the Phon's.

Five figure sums are not required to purchase a Phon' that can thoroughly impress.





a c involv 

@edgewear : Btw, you could be one of the future owners of the 3180 that will be custom made due that the owner can choose between unit with 2 MC independent stages or one MC stage and one MM stage. In the MC/MM configuration both independent stages are different at the input gain stage due that in the MM we don’t use bipolar devices as in the dedicated MC but a different active input device dedicated to MM. Any one could has the opportunity to to arrive at a little " different " new " enjoyment world " through the 3180.


Anyway, the main issue is to enjoy MUSIC for any one of us.



This ha been a really good discussion. I was thinking of purchasing a SUT from Bobs Devices, simply because I didn’t know where else to look.

Are there any suggestions for an off the shelf step up transformer, one with wide frequency band and low distortion?


Not sure what you're after. Bobs Devices SUTs are certainly "off the shelf", and if you purchase one of their best SUTs, and one that is suitable to both your cartridge and your phono stage, you will probably have wide bandwidth and low distortion.

Pindac, I am not sure you directed a question at me, but if so, as regards voltage vs current, in the case of a SUT, you are aiming to amplify voltage, not current, so the fact that you lose current in proportion to the voltage gain is of no consequence to the downstream voltage driven phono stage.  The advent of current driven phono stages has muddied the water for some, but you'd never want to use a SUT with a current driven phono stage.

@rauliruegas it seems what you're telling me is that I would need to purchase one of those $25k+ Swiss devices (not sure what Moon is doing in that lineup) to be able to hear the superiority of active gain devices over a passive SUT. This will never happen, so it's a non issue.

But in more practical terms you're effectively saying that at less extreme price levels an SUT is in fact NOT inferior to active gain devices, just a different approach but equally valid. This confirms my own findings and it seems relevant information for folks not into that $$$$$ game. This is not whatsbest forum, so I should think regular music enthousiasts are in the majority here, not millionaires. 

@edgewear  : The Moon is better than hat you could imagine. Anyway, unfortunatelly as me no one else already listen all the phonolinepreamps out there and the " best " out there are not at 25K but over 35K as the Boulder 1110 that I never had the opportunity to listen.

The 1010 is not in that league and I do not want to speak about price but about quality levels design that at the end is what makes the differences. My unit never was on that price levels and never will does but the issue is that is a true challenge for any of the $$$$$ units out there and is a unit where you can discern for sure if any of your SUTs performs as good as the active unit, I'm saying and not posted that the SUT/MM combination performs /" even " my 3180 ( the new unit will be the 3200 ) but a different approach NO I'm talking that the active unit is superior to a SUT connected to a dedicated MM stage in the 3180 and not just any SUT but the modified AU-1000. 

Perhaps what I intent is to say that for a SUT/MM stage combination could really performs at better quality level it needs that that active MM phono stage be a top class dedicated MM design. Normally the phono stages as in Boulder other units the low gain stage for the SUT is the same kind of design for the active high gain stage. I posted that that does not happens in  the 3180/3200 where each phono stage is dedicated to the cartridge needs and in our design that means different active gain input devices.

So maybe for what I posted I left the impression that only the $$$$$ units makes good quality design.

Btw, you are a Boulder oriented gentleman: did you listen the 1110?


@rauliruegas I haven’t heard the 1110, but you do know this is a linestage only? So I don’t see the relevance in the context of this discussion. As for the dedicated phono amp in the 1000/1100 series I have it on good authority that the current 1108 is only a marginally different design than the 1008 that preceded it.

For what it’s worth, the phono stage of the 1010 in MM mode combined with a good SUT can reach the same sound quality level as the 1008 phono amp in MC mode. Provided you hit on a cartridge/SUT combination that meshes really well. There is however a significant sound quality difference between the MC stage if the 1010 preamp and that of the 1008, besides operational differences like limited 60dB gain level (1008 is 70 dB) and the fixed 100 ohms impedance (1008 is adjustable). The Boulder 1000 series components which I’ve owned now for 10 years or more are the end of the amp journey for me. So I have no interest in the newer 1100 series, let alone their higher 2000/2100 series or other ultra $$$$$ stuff, including the brands you named.

However I might still search for a better SUT than Ortofon T-3000, like possibly the Denon you mention or the Audio Technica AT-1000T which is also supposed to be one of the best ever. Just out of curiosity and because it wouldn't require remorgaging the house.

If a search for an alternative SUT does become a interest.

The EAR 'The Head' SUT is one model worth looking into. These are quite rare, but do surface as a sale item occasionally.

A Member of m Local HiFi Group has one, it has been side by side demo'd to a variety of SUT's in a few different systems and has been the model that all attendees have been thoroughly impressed by and unanimously agreed to be something very special. 

I have the EAR Head here - it is ok at best, not the best tranny I have.

Tim told me it was the best he has ever made - exceeds the MC3 & MC4.

@dover given your extensive experience, would you share with us what you consider to be the best trannies you ever heard? Thanks.

Another new option to consider is to use an outboard current driven gain stage to feed a very good MM stage. Sutherland make one, and I’m using one from another source that was custom built for me. Results are excellent if you’re limiting your choice of cartridge to very low output MCs with very low internal impedance. But that’s what you do anyway when you choose to use a SUT.

@lewm yeah, but I was under the impression that most current gain devices have a line level output. I use one such device myself, the Swiss made Blue Systems Aria built by Reto Andreoli. This unit offers an interesting alternative to SUT+MM voltage gain or MC voltage gain amplification. In my experience it provides the best performance with ultra low impedance cartridges, like Transfiguration Orpheus L and Proteus. This should come as no surprise, but perhaps I will hit on some other less obvious combinations that sound much better than expected. These are the surprises that keep the 'hobby' aspect interesting.

Two different things. I think you’re referring to current driven phono stages that supply all the gain needed plus RIAA correction. There is a plethora of those. I’m talking about a current driven external gain-only device that does not supply RIAA or by itself is it capable of driving an amplifier or downstream linestage. It drives an MM phono stage. IOW it’s a head amp or pre preamp that works off signal current not voltage. I only know of one such commercial device, made by Sutherland.

The EAR ' The Head' SUT was made in a small quantity, which results in very small numbers of individuals that have experienced one in use. The idea they very rarely are seen as a used sale item suggests for most owners, these models are keepers.

Whether the SUT is kept for its sonic capabilities or the fact it is appreciating in value is one for the Jury to decide.

For myself, I have come to trust the assessments of my Local HiFi Group, especially with one member being a dealer in High End Audio and another a retired Hi End Audio Dealer, where each have /have had clients that are using six figure sum systems. I think their assessments are with a validity and ones I will not discount. The other members making known similar assessments only reinforce the overall assessment, of the impression 'The Head' has made.

I know a man who has no desire to part with his owned EAR 'The Head', they very much enjoy what it does, and have no doubts about what it does in comparison to a limited number of other SUT's, it has shared demo' time with.

As an alternative, the last one I had seen as a sale item, was with a £2000 asking price, which is a substantial appreciation in Value.

'The Head' is now a Legacy Item  and because TDP is known to be very closely attached to this design, they will most likely appreciate further toward the heavens, where TDP is at rest.

A SUT that I have been demonstrated recently in another System and have put it on my shortlist of Home Demo's 'to be had' when the system is back in use, is a selection of models produced by Sculpture A. I am feeling very good about having discovered this design and it is one of the rare items, I get compelled to want to experience in the home. The individual who supplied these for the demo' I was attending, has made it known, by the time I am ready for a home trial, the Company will have brought further improved New Models to the Market. I look for ward to seeing if these can be brought along to.  


I have a Cinemag 1254 based SUT built by Ned Clayton on eBay.  I find it to sound fantastic, and should be similar to one of Bob's Devices but is much cheaper.  It has 4 gain settings for ultimate flexibility, and 3 ground settings for the most quiet blackest backgrounds you'll ever hear.  I find detail and clarity and bass drive to all been kicked up a notch as opposed to going straight into my phono pre, which is quite hissy at high gain levels.  Now my MC setup is dead quiet, something I'm not used to, and paired with my old Koetsu Black, I am in vinyl nirvana.


@dover given your extensive experience, would you share with us what you consider to be the best trannies you ever heard? Thanks.

That is like asking how long a piece of string could be if you unwound it.

I have not heard any mc transformer that sounds as good as my current mc input 

In terms of best, the problem is that there is no best, it so much depends on the cartridge/sut/phono combination.

For example I have amongst my collection some Altec 4629's and 4722's. Same "specs", different construction. With most cartridges the 4629's outperform the 4722's - however with one exception, with my Garrott rebuilt Denon 103 the 4722's outperform the 4629's. With all my other cartridges the 4629's outperform the 4722's. The 4722's easily beat the Auditorium 23 specifically designed for the Denon 103.

My experience trialling a variety of SUT's with a range of top cartridges with internal impedances ranging from 3-40 ohms I have come to the following conclusions -

None of the SUT's are neutral, none sound the same despite some having similar gain structures, turns ratios etc.

The SUT's all have a unique character that you can hear regardless of the internal impedance of the MC.

I think that trying to match the SUT to a MC in terms of load presented to the cartridge ( the most common methodology promulgated on this forum ) is wrong.

Much more important than loading in my view is getting the gain structure right so you have the optimum voltage going into the phono. Many vintage transformers have too much gain for modern tube mm phonos resulting in the preamp volume pot operating in the very low region where noise and more importantly accurate tracking matching between channels is compromised.

I have never needed more gain than 1:10 turns ratio at most, using my modded Marantz 7 ( phono around 42db ), even with cartridges like my Ikeda Kiwame which is only 0.15mv.

Currently in my cupboard I have SUT's from Altec ( 4629/4722 ), various FR's, Jensen, Tims Head and some vintage Ortofon units. Many others have passed through.

Conclusions thus far ( in my system )

Jensen's - most neutral - important note - I have optimised the Nobel networks for the individual cartridges used, this is required to get the best out of them.

FR's - horrible, compressed, gluggy, flogged them all off apart from one which was a gift, so I can't sell it, never use it though.

Various Denon SUT's - very good bang for your buck, some work exceptionally well. for example with my Dynavector Karat Nova 13D one of the Dynavector engineers advised me to use the vintage Denon AU103 other than the matching Dynavector head amp and/or SUT.

Kondo's - lovely "sound" but dreadfully slow.

Auditorium 23's overrated, optimised Jensens and vintage Altecs are better.

The Head ok, nothing special.

Peerless/Altec 4629 - if I need a SUT I tend to use these, can be configured for different gain structures - midrange is nice,  but lacks bottom end extension and top end not super refined. By the way if you pull one of these vintage grannies to bits you will find individually annealed plates within the laminations - depending on the annealing process you can modify the efficiency and electrical behaviours of the transformer and in those days Jensen had 200 plus engineers fiddling around with each individual process in manufacturing for fun and learning - something no one could afford these days. They also use teflon within the windings. Probably most of ttheir research learnings have been lost. 

Unfortunately whenever I use a SUT in my system the compromises are too much and they don't last long.

I would only see a benefit from using a SUT where the MC gain stage is not very good or you want a "sound". MC transformers have phase shifts and therefore cannot accurately reproduce the fundamentals and harmonics of a note. On the other hand they can help reduce noise due to their passive nature.

Personally I value coherence and timing ( I seem very sensitive to timing and phase errors ) and therefore don't use them.

Having said that decent MC stages are few and far between. 

Also one other recollection - in discussions with a top cartridge designer there is a correlation between cartridge design ( not impedance ) and the attributes of the magnetic circuits within SUT's - for example if I recall correctly they recommended certain SUT's ( toroidal vs conventional core ) with specific cartridges based on the known distortions inherent in the individual cartridge design ( magnets, poles, layout etc ). I don't think anyone here would be ab le to explain this other than maybe Jonathan Carr.

In a word SUTs are a crapshoot. To find the best you have to try them all out on your system with each individual cartridge.. It will cost a fortune, there is no one best.








post script

I also have in the cupboard a much vaunted pure tube mc head amp and a hybrid fet/tube mc head amp that I have modded. The hybrid fet/tube head works very well with the ultra low output Ikeda, very dynamic and very coherent, slightly down on resolution compared to my current input option.