SUT With a Manley Steelhead RC?

Usually the overload margin is inversely related to phono gain. I read the spec sheet too and it’s ambiguous Anyway the real problem is using a 1:20 SUT. in the first place.

@lewm - specs at https://www.manley.com/hifi/mshlr  However, there are two numbers listed 50 mV and 93 mV at various dB levels - the 50 mV likely at the lower 50 dB gain.

rdk, where did you get the 50mV spec for phono overload? Since the Steelhead has both MC and MM inputs, and since MM inputs generally tolerate much higher signal voltages than MC inputs, there ought to be two different specs for phono overload, one for MC inputs and one for MM. The output from any SUT ought to be connected to MM inputs, and the gain set for the minimum 50db.

By the way , using a 0.5mV cartridge with a SUT that has a 1:20 gain factor into an MM stage that provides 50db gain is way overkill so far as total phono gain. Most MM stages proved 38 to 45db gain, typically 40db. 1:10 ought to be more than sufficient, with that cartridge into the Steelhead’s MM stage.

I've been demo'd through Tube Rolling the 50's CCa and the 60's Holy Grail, along side same Brand and other Brands Tubes through to the 80's Production.

All Tubes were above Factory Spec, with each Pair being almost identical in their Test Readings. 

There are a few Brands from the 60's that have equal impression with a slight difference to the end sonic.

The CCa and Holy Grails are very Similar, extended periods of time used for comparison might reveal a little more than I detected. 

As a result of the cost required to purchase at the time of my acquiring Vintage Valves, I got a very respectable matched pair of Holy Grails, via two different suppliers at a steal.

I also to date, have acquired a non Siemens Brand from early 60's Production as well, both flavours were seen as equal in value. 

Per the specs of the Manley Steelhead, the maximum rated input voltage is 50 mV. Your MSL cartridge with a 0.5 mV output is stepped up to 10 mV with the 1:20 MSL SUT. Maximum cartridge output voltage can be as high as ten-times the cartridge’s rated output when playing LPs. Therefore, your MM phono stage should have an overload capability of at least 100-mV for the 0.5-mV cartridge. I looked at the specs for an Audio Research Ref 2SE, the maximum rated input voltage is 250 mV and I used higher turns ratio (1:26) SUT’s with 0.4 mV output cartridges and never had any issues. I think most phonostages have a higher max input voltage capability than 50 mV. Also, I didn’t see a single Steelhead user in this thread indicate that they use(d) an SUT. I would poll the Steelhead users to see if they use SUT’s, and if so, the turns ratio and output voltage of the cartridge. This also seems like an appropriate question for Manley. In the meantime if you can get hold of a lower rated MC < 0.24 mV, and see if the issue persists.

I’m by no means an expert on this subject, but all this is based on what I’ve read from a Steelhead owner that was using a Cotter Mk2L (1:70 ratio) with a 0.28 mV output cartridge and was having similar issues as well as my own experience with SUT’s.

The biggest improvement I made in my Steelhead (and it was huge) was swapping out the original tubes to Siemens CCA grey plates and Bendix 6900s. Granted, the Bendixes are hard to find these days (also sold as Mu, I believe), but those changes eliminated any tiny bit of grain I might have perceived in the stock Steelhead. And the gain of the Steelhead is phenomenal. 

In all cases, at all settings, my Steelhead is very quiet.  So (Snackey), I am wondering whence comes the noise you say was bothersome when you set gain at 65db via the MM inputs. Try reducing the gain setting in 5-db increments until you get to a point where noise is not a problem but gain is still sufficient. Was the volume control over past the 12 o'clock position?  If so, that might suggest you won't have luck reducing the gain setting, as I just suggested. I cannot recall ever having the volume control past 1 o'clock, even with very low output cartridges, but that speaks to the input sensitivity of my amplifiers.  Also, try listening to a variety of LPs, to be sure that the noise you heard did not emanate from a dirty or particularly noisy LP. Before this turns into a SUT symposium. If you do hear noise, listen to determine whether it is in both channels or just one.  If in one channel, that might indicate a faulty tube,

I’ve a Steelhead RC that has been the one constant in my system for several years. I ran it as a preamp for a little while but prefer it into an active preamp. I use the Veloce Litho battery pre that has been mentioned in this thread and also have the Saetta battery monoblocks.

A while back I was using a lomc, an Audio Tekne MC 6310 rated 0.1mv. I had the matching Audio Tekne SUT. The Steelhead has tons of gain even on the MM. I could run the 0.1mv Audio Tekne through the MM input and felt it sounded better than using it with the matching SUT. However I configured the ground arrangement there was always just a tiny amount of low level hum with the sut in circuit. It’s possible that it would have been inaudible but for the battery powered Veloce but I didn’t have another linestage on hand to try it.

Anyway, I think with a unit like the Steelhead there wasn’t anything to be gained using the SUT (‘scuse the pun).

By the way, I stupidly sold the Audio Tekne to “move up” to a Benz LP-S. What a mistake that was. The Audio Tekne is still the best cart I’ve owned in my system.

Rooze

ps - love the two YouTube vids someone posted above, one is of my old system before changing out the speakers.

I think it’s well known Koetsu never wound their own SUT’s, but sourced them from a Japanese maker - the question is "who"? Haven’t seen an answer on that, yet. The new metal-box SUT shows some additional components inside there too (resistors) along with damping materials - so they’re probably doing something to "optimize" sonics for Koetsu. The old wood box SUT’s are different - and they lean towards the "detailed / fast" side of the sonic spectrum, with a little extra energy in treble and without destroying the midrange romance (like Lundahls do). It is a VERY good match for Koetsu carts. Can sound great with other carts too, but you have to watch that treble getting too hot. I don’t know how the metal boxes ones sound. 

For Ortofon - their Verto shows Lundhals inside. Pretty much any transformer with that distinct flat rectangular metal box is going to be a Lundahl. Lots of component manufacturers use them (line inputs too). I’d be surprised if Ortofon wound any of their modern SUT’s. I’d be surprised if ANY cartridge manufacturer did.

EAR is impressive for winding their own transformers (and their MC-3 / MC-4 SUT’s are superb), but they’re a component maker, not a cartridge maker.

A quick search on the net resulted in this. "Sugano Jr. resumed the production of the acclaimed Koetsu step-up transformer due to repeated requests from customers. If you hear it matched with the Koetsu range of cartridges, it is easy to understand why there was so much demand for this hand-made supremely crafted transformer".

I am quite sure that some other company makes or made the Koetsu SUT for Koetsu, and then slapped the Koetsu name on the product.  Just like the Koetsu tonearm was made for them by Jelco. Audio Note (Japan or UK) is a fairly wide ranging enterprise (cartridges, preamplifiers, amplifiers, etc), so i am willing to believe they make AN SUTs. My short list of Denon and Ortofon was by no means meant to be complete.

We also have Koetsu cartridges and their own SUTs. Also Audio Note Japan and their IO-m cartridge and their own SFz SUT. There are other cartridge manufacturers that make or have made SUTs for their own brand. 

Maybe because designing and especially building a SUT is a vastly different enterprise from designing and building an MC cartridge for a small company like MSL. You’ll notice that among cartridge makers only the big guys also make SUTs, like Denon and Ortofon, and even Ortofon only makes SUTs specifically for its own cartridges.

I just can’t think that with the MSL Signature Platinum cartridge one of the top performing cartridges would be their own MSL SUT. Many others should work but how can a company that makes some of the world’s best cartridges not design a great matching SUT.

snackeyp, it’s all about what works for you. Keep trying, you will find something you like.

IME, loading is all about gain.

I don't worry about it too much.  Low output low impedance.  High output, high impedance.  That's about it.

It's one detail I don't sweat.

The only reason to put a SUT on a Steelhead, IMO is to bypass whatever Manley is using in the gain stage.  Might be more quiet, might not.  Just me, but if the MM side is not black, that's not a good sign.

YMMV

@car123 Per your suggestion, last night I connected the TT to the MM input of the Steelhead and maxed the gain.  At first I kind of liked it, because there was excitement in the sound, but after awhile I couldn't listen anymore and switched it back. to the MC input.  The noise floor seemed much higher in MM.  After I switched it back I thought I should have tried backing off the gain to see how it sounds, so maybe I will try that soon.  Your suggestion had been mentioned to me previously when I first bought the Manley, so I know it has merit.  I just wasn't happy with the first attempt.  I appreciate your help

@lewm No insult taken. My post about 10x sounded somewhat absolute so that was fair ground. We’re good.

Sometimes it's a matter of semantics, but many do speak of SUTs as if they have an impedance of their own.  This is not the case, so I am sensitized to that implication.  As I know you know, any transformer merely converts current to voltage (if you think primary to secondary), and the impedance seen by the cartridge is simply a function of the impedance present on the secondaries.  The SUT adds no impedance. (This is in a perfect world; in reality there is a tiny effect that can be disregarded for loading a cartridge.)  It's obvious that you have a handle on it, so I apologize for my pedantry in correcting your original statement. I just know some others might have been led astray and was trying to prevent that.

For one thing, if you have a cartridge with a high-ish internal resistance, like a Denon or some Benz cartridges, such that it is not an easy match for a SUT, there is no reason you can't replace the 47K resistor at the MM input with a 100K resistor or even higher, to make the cartridge happy with the final impedance it has to drive.

@lewm- two comments. First, I agree that there is no absolute in matching numbers -impedance of cartridge to primary or input of SUT. I’ve experimented in each case, both on the Allnic and on the outboard unit I use in my vintage system.

Your observation that the SUT does not present a load is intriguing to me. My goal in the above statement was to demystify some of this stuff and simplify it, so it didn’t seem like a dark art. Thus, I used the terminology with a nod toward you.

I do often refer to the setting of the primary or input as the "load" the cartridge sees. I’m also reminded of the occasions where people talk about "loading down" a cartridge as opposed to running it wide open, i.e. 47kOhms.

Thus, this explanation (from a site called "hi fi for lo-lifes"-a moniker that amuses me), speaks in just such terms:

"These passive windings have ratios. These ratios operate as approximations to specify a SUT for matching with specific cartridge impedances. Standard ratios tend to be 1:20 or 1:10 (this is the “gain” usually translated to dB) but numerous ratios exist for differing cartridge specifications, and many SUTs feature multiple winding ratios to add flexibility for different carts (a 1:20 SUT may also include a setting for 1:40 windings). A general rule for MC carts is they prefer a load impedance of 3~6 times their output impedance (for example, a 20-Ohm output impedance cartridge would work well with 60~120 Ohms of input impedance). A 1:10 winding ratio means that the secondary winding has 10 times the number of turns of the primary winding, so the voltage for the secondary is roughly 10 times that of the primary. But, that’s not all the magic the transformer is performing, it is changing the resistive load the cartridge “sees” by squaring the turns ratio divided into 47,000 Ohms (this is the impedance). This translates to the cartridge “seeing” a load impedance of 470 Ohms instead of 47,000 Ohms, a number most MC carts are quite happy with."

I’m comfortable with that explanation. Tell me where I’ve gone astray- not to argue, but to inform. Ty.

When I look at SUTs / cartridge pairings, I first consider "are SUT’s good for this cartridge?". For that, you look at the ratio of a cartridge’s output voltage over its coil ohms. This is proportional to how much current the cartridge can supply (in theory). Since a SUT essentially converts current to voltage gain, this is a good indicator of its match to both a SUT, AND to current injection stages (SUT is passive and current injection is active). Of course there’s more to it than that, but this is a good rule of thumb IMO.

To keep nice integer (rounded) numbers, express the output in micro-volts uV. For for example, Koetsu lists 0.3mV = 300uV for 5 ohm coils. That’s a ratio of 300 / 5 = 60. That’s a "very good" ratio for a SUT. Koetsus yield very strong output levels for relatively small coils, and are a known good match to SUT’s.

Benz iron cross models are not quite as efficient, but they still yield 400 uV / 12 ohms = 33. That’s still a good ratio for SUT’s.

Benz ruby core models suck with SUT’s. They have 380 uV / 40 ohms = 9.5
Van den Hul Colibri is another tough one, with very similar specs to the Benz ruby. But again, their lower models’ generators (Crimson, Frog) are more efficient and work great with either SUT or current injection. Why do some cartridge motors have so much less efficiency? Because they’re either doing something weird with the magnet (Colibri positions its coils in a monopole layout rather than the typical dipole) or they’ve made a choice for the coil’s core to be a non-magnetic (or less magnetic) material than the usual iron / permendur. Ruby, air, polymer (IIRC Ortofon said they use these in Anna?) - these all sacrifice output efficiency in order to reduce magnetic flux disruptions during playback conditions (essentially they are reducing the magnetic complexity).

Most LOMC’s will have a ratio somewhere between the Benz iron-cross and Koetsu. A few have ratios even higher than Koetsu: Ortofon Cadenza Red / Blue / Bronze and all My Sonic Labs cartridges (by a LOT there!).

So once you know a cartridge is "good" for a SUT, then what you want to do is match step-up ratio so that the resulting "MM level" is around 5mV. Now I like to go even higher to de-emphasize the MM stage’s noise floor, but at some point you do risk MM stage overload. With tube MM stages though (generally good overload margins), I’ve found anything ~ 10mV and below is perfectly fine. If you’re falling below 4mV then sometimes dynamics and "punch" can suffer. So just match step-up ratio and never worry about loading - if you have a good cart for SUT and a 47K ohm MM input impedance, it always works itself out fine :) I’ve also never found any value in additional loading on the SUT’s primary or secondary.

The SUT doesn’t present a load. The load seen by the cartridge is dependent on that 47K resistor in the phono stage and the square of the turns ratio of the SUT. There is absolutely no reason to believe that you have to fine-tune the turns ratio of the SUT in order to end up with an exact tenfold ratio between the cartridge internal resistance and the input impedance as seen through the SUT. Any ratio greater or equal to 10 works fine. And I would say you can go below 10 as well. Play it by ear.

I don't think it is a dark art. @lewm will correct me if my terminology is wrong, but look up the internal impedance of the cartridge. You need the SUT to present it with a load that is 10X that number. They all "output" at 47k, which is standard MM input. That's the "step up" part.

For example, I had a couple Airtights, very low impedance and set my transformers to the closest setting of 10x their impedance. When I switched to Koetsu stones, I found a slightly higher impedance worked best. Some SUT set ups are more adjustable than others and SS stuff can be tweaked with changes in resistors or boards. (I use tubes for the phono, but the unit, an Allnic, is  adjustable with knobs on the transformers). I have an outboard SUT in my vintage system. Not a terribly expensive unit either and it's good, runs at a setting to match a Franken 103 with a MR stylus and potted into a wooden body by Steve Leung. 

The transformers themselves get attention too. There are some highly regarded older transformers- collectible, and modern high end ones like Slagle produces. 

Matching a cartridge to an SUT is a black art for me I would reply on other opinions. With that being said I'd also be one to go with a manufacturer of a particular cartridge say Koetsu and then buy a Koetsu SUT. Or if using an Audio Note Japan cartridge then I'd opt for their own SUT. Same with MSL. Would it not be safe to assume these manufacturers know what works best with their own products?

@lewm Thanks for this.  I don't understand all of this fluently, but I'm getting there.  Your help is appreciated.

Cheers

Dear Snackey, Your response, "Matching the gain setting on the SUT or preamp with cartridge output rating.", is not quite the way to think about it.  The cartridge has a certain signal output, expressed in mV in relation to stylus velocity. The standard stylus velocity is either 3.54cm/sec for older cartridges or 5cm/sec for modern cartridges. So that number in mV is the output at that velocity and is just a guideline for thinking about phono gain.  Since the typical MM cartridge makes about 5mV at standard velocity, and since a SUT is connected to MM inputs, the paradigm is to choose a SUT with a step-up ratio equal to whatever it would take to raise the voltage output to about 5mV (give or take).  So you need to know the turns ratio of the SUT.  The limiting factor is the effect that the SUT has on the impedance seen by the cartridge.  The input impedance of the phono stage is reduced by the square of the turns ratio.  So for a SUT with a 1:10 turns ratio, placing it between the MM inputs and the cartridge output will reduce the impedance of the phono stage as seen by the cartridge by a factor of 100, etc. The convention is that the phono input impedance ought best to be about 10X higher than the internal R of the cartridge for best signal transfer (although there is no danger in using a lower ratio, but as you go below 10X, there is loss of cartridge output to ground and possible high frequency roll off due to capacitance).  So, in choosing a SUT you want to have enough boost to result in a about a 5mV output at the MM phono inputs without violating that 10X rule of thumb.  But with a high gain MC phono stage or with an outboard active voltage booster stage (see Hagerman Piccolo for example), you don't have to think about any of that.  You just need enough total gain ahead of the amplifier to drive the amplifier. (Typically, that requires about 1V more or less.) There is no need to worry about "matching". To make this more confusing, most SUTs are labelled for the internal R of the cartridge that works best, e.g., a "3 ohm" SUT is intended for LOMCs with a very low internal resistance but it doesn't have to be exactly 3 ohms.  A 40 ohm SUT is for those LOMCs with a rather high internal resistance (Denon typically), but it doesn't have to be exactly 40 ohms. You need to do some digging to discover the turns ratio of such SUTs. What I am trying to get across is that a SUT is just a tool, not necessarily an embellishment to SQ.

Good question don't recall will ask and get back to let you know.

@rsf507 Thanks for responding.  What phono preamp was feeding into with the MSL SUT?

I've had the pleasure of hearing the MSL Gold into the MSL SUT just sublime whether it was a perfect match wouldn't know made me forget anything else.

@lewm Matching the gain setting on the SUT or preamp with cartridge output rating.  It sounds very different when changing the settings.  Sometimes if too much gain is added the sound it harsh and unrefined.  When not enough gain is added the music sounds flat and lacks energy.  In essence, matching the gain to the output of the cart.  What I've heard is that the MSL SUT is made specifically for their cartridges.  Whether this results in optimal performance or not is what makes me consider buying one.  Cheers

Snackey, what do you mean by “optimize the gain”?

I've had a steelhead for very many years and find it delightful.  My recommendation is that you run your mc through the mm input and max the gain.  It sounds much better than the mc input.

@lewm Yes, I had heard that this is an option.  I might try it.

Honestly, the gain is not the issue through the MC input.  I have plenty.  And I honestly have zero complaints with the sound of the Steelhead in general.  

Just curious if the MSL SUT would optimize the gain for the cart.  I guess the only way to know would be to buy one and try it.  I tried to buy one when I was in Japan last fall but every store that had a display model would not sell it to me, saying I would have to special order one.  I was only there for two weeks so that was really not going to work.  Now they seem to be available again, but I don't feel as motivated as I was then.  Ho hum...

Snackey, I don’t recall whether I mentioned this before, but you can have up to 65db of gain via the MM inputs, which bypass the autoformers. You might try that if you haven’t done it already, before resorting to a SUT.

@billstevenson Thanks for your kind offer to lend me your Bob's Devices SUT.  I will let you know if I want to take you up on the offer.

Nope Lamm did not make it lean, just the opposite- put more meat on the bones, though the frequency extremes were rolled off compared to the Veloce (line stage comparison). As to lacking gain, perhaps that was an issue. It was a couple of iterations ago- sonic memory is imperfect, just remember the processes I went through. The mod you did seems to make sense. I did go back to that Six Moons review- it was apparently edited after the grounding issue was sorted and some newer material added. It's been a while. 

..."the unit sounded a little spare, lean..."  In my experience, that sonic character is very often associated with marginal phono gain, and when higher gain is provided, the coloration is ameliorated. But if you are saying it sounded lean even after you inserted the Lamm, then all bets are off, except maybe you were hearing the Lamm, which after all is another device in the pathway that could potentially introduce its own sonic character.  On the other hand, I am in no way saying the Steelhead is flawless.  However, it sounds a whole lot better post-modification.  I am now thinking of upgrading the attenuator, but I hate to give up the luxury of the remote volume control.

@lewm- Yes, the Veloce unit I own is a line stage and it replaced the Lamm at the time.

I do remember the tweak/mod you described from an earlier thread here but your saved summary is helpful. I don't know the internal differences or running changes in the Steelhead.

Never had a gain issue as far as I could discern-- to me at the time, the unit sounded a little spare, lean. I remember when Six Moons reviewed the Steelhead and the writer had a grounding issue. I wrote to them at the time (dunno if the comments are still attached to the review) about how to solve it. Did have a discussion with Eva at around the same time-- she believed "less was more" by not having the additional electronics. I think it is all system interdependent. As I recall, I was running the Lamm ML2 SETs which are still my main system amplifiers. It was around this time -2013?- that Alan Sircom came to visit; we had some lovely bone in rib-eye steaks that I grilled and a few hours of listening. Alan did a nice write up in HiFi+ at the time. 

I still don't know what is a Veloce in terms of audio functionality.  If it uses 6H30, I assume it is a linestage which you used to replace the Lamm. Yes? I have a strong bias against the utility of spending huge bucks (like $22K and up for Lamm) on a linestage, but that's just me.

I found a blurb I once wrote about upgrading the Manley Steelhead v2.0.  I saved it on my computer, because so many people asked me about it, and I got tired of re-writing the idea for each inquiry. I don't know whether earlier versions of the Steelhead are built the same way or whether the Chinook is also comparable.  But here you go:

"I could not get a schematic; Manley does not provide a schematic even for professional repair shops. But if you read an interview with Evanna Manley, several years ago in 6 Moons, she describes the output stage.  I won't reiterate her summary (please google it; look for the Steelhead review in 6Moons) but suffice to say that the output of the phono stage, which either drives the volume control if you use it as a full preamplifier or the outboard linestage, if you use it as a phono stage only, uses a 47-ohm resistor in series with the signal followed by a 30uF output coupling capacitor, which in my opinion is mediocre in quality, at best.  This capacitor and what follows are holding back the performance of the Steelhead, IMO.  I removed the 47-ohm resistor entirely; it's not needed, and I replaced the  30uF coupling cap with a much higher quality 10uF capacitor. (Choose whatever you like but spend the $$$ for a very good one.)  You need 10uF, I guesstimate, because the volume control seems to have a 5K ohm input impedance (very low).  (10uF driving a 5K ohm load will give you a very low bass cut-off; 30uF is way overkill.) If used as a full function preamplifier, the output capacitor drives the attenuator as noted, and the attenuator drives the linestage. The linestage itself is nothing but a White cathode follower; it adds no gain to the signal from the phono section, but it provides a very low impedance output to drive any amplifier. The output from the linestage section (after its White cathode follower) uses yet another 47 ohm resistor in series with yet another 30uF capacitor of the same type and brand. That connects to the linestage output jacks. I removed that 47R resistor and replaced THAT capacitor with a 4uF film cap that I like very much.  Since my amplifier has a 50K input impedance, 4uF is more than adequate to get good bass. Those two coupling capacitors, from phono stage output to attenuator and from attenuator to linestage output have everything to do with the SQ of the Steelhead. There is a lot of room inside the chassis to use just about any film capacitor you might want, but I would recommend the 10uF Dynamicap E (for “Electronic”) for the output of the phono section that drives the attenuator, and for example a 4uF Dynamicap E for the output of the linestage. Dynamicaps can be purchased from Michael Percy. Other choices are up to you."

Big difference to ditch the two OEM 30uF capacitors and those 47-ohm resistors. Manley chose those odd values, and the odd idea to insert that resistor at all, apparently to enable the Steelhead to drive high capacitance cables, like VERY high capacitance cables, like higher than I could ever imagine anyone using in the home. It's no wonder to me that some owners prefer to use the unit as a phono only stage; that at least gets one of those two (mediocre is a diplomatic choice of adjective IMO) 30uF capacitors out of the way of the signal. It's actually a wonder that the thing sounds as good as it does.

Whart, If you heard an improvement after adding the Lamm, it could be because the Lamm Reference linestage adds about 9db of gain.  Could be your phono gain (60 or 65db in the original Steelhead?) was a bit marginal for those very low output cartridges you were using. Just guessing.

The Link has Veloce and Manley Steelhead as part of the Demo'. 

Well the ’Veloce’ got my attention, I’m listening to the link as I write.

I have just read a sellers assessment of the monoblocks on offer for $4K.

These were $18K New Purchase and are described as trouncing $30K Power Amp’s.

At the used price, this is quite a stimulating offer.

@lewm- I love older Alfas- tried to buy the Duetto, 69 or earlier, in Italy to run the Targa Florio back in the day but prices there were higher than the US and there were few specimens for sale (the idea being I'd save on the cost of shipping a car both ways, and ship the car back to the States afterwards). Wound up renting an old dog for the event.

Veloce was a company that built battery powered electronics for a spell from the fertile mind of  Vytas Viesulas; it is no longer made. It combines what I would call aeronautics grade construction with old school (tube) design. This is the later version that uses the 6h30 and likes the old DR Reflector tube far better than the modern production. 

Here's what mine looks like with the hood under acrylic:

Whart, what’s a Veloce? I own a 59 Alfa Romeo Giulietta Spider Veloce, but it only plays music on an open country road with top down. Later today I’ll dig up my recipe for upgrading the Steelhead and post it here. Also, I own v2.0 with remote. I think it’s a bit different from the original that you owned.

I happen to have a Bob's Devices 10x SUT sitting here gathering dust.  I am not inclined to sell it, but I would be happy to let you borrow it to try.  You would still need to buy another set of phono cables and they should be a match to the ones you already use.  Send me a note if you want me to send the SUT to you.

In relation to the MSL SUT, there is a particular Tonal Quality Japanese Audio Enthusiasts seemingly lean towards, which is for the Rich Tone.

The MSL SUT may? be voiced to create the perception of rich tone is increased to compensate for the Cart' user that desires for more of  Rich Tone than the Cart' is able to produce in a typical MC Input.

I like @mulveling  have quite a few SUT experiences behind us, and even though we lean towards different sides of the Rich/Lean Scale, we both know SUT's can be perceived as unbearably overblown in the Lower Frequencies, to being perceived as Lean in the Upper Frequencies.

What really matters is where the individual chooses to hit the stop button and get of the Bus on the Rich/Lean Route.

I had a Steelhead before they offered remote control but after the first batch. I rolled the tubes on the audio path, using NOS Tele, Siemens and old Raytheons for the 7044. I could never get it to gel in my system, especially using the MC autoformers. I ran it wide open, at that time using a Lyra Titan I (which I think was their best then) and the original Airtight PC-1 (later upgrade to a Supreme). I added a line stage- Lamm L2 Reference, then a Veloce (which is up to date as of this writing) and eventually migrated to an entirely different room, with a number of small changes. I also changed phono stages.

One of the things I found in listening was a slight electronic glaze from the Steelhead which was a constraint to more natural, flowing analog sound. I think every person has their own biases, and their choices-assuming no price constraint- are limited by what they have heard.

The Steelhead in my estimation sounded better with a line stage than using its passive volume control. Thing is really well built, quite flexible, and Eva is a saint. 

in my opinion, this is an idea, for sure, but not what you would call a good idea. If you just want to know what a step up transformer can do for you, sure, go ahead and try it. But if you expect a SUT to change the sonic character of the steelhead in some particular way, perhaps it would help if you would say what it is you want to change. As someone else noted, the steelhead on its MC inputs already uses autoformers, but from what I can tell, and Manleyare fairly mysterious about this, the autoformers are not used purely for gain, as in the case of using a SUT. I say this because you can dial gain up to 65 db using the MM inputs which bypasses the autoformers entirely. And that is what you would have to do with an external SUT. Connect it to the MM inputs, and set gain to the minimum of 50 db. it doesn’t make any sense to me, but if you want to do it, you will not be hurting anything except your pocketbook. If you want to tweak the Steelhead, upgrade the output coupling capacitors, which are mediocre at best. And way higher in value than necessary. My next thought, not yet done, is to upgrade the attenuator. ( I use mine as a full function preamp.)

@mulveling Thanks for your reply.  If I do buy an SUT it will probably be the MSL model, since it's made for their cartridges.  I've spent less money that that on a very good phono preamp so it's hard to justify, but it's an itch I've had for a long time.  I also have to buy a good RCA phono cable to link everything up.  It sounds like I'm trying to talk myself out of this, eh?  

@artemus_5 I can see what you mean, which is actually why I asked the question, but I'm always interested in squeezing out more performance from my analog setup.  I have never tried a SUT, and have heard many good things about them in reviews I've read.  Art Dudley often wrote lovingly about his experiences, and I respected his opinions in general.  I'm baffled by the fact that when I asked three of my local high end audio shops about SUTs that they had no idea what I was talking about!  However, when I lived in Japan I learned that many users of high end rigs swear by them.  

It’s a complicated question, because the steelhead’s "Z" inputs uses autoformers (primary only) rather than a traditional SUT (primary + secondary windings). I don’t think most of us have a good understanding of autoformers in this application lol. I’m not even sure anyone else is using them here.

The description on Manley’s site is fairly good but still kinda hard to parse out. It sounds (perhaps) a bit more like a "current injection" head-amp in electrical function, versus a traditional SUT - where the "optimal" level Manley speaks of is going to be loading the cartridge pretty heavily (and that’s OK).

The "rough" gain range listed of 3 - 12dB is much lower than most head-amps and SUTs, but the extremely high "base" Steelhead gain (up to 65dB) covers for that.

If you get a SUT - it’s going to sound different than the autoformers, that’s for sure. Even SUTs can sound wildly different to each other! All you can do is try a SUT and decide which you like better. If you do, the SUT should be run at the lowest gain level (50dB) on the R input set to 47K and minimal capacitance load (0 is fine). Even 50dB is quite high, so you don’t want to push past the usually recommended SUT gain ratio for your cartridge. For an MSL Platinum at 0.5mV, I think a 10x SUT would be perfect here.

The "Sky" SUT Bob sells is excellent, and in your shoes - yeah I’d give it a shot against the Manley’s autoformers. The "Sky" has a warm, vibrant, rich sound with superb dynamics and big bass response. It’s not as refined or nimble as some of the other top tier SUTs (more expensive), but it’s a fun listen. Fantastic for rock. It really reminds me of a classic tube amp’s sonic style. And it absolutely clobbers the cheaper SUTs (entry level Lundahls, CineMag 3440A) IMO. My main complaint is the little metal boxes can be microphonic and they're also easily bullied around by stiff cables (both solve-able, but a PITA).

I've never understood why one would put and SUT in a phono stage which already has a lot of gain, unless you just want it louder.