Advice on SUT for Koetsu Rosewood - EAR MC-4, Slagle/EMIA, other

I recently tried a friend's Sound Traditions Hashimoto hm7 transformer-based sut and overall the sound was substantially more Dynamic and alive and generally better than my current Berning preamp MC section. The problem was the images were just so large and the presentation a little too forward for my tastes. I am thinking a different Sut such as the EAR MC- 4 or an Intact Audio (Slagle) Step Up Transformer, copper.

Has anyone used these Sut's and could advise about whether they might do what I'm looking for? I'm hoping to add more dynamics and life but I do prefer a slightly laid-back presentation to a forward one and I don't want giant instruments in the soundstage. I listen to mostly old Jazz and Blues with some rock and classical mixed in. I am not looking for the last word in in treble detail or "air" and my biggest sonic priorities are organic , rich mids, good sounstaging, and a realistic tonal balance that does not accentuate the top end as so many components seem to do (IMHO). So I guess I am looking for a sut with a reputation for musicality and richness, without javing a forward sound. But I would love somethng as amazing sounding as the Hashimoto HM-7 based SUT.

My system is a Koetsu Rosewood Signature (.4mv), Jelco 850M on a Sota Star Sapphire, Berning all-tube bespoke capacitance coupled preamp (46 dB gain on the MM stage, Jensen transformers on the moving coil stage), Quicksilver v4 monos, Verity Audio Pafisals.

Thanks for any thoughts.


Showing 15 responses by mijostyn

Montaldo, I would get two of these,
and wire them directly into your preamp. There is no way you can do better at near the price. These are truly giant killers.

rauliruegas, you do it this way and there are no additional outside connections, cables, etc giving additional fidelity and cost savings. 
You need to tube your life just a little:)

Yes Montaldo, Excuse me. Not sure what happened. Here is the right one.  This is the version that is specifically meant for your cartridge which has an impedance of 5 ohms.
Notice the Bandwidth is higher. I have put these in ARC PH 3s for extremely low output cartridges and the results have been excellent. Any of the great cartridges will work with them, Air Tight, Lyra low output, Ortofon Anna etc. Wiring is simple. Just put a dab of silicone anywhere you have some real estate inside. Press the transformer into it and let it sit over night. You could add a soldering terminal to make the connections but you could also do wire to wire connections covering them with heat shrink tubing which would work just as well. 

You bet montaldo. You would replace the ones you have and you will see that Sowter makes several versions aimed at different cartridge impedance's. The one I suggested is the right one for your Koetsu. It is a simple installation. I have no doubt your tech can do it.  

montaldo, 64 dB gain should be more than enough for the Koetsu. I'm not sure what the problem is. Perhaps it is a loading problem. Is the input impedance adjustable? 100 ohms is perfect for the Koetsu. If you can't adjust it than the Sowter transformers will certainly help. 

rauliruegas, yes, some tube equipment can be a PITA. But some like my ARC phono amp run perfectly without a hitch. In 20 years I replaced the tubes once. IMHO the tube rolling gig is for people who want to become psychotic. 
Montaldo, it looks like you are facing a trial and error situation. Trying to audition all this stuff is virtually impossible. If it is a higher step up ratio you are looking for the Sowter 9990 unit is 1:20 for 1-15 ohms. They cost about $100 and you will need two of them. Not crazy money at all. The risk is that you might overload your phono stage. If so, you could just put a resistor in series with the secondary. But if you have used a 1:20 transformer and there were no problems you should be all set.  I prefer the transformer be internal. I think there is less noise and you don't have to mess with interconnects and two more connections in line.
Ralph, you would think the transformers would be designed for a 47K load which is pretty standard for MM phono stages. If not 47K how would you figure out what it was? Just a meter? Also why the capacitor. Wouldn't just a resistor do? I know you might have to change capacitive
loading for a MM cartridge but why the transformer?


Ralph, Sowter offers different step up ratios and tells you what cartridge impedance range the transformers were designed for. Is that enough in and of itself to get you headed in the right direction? I have installed them in the past and as far as my ears can tell they worked fine.
Hang on guys, some transformers have multiple taps and others do not. You have to check on the wires coming out of the transformer. Most are color coded. While having multiple taps gives you flexibility. I think but I am not entirely sure that a single ratio transformer is theoretically better. Ralph may be able to comment on this. Sowter has multiple tap transformers but I have always avoided them. May be just a knee jerk assumption. My brain hates unused wires.  
Chakster, The Sowter trandformer for low impedance cartridges is good for 1-15 ohms. 1:10 or 1:20. 

Not really Uberwaltz, most of the best cartridges now a days are very low impedance. I would just get  transformers for low impedance cartridges.
IMHO an internal transformer is always better. I guess some people are not so hot with a soldering Iron.
Uberwaltz it is very easy to put a transformer in in such a way that the phono amp can be returned to stock and nobody would ever know it had been modified.
chakster, Sowter transformers are British and are made like SME stuff. They cost about $100 per transformer which relative to transformers with a shiny face plate and chassis is CHEAP. Uberwaltz just mentioned a used Ortofon for $600! 
Montaldo, read this.
It will back up what Atmasphere has discussed and give you the math to properly load your cartridge.

chakster, you can always out board them.