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

Please also make sure that all those tiny multicoloured wires from the SUT are soldered properly. I once had the orange one loose on the R channel and that diminished fidelity.

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.

Tom: I am a pretty handy guy with most things except Electronics. I'm just terrible at soldering. But I have a local Tech who is great. Good to know that Dave units tend to be good in the mid-range because that's my highest priority.

Mijostyn: yes I expect this will be some trial and error. When people talk about overloading the preamp is it possible to actually do it damage, or is the overload more a sonic artifact that is not helpful?
I only tried the Hashimoto for about an hour in my system and I'm not sure if it was set for 15x or 30x. I certainly didn't hear anything negative in terms of an overload.

Dear @montaldo  : """  I think our respective objectives in this Pursuit might be very different.  """ Could be you are rigth.

My overall room/system target ( main target. ) is that what I listening through it be stay nearer to the recording.
Then my quest is to acieve that target that puts me nearer to what the recording microphones pick-up that puts me nearer to the " real music " ( it's imposible to mimic live music experience in any room/system. ).

For that can happen the room/system must be a very high resolution one and at the same time with very low distortion levels at each singhle link in the room/system audio chain. That is true HiFi, not what refferd Tom.

Now, in " paper " those Jensen are very good transformers and for many years Jensen was and is a reference in audio, several high end manufacturers use it:

https://www.av-iq.com/avcat/ctl1642/index.cfm?manufacturer=jensen-transformers&product=jt-347-axt

I know that numbers does not say all but are important.

Hashimoto as other transformers are good too but in the case of the Hashimoto and due the way of thinking of the manufacturer amybe just maybe what you are listening trhough it more than a real an better " dynamic " characteristics against the Jensen in your Berning been only a different kind of distortions not only because the SUT but because the additional IC cables and connectors.
I think that way because you said the differences for the better is not a tiny one but something important.

In the other side, through the years you owned the Berning and after the burn-in time the quality level performance  of that unit changed in any way?

Because could be too that through the time something " degraded " the Jensen performance as " cold " wire solder down there ( with so many wires. ) or even one de-soldered.

It's imposible to figure out what is happening in your room/system because no one here already had your experiences betwwen the Berning and the external SUT.

Btw, @mulveling  the KRSP ( that I owned. ) is way different to the Koetsu OP model. The KRSP output level is 0.2mv and the OP is 0.4mv. As a fact both models only shares the Koetsu name because the quality level performance is way different in favor of the KRSP.

R.

 I have only owned the berning preamp I have only owned the berning preamp for 2 months so this is not a change that happened over time. I  I think I may have mentioned that my time with the Hashimoto sut was very limited but the impression of dynamics differencess was pretty stark.
 the interconnects I used with the sut were the exact same that I  using the rest of my system, so well every interconnect adds some sort of flavor or distortion, I don't see it dition of one more as possibly creating the difference I was hearing.