SUT Advice - Which Ones Are The Best?

If the phono stage has gain settings up to 60 or 65DB in addition to impedence selections for cartridge flexibility, why do you need an SUT? It would seem logical that more connectors introduce more distortion.

If you are talking about an SUT instead of a phono stage because the impedence is already well suited or in addition a phono stage that has no gain capability, then I guess it makes sense.

Am I missing something?

It would seem logical that more connectors introduce more distortion.

distortion that you can't detect

I have a Dynavector SUT, was hard to find, even harder to get documentation like a users manual (from dynavector that is) and expensive. But oh so nice, quiet, smooth, detailed and lush. Of course that’s with a Dynavector XX2, and run thru my McIntosh MX110Z. Highly recommended..

sokogear, I think you have a pretty good handle on the situation. Never heard one myself so only know what turned up after a ton of research. These things are transformers, very specialized transformers at that, and so they are more a way of tweaking or fine tuning the cartridge than anything else. There are whole websites devoted to the subject, with in depth reviews of far more different SUT than one would think even exist! Never even knew so many were out there until I started digging into it.  

This sets up the perfect situation for some to be able to say the SUT is essential and others to say forget it what a waste, and both be right. Because if you luck onto one of them that is really good for your particular cartridge and phono stage then boy oh boy will you be happy. But you could just as easily wind up with nothing or worse, a royal headache. 

The sensible approach I think is what Decware does, make a phono stage designed for high output carts, and then offer SUT in various gains to suit different MC outputs. You can also trade them back in for another in case you need to for cartridge changes. This avoids yet another pitfall of SUT, trying to sell for used something hardly anyone wants to buy new. Take a bath, you will!

@sokogear

If the phono stage has gain settings up to 60 or 65DB in addition to impedence selections for cartridge flexibility, why do you need an SUT? It would seem logical that more connectors introduce more distortion.

@billwojo summed it up nicely. The reason you "might" want a SUT is because it may sound better. Passive SUT vs active gain stages in order to get to the 60-65dB gain. Transformers have much more benign distortion characteristics than active circuits and are capable of producing a wonderful soundstage with detail and separation compared to transistor and op-amp alternatives. The main issue really is cost - transformers are incredibly expensive compared to transistors and chips. A complete MC phonostage is obviously more convenient than a separate transformer and MM phonostage. The MC phonostage made entirely with solid-state circuitry is way cheaper to produce than one with transformers.

In every case I have heard I prefer the SUT....but that’s just me, my gear, and my ears. To each his own preference.