SUT vs. Phono preamp

The ISO-MAX Jensen SUT should be nearly identical to the Audio Interface (and is easier to use with the front and rear separation for input and output).  It is very reasonably priced if it is the same transformers.

If you are on a budget I would go with an SUT, if you plan to use a low output cartridge. If budget is no concern, I would go with a good phono section capable of low output cartridge operation.


There is more than just noise to be concerned about. SUTs must be properly loaded so as to not ring (distort); this loading depends quite a lot on the cartridge used; IOW varies depending on the cartridge.

An active phono section will probably have more noise. It might also have more bandwidth; personally I prefer the improved soundstage and detail I get from going direct. But it doesn't always work that way so in a very general way, that is why I made my initial recommendation.

Yes, Benz cartridges are not known to be SUT happy and prefer phono stages that can increase output without transformers.   However, in my case, the Audio Interface is an ideal match for an SUT.   My cable maufacturing friend built a low noise, subminiature tube step up but we couldn't get the impedance just right through changing of resistors.  It still had substantially more noise than I wanted to live with.  

I have a Premier (Sumiko) S.U.T. and a Pre-Amp, like Boofer posted earlier, I can't hear a difference. 

On what basis? Try it.

Hook up your cartridge to your phono stage and listen to a record cut at low volume levels, set to the volume you like to hear.
- Do you hear distortion?
- Does it play loud enough?
- Lift the cartridge. Do you hear a hissing noise?

If you answer ’yes’ or ’no’ or ’yes’, then a good SUT will help. How good? About as good as your cartridge. Oxygen free SUT’s from Sowter are very good, but the amorphous core - silver wound SUT’s from Lundahl are the best I’ve ever heard, and I’ve heard some very good ones.

Even so, my phono-pre is marginally better for dynamics and weight with a platinum Koetsu.