SUT - electrical theory and practical experience

Some vinyl users use a SUT to enhance the signal of the MC cartridge so that it can be used in the MM input of a phono stage.  Although I don't understand the theory behind it, I realize that a SUT should be matched individually to a particular cartridge, depending on the internal impedance of the MC, among other things.  

Assuming an appropriately / ideally matched SUT and MC, What are the inherent advantages or disadvantages of inserting a SUT after the MC in the audio chain?  Does the SUT theoretically enhance or degrade the sound quality?  What does the SUT actually do to the sound quality? 



Hi @intactaudio ,

Finally, the overload points (1% THD+N) for the 834P were 69.2mV at 1kHz, 260mV at 20kHz, and 7.85mV at 20Hz.

Hi @pindac ,

I had the original EAR 834. I like it but I saw it was built with very cheap components and power supply. Romy The Cat article "End Of Live Phonostage" inspired me to build my DIY EAR 834 with better parts (including air capacitors, z-foil and AN silver Tantalum resistors, Jupiter signal capacitors,...) and power supply with LCLC filtering, parallel voltage regulator based on 0A2 tubes and different other upgrades.

So, my DIY EAR 834 is a different animal compared to the original one. The schematics is very important but the implementation is even more.




Hi @rauliruegas ,

Yes I use these Tamura SUT with box build by myself without switches. All wires are directly soldered to RCA. 

But I thinking to built a new box for my DIY phonostage where I want to place SUTs near input tubes. So I can rid of SUT to phonostage interconnects.




@drbond  : What happens with an external SUT about all those additional " steps " where the cartridge signal must pass through is almost the same when the cartridge signal from your CH must goes to an external line preamp and that additional step makes nothing but signal degradation but exist something additional in your electronics and is that the cartridge signal suddenly must pass through a way different line preamp design not a CH unit to preserve at least same " signature ".


That's why normally is better to own a Phonolinepreamp where we have to add nothing to the cartridge signal.