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? 

Thanks. 

drbond

Dear @holmz  : What Dover posted. You can read the link rigth from the Ortofon cartridge/SUT specs and then the measured sqare wave.

 

R.

Dear @holmz  : What Dover posted. You can read the link rigth from the Ortofon cartridge/SUT specs and then the measured square wave.

 

R.

it would have been handy to have a physical triangular wave - cut into the track… and then everyone would be able to generate the square wave without needing a signal generator,

@holmz ​​​​​​

the CBS STR-112 has a 1kHz square wave for the test you propose but be warned the results of this test from a cartridge is not for the feint of heart. And yes as you suspect due to the riaa filter the actual cut of the track appears as a triangle wave.

dave

holmz ​​​​​​

the CBS STR-112 has a 1kHz square wave for the test you propose but be warned the results of this test from a cartridge is not for the feint of heart. And yes as you suspect due to the riaa filter the actual cut of the track appears as a triangle wave.

dave

Thanks Dave - I ordered one.

It might not be a triangle shape from the RIAA. But it will be good to try it.

Dear @holmz : Could be interesting to make some tests looking for the transient response rise time of a cartridge in an active high gain phono stage and other using SUT.

 

Exist a very old measurements made it by an electret vintage cartridge designer where he found out that the rise time of his designs was 2 micro seconds at 1khz generated square wave ( Osciloscope. ), moving magnet 25 micro seconds and a moving coil through a SUT 30 micro seconds.

 

That rise time is critical in transientes response by obvious reasons and you like to make measurements maybe you can do it. Just curious.

 

R.