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

Maybe I'm a little " stupid " and don't understand your way of thinking or what you are looking at and I said that because you are thinking to in the time add a SUT to the CH and what do you need to add that SUT?:

 

well obviuosly the SUT and an IC cable and what does that means?

that the valuable and way sensitive cartridge audio signal not muts pass through a pair of additional SUT input connectors that degrades that signal as does too the solder joints and from there the audio signal will continue hislong tortuose path through the " hundreds " meters of transformers wires that react to the cartridge signal and that follows the degradatio  but this is not the end because the signal now must pass for other pairs of SUT output connectors and solder joints along the IC cables. Why all those long totuose path against your today DIRECT cartridge audio signal path? Makes sense to you? if yes, then  go a head. No problem with me.

@rauliruegas

With your extensive experience and knowledge, I think you really could contribute positively to these audiogon threads, but somehow, I think you just do not comprehend the details of what is being discussed. No, I never said, nor is there a "problem" with the Ypsilon monoblocks, and so far I’ve yet to hear anything that is as transparent, delicate, and detailed, with proper timbre as the passive Ypsilon pre-amplifier. . . but let’s not hijack another thread into another topic, as this is just for SUT discussion.

Now discussion of how signal is actually transmitted through a SUT would be quite interesting: does the signal actually move through the wound wire? As we know, the electrons in a wire don’t travel. . . do you think that the signal is rather transmitted via the core, and not the wires? What really happens to the signal? I don’t know if anyone really knows (but I’m not an electrical engineer), but I do know the limitations of human knowledge. Now, how much of the signal is purely electrical, and how much is magnetic, and can they even be separated? I suppose now it gets into a "religious" argument, where our minds may not be able to comprehend the exact way that everything works.

I hope you enjoy your weekend!

Now discussion of how signal is actually transmitted through a SUT would be quite interesting: does the signal actually move through the wound wire? As we know, the electrons in a wire don’t travel. . . do you think that the signal is rather transmitted via the core, and not the wires? What really happens to the signal? I don’t know if anyone really knows (but I’m not an electrical engineer), but I do know the limitations of human knowledge. Now, how much of the signal is purely electrical, and how much is magnetic, and can they even be separated? I suppose now it gets into a "religious" argument, where our minds may not be able to comprehend the exact way that everything works.

The coil(s) in the cartridge outputs a current based upon maxwells equation description of a magnetic field moving across a coil.
So it is an electric field that is pushing the electrons along in a back-n-forth AC fashion.

In the SUT, the current creates a magnetic field from the input winding of the coil, and the output winding creates a voltage and current to fight (or in response to) the magnetic field.

And yes… the electric field pushes those electrons along, which in an AC field result in no net significant movement on the average over time.

 

 Now, how much of the signal is purely electrical, and how much is magnetic, and can they even be separated?

A cartridge, SUT and speaker driver, all have a significant magnetic field component to their design.

 

I suppose now it gets into a "religious" argument, where our minds may not be able to comprehend the exact way that everything works.

Maxwell’s equations are at the core of “the religion” of what is happening. EEs are generally the ones that comprehend this to provide the designs to manifest “the religion” into reality.

Drbond, transformer theory is a deep subject. The only person with deep knowledge who ever posts on Audiogon is Dave Slagle (Intact Audio). Otherwise you are not going to find enlightened discussion here. I suggest you do an internet search. The subject interests me as well. For example, some who dislike SUTs like to lament the concept that the signal is actually traveling along the many yards of fine wire that make up the primary winding thereby suffering degradation even befor being transformed. But I think there is some basis for treating the primary winding as a singular entity. Dave could speak more eloquently on this but also you might find such a discussion on line.