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SUT Interconnects

What cables have you tried between an MC SUT box and 47K MM phono stage? What was your favorite?

I’ve tried the AudioQuest upper-line "normal" ineterconnect cables (Sky, Fire) - great cables in other slots - but very colored coming out of a SUT. Not great performance. I assume that at 1.0m+ lengths, their capactitance is far too high for this application. I’ve tried 0.5m runs of Wind & Niagara (a bit lower in their "normal" IC line, slightly smaller guage wire and less shielding to boot) and got better results. However, my best results by far are with a 0.5m AQ WEL Signature LP phono cable (optimized for low capacitance phono applications). I’ve also tried the Bob’s Devices custom cables, 0.7m, both copper and solid silver versions - these have good performance (particularly the silver), but are more on the level of the 0.5m Niagara, still short of the WEL LP.

The problem I have is that the WEL LP is quite spendy, and I want a 2nd good SUT cable for a 2nd arm & SUT setup. Looking for more reasonably priced options. I’ve had excellent results with a Synergistic Research Foundation phono cable on a tonearm (DIN plug), and wonder how a short all-RCA run of it might do off a SUT (also interested in the Atmosphere X series). Any experience with SR or other cables off a SUT would be appreciated!

mulveling
dover
2,308 posts
 

I think that bit of double talk refers to the dielectric effect. Different dielectrics ( insulation) will affect the capacitance of the cable which in turn affects frequency response. Same goes for the spacing between the conductors and the geometry of the cable. All of those factors plus length determine the cable C, which is a constant at all audio frequencies.

Not correct.

  • The dielectric constant can change with temperature, and this change can be significant, especially for certain materials. For example, some ceramic materials used as dielectrics in capacitors can have a temperature coefficient, meaning their capacitance changes with temperature. 

  • Frequency Dependence:

    At higher frequencies, the dielectric constant may not be able to "keep up" with the rapidly changing electric field, leading to a frequency-dependent behavior. This means that the effective capacitance can vary with frequency. 

 

lewm
13,565 posts
 

Yeah, sure. If it makes you happy. The first thing I said is that the dielectric can affect capacitance. As to your other point, what temperatures do you have in mind,given that most of us maintain our listening rooms at between 66 and 72 degrees F? And if T is stable, no matter what the value, there would be no change in C due to T for a given IC at a stable T. Your point about the dielectric vs frequency is interesting. Does it apply at audio frequencies? In any case, do you want to agree with west coast and say that “capacitance varies with frequency “? That’s just wrong was my point. At frequencies much higher than audio, all capacitors begin to have problems; they resonate and can become inductive. I took that aberrant behavior as irrelevant to the question. Ceramic caps retain their properties to much higher frequencies than do other types used in audio; that’s why they’re often used to filter RF.

dover
2,308 posts
 

@lewm

What I did not elaborate on is that with polar molecule material such as teflon, the dialetric constant can change with temperature changes in and around room temperature - we are not talking extreme temperatures here.

The changes in dielectric constant can affect both capacitance and frequency response, along with phase changes due to skin effect and the change in dielectric constant.

The ceramic caps are a red herring here - we are talking about cables - but the science remains the same.

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