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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
atmasphere's avatar
atmasphere
12,110 posts
 

Curious how one measures capacitance of an interconnect?

@rsf507 By using a meter which measures capacitance. You treat one connection as one lead of a capacitor and the other connection (perhaps the shield) as the other lead of a capacitor.

lewm
13,567 posts
 

What Atmasphere said, but be sure to disconnect the cable at both ends before taking a measurement.  For a balanced cable, the measurement between pins 2 and 3 (positive to negative phase) will be equal to about 0.5X the capacitance between pin 2 and pin 1 (pos phase to ground) and between pin 3 and pin 1 (neg phase to ground), because capacitors in series add like resistors in parallel.

westcoastaudiophile
489 posts
 

"By using a meter which measures capacitance” yeah.. capacitance changes vs frequency, that’s why I measure capacitance / inductance / loss / resistance at 50/1000/10000/20000Hz points. 

displayname's avatar
displayname
165 posts
 

You've already tried Bob's cables, so I can't add much value here but that's what I'm using. When I purchased Bob's SUT I got his cables because it's what I demoed and I mentally just considered it part of the system. 

lewm
13,567 posts
 

No, westcoast, capacitance does not change with frequency.  What you are thinking about is that because of capacitance, impedance changes with frequency.  (Impedance of a capacitor is infinite at DC and goes down as frequency goes up, by an amount dependent upon the value of C.) But that does not matter when you are simply concerned with the capacitance of a cable, or rather impedance is inherent to the question of whether a certain level of capacitance will cause a resonant peak because of interaction with inductance, the other major player in determining the resonant frequency.  Capacitance and inductance are properties of reactance. You only need an accurate and sensitive C meter to measure C. That value does not change with frequency, at least at any audio frequency. (It will change at RF frequencies in the megaherz band.)

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