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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
westcoastaudiophile
496 posts
 

MC to SUT connection is a “low impedance: high current, low voltage” one, while SUT to Phono-amp is a “high impedance: low current, high voltage” variant of it. SUT to Phono-amp connection is very sensitive to RFI and other outside noise, thus shorter connection is better (ideally SUT is integrated into phono-amp). To optimize performance of MC to SUT line, need to check resistance between each of head-shell wires and phono cable SUT input ends. Resistance of each line should not exceed 0.5Ohm (in my setup ~ 0.1Ohm). Aged tone arm wiring, oxidized contacts could cause significant resistance increase, which will negatively affect SQ. Capacitance of MC-SUT cables is less important, than SUT-Phonoamp ones, because resonant frequencies are much higher than audible range there. 

good overview online: https://myemia.com/Loading.html

billstevenson
550 posts
 

This discussion prompted me to experiment a bit.  I use Audiosensibiliy Statement Silver interconnects throughout all of my equipment.  I tried 0.5 meter. 0.7 meter, and 1.0 meter phono cables on both inlet and outlet of both Bob's Devices Sky 10 and Consolidated Silver SUT (10:1), cartridge was SoundSmith Experion, C-J ART Phonostage.  The limitation is undoubtedly this old man's ears, but frankly given the time lapse between each setup, I could not discern any difference between any of the cable lengths.  The Bob's Devices SUT is a shade warm compared to the Consolidated.  The latter has slightly better micro detail, but you have to really strain to capture the difference.  But again and in keeping with the spirit and intent of this discussion, cable length differences in my experiment were not a factor.  Note, I kept inlet and outlet lengths the same in all cases.

rsf507
2,407 posts
 

Curious how one measures capacitance of an interconnect?

atmasphere's avatar
atmasphere
12,113 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
13,585 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.

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