Any Members Tried the Audio Interface CST-80 SUT?

I already had the Cotter Verion SUT at the time I bought the AI, and was able to compare them in the identical system without relying on ‘audio memory’: it only took a second to switch back and forth. I also had a ‘Jury of Golden Ear Friends’ who helped me assess and choose whenever I got new components. Two were musicians, one a sound engineer, and we used recordings they performed on and knew intimately, or were present at the sessions.

I heard NO difference. But all three of them preferred the CST-80. One, a violist with the Berlin Philharmonic for over a decade, preferred it by a wide margin: he thought it captured instrumental timbre better, especially important to him.

I decided to part with the Cotter, but as I mentioned I heard no difference. My friends’ judgments swung it for me, plus the AI is only one-third the size, fits under my turntable, and is considerably more attractive. It also allows you to try different cables (eg copper vs silver, floating shield, etc) whereas the Cotter has captive leads of older design.

I’ve used it with many cartridges over the years. It has no loading options (neither did the Cotter) so you must look to your preamp for that. Sometimes I switch to a head amp (Thorens/EMT) but always return to the AI.

I look forward to your ‘review’ when you receive it, and how it compares to your FR.

I’m searching memory back 20 years as to cartridges I used. It included — Accuphase AC2, VDH MC10, Linn Asak, Coral (aka GAS Sleeping Beauty), Blue Oasis, Audio Technica OC-9, Madrigal Carnegie One, Dynavector 23 Ruby, Ortofon MC20 Super and MC30 Super, Audioquest 909, Fidelity Research MC 201 and FR1Mk3F — that’s all I can recall now.

All sounded lovely, within their own limits. A couple were irritatingly strident in the highs, and I blamed either the cartridge or the CST-80 — but they may have been innocent, I didn’t know much about loading then. It is the mythical “straight wire with gain”, though of course it’s wound wire. (Or possibly wound foil; such a shame so little info is available.)

I mentioned a Thorens/EMT head-amp last time. I like it a lot, it’s dead-silent and has better dynamics when I’m using a passive preamp. But I invariably move back to the CST when using active preamplification, either tube or SS — its transparency and purity is utterly beguiling.

Remember, I’m expecting your review...

But it handles my FR1Mk3F’s 0.14mV easily — in fact, with the volume on my preamp at only 8 o’clock, it’s blasting. Your 0.2mV Spectral should be fine — though its impedance is wickedly low.

Your dilemma is superior SQ (though not by much) vs Versatility. If you’re like me, I’d go with versatility... but always feel something’s missing, now that I know what’s ‘not there’. I’d always miss that extra ‘something’ and inevitably go back to the CST. But you have two great SUTs, and that’s not a bad dilemma to have. Our pursuit of the divine in music is fraught with dilemmas.

You can buy, or make, a switch-box to handle more turntables — but will that degrade SQ? A bit, probably — the FR’s switching capabilities may account for it’s slightly lesser clarity.

Even though its captive leads are old I’m sure they’re good (it’s FR after all; they used silver coils in their MCs at the time). I’m not sure replacing them with RCAs would help. At least the old leads are a direct signal path — yes, you could use “better” ICs, but chopping the signal up with additional solder-joints and plug connections might nullify any benefits a “better” cable could give you.

You’ve probably seen this review/lab-test of the CST when it was produced; it contains thorough data:

http://www.gammaelectronics.xyz/audio_12-1982_audio-interface.html

The site is also an archive of old reviews of serious equipment, fun to leaf through...

PS — No need to apologize for the long post — it wasn’t long enough! I'll be very keen to read your further ruminations and conclusions...