ARC LS15: did they ever use Mundorf MCaps on it ?

Johnsonwu.....Amen with last post.

To the OP, If it has a GNSC badge on it no worries. Steve Huntley's (and his team) workmanship was without fault. He used premium parts as well IE; Vcaps, Vishay, Caddock, and others. I had many units modded by him including (but not limited to): REF3 LE, REF2 Phono, Classic 120's, DAC7 with astonishing sonic results.
Actually, when you look inside a REF5 SE and REF2 Phono SE you can clearly see some of Steve's signature work that i have in my units particularly the power supply upgrade.

.......and to the modder detractors, the launch of ARC was orchestrated by one of the most renowned modder of its time pre 1970.... William Z. Johnson.

Yes, a modded unit's resale value would typically be less than stock although i have sold a few ARC GNSC modded units at premium prizes over the years. There is a niche market for modded units including ARC's.

No, unfortunately it was not modded by GNSC: that would have been a different matter, indeed.
I know people, even here in Italy, who are very able at modifying electronics and I would trust them; Huntley is world famous and he would sure be one of them (btw: is he out of business ? I think I've read something about it).
But that 15... no one knows who put his hands in it.
Anyway, now that's past. :-)

Thanks again to you all.

Good luck with the ls16 bid

GNSC is no longer in business.

HifiGeek, you have all my respect for your knowledge of Audio Research gear. If I recall correctly you are one of their official off-factory repair depots. I sincerely hope you dont view GNSC's cease of operations as a one less competitor. Huntleys mods are expensive. But for many of us it sure beats paying big $$ for trade arounds.