Recapping an ARC LS-5 mkiii


So I have done an exhaustive Internet search on this, and have some answers (but not all).

Every piece of audio gear I have from the 80's and 90's has had some sort of issue and needed mods and/or repairs. Some of this wasn't audible, but showed up when the equipment was put on a test bench.

Every piece of classic/vintage equipment I have (Aragon, Sonic Frontiers, Audio Research) has been updated except for my LS-5 mkiii preamp. With ARC gear, I know lots of people tend to think of them like classic cars and look down anything ARC didn't do originally.

At the same time, I know ARC offers a Stealth Cap upgrade (roughly $800 IIRC) and I also know Steven Huntley at GNSC used to modify ARC gear (including the LS-5), but I can't really find anything out there on what that process involved.

I am interested in getting the Stealth Caps done, however, outside of that, I don't want to change the sound signature too dramatically (like shoehorning an LS V8 motor into a Mazda RX-7). I'm sure there are some gains to be made (Rel Caps to Infinicaps?), but want to make sure I do things the right way.

BTW, the preamp sounds good (to me), but as I've learned, that doesn't always mean it would test completely within spec.

Thanks in advance.

atlvalet

It is best to let ARC do the upgrade.  At least you won't kill the resale value of your preamp and you know it will be done professionally.  

Avoid capacitors whose manufacturers don't specify a ESR or a ESL number.  Anyone in a garage can make a cap that works but the equipment to measure ESR and ESL is expensive and you do want those numbers.  At least you have a very good idea of what the capacitor will sound like, assuming the numbers are honest.

Slim to zero chance ARC will work on the unit if it has obsolete semiconductors (they can't take the chance they'll accidentally damage an irreplaceable good one while in their care). 

The Rel Caps are top quality films which ARC uses as bypasses in the power supply. I don't know what they use in the signal circuit. I think you may be doing a sideways upgrade if you replace the Rel Caps. I look for old damaged ARC gear to harvest the Rel Caps.

LS 5 mk 3 one of the all time great pre from ARC a true classic believed to be the first REF. Pre they made. I always wanted one and would buy the right one in a heart beat and would also upgrade the caps. Extremely rare to fine one for sale showing how treasured they are.