Audio Research SP3-a1

@lostbears I heard its greatness. Probably your partnering equipment causing the shortcoming.

Thanks for everybody's feedback, I really love my old SP !

ARC began to worship larger wallets. Your's no good for them. It's OK to send them to go F themselves I guess. Has anyone done that yet?

I know someone who got an old unit upgraded and modified to some "C" specification, which apparently makes it sound more modern. I can check who did the work but doubt it will be much cheaper. I had a new one back in the day- it was a revelation, but that was in the mid-’70s. I suspect it sounds pretty old school tube by today’s standards, but it’s a classic. I eventually "upgraded" to an SP-10 mk ii which was glorious in its day, but man, talk about microphony problems. Bill Thalmann runs a very good shop in Virginia- I’d also trust him with the unit. Perhaps worth a call though chances are, he won’t be able to give you a precise estimate until he opens it up.
PS: i dug back and found the references to my friend's unit. He had Joe Curcio do the work. I gather than the unit can be repaired by Curcio without doing extensive mods but you'd probably have to call him to get a range of prices.
good luck-

If you’re a little handy with a soldering iron take your time and do the repair yourself... it’s really not that difficult. Does the unit play at all or completely dead? Guessing the electrolytics on the power supply is what needs replaced. Get your hands on a schematic if you don’t already have one - they’re out there. Next find someone near you with a tube tester and check your tubes. ARC sales great tubes but you’re going to pay for them. Plenty of places to buy tubes. If you have never touched a soldering iron find a tech locally; where I live I know of several people that can easily work on a SP3. If you liked the way it sounds then why bother updating it, just fix the PS board which is likely only a few caps. I’ve had great luck with cryoset.com for tubes. Parts Connexion, Percy, Mouser, and Digikey for caps and etc. if it doesn’t play at all it could be more. Any burnt circuit board traces? I’d just get the basic stuff done, new tubes if needed and leave it as a SP3 A1 and not spend the money to upgrade it. It’s never going to compete with newer $3K preamps so don’t invest that kind of money on it and besides it sounds like you like how it sounds which is all that really matters.

Been years since I’ve heard a SP3, but from what I recall I’d take a Modwright SWL 9.0 over it. You can pick one of those up used for a lot less. Has a little of the magic of the older ARC but better IMO. I’ve owed one and very much enjoyed it.

Good luck