Audio Research SP3-a1

 ARC does not charge excessively for repairs. What did they say was wrong with it? A unit this old may have a number of issues but ARC will go through it with a fine tooth comb. It is worth the cost.

 Has your unit been "modified"? If so ARC will insist on removing the "modifications" before it can be repaired. This is a classic piece, I would not let just anyone work on it.

My SP3-a1 is a stock unit and they want around $1800.00 to rebuild the power supply., then they were going to look at the audio section.They also offer an up grade to the SP3 for $2900.00 plus tubes (no shipping)!   Maybe I'm just out of touch with things cost today !                                                                                              Thanks

Unless this unit has sentimental value, I’d put it in the closet and look for a clean ARC LS-2B with remote ($1000 to $1500).
BTW, $2900 today was worth $900 in 1980. Also, there are three for sale here as I type.

Don't send your SP3 to ARC! They are just preying on your gullibility! What do you think is wrong with it: distortion in one channel, higher noise level, persistent hum, lack of gain ... ? Most of these problems are simply due to tube aging. Tubes do not last forever! Try to find a competent technician in your area! You can also try contacting Audio Classics in Vestal, NY. I have dealt with them before and have been satisfied with their service! Also check the back page classified ads in Vintage Guitar magazine for contact info on "tube amp repair" services! This might be your best bet for service at an affordable cost.

 That does seem excessive. It has only cost a few hundred dollars both times I sent pieces to ARC. I agree, would put it in the closet. For that kind of money you can get a much better preamp.  The LS2 and LS2 mk2 would not be on my list. I had a LS2B mk2 for a few years in the late 1990's. It was good in it's day but never great.

@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

For $3,000 you can get a used Herron VTSP-1a which will blow away the SP-3a.  And most $200 phono stages better the early ARC preamps by a long shot.

Purely for informational purposes, from that legacy database of ARC stuff: http://www.arcdb.ws/SP3/SP3.html 

Love the black and gold faceplate now. It's totally pimp. I thought it garish when I bought mine new, and went for silver. 
PS: schematic for SP 3-a-1 in the link if you scroll down.

I remember retubing mine in the early '80s- a raft of Telefunken 12AX7s. Cost a total of around $80 for the entire complement. 

Update on SP3-A1, I decided to let ARC do the repair, It was up there (at least I won"t lose  the shipping) . The pre amp will have a warranty and full documentation . What the Heck ." Life is to short "!

Good to get the monkey off your back!

Got another bag of Monkey's, I have  an old D-150 ARC amp., that needs some attention also !

 I sent my V70 amp to Audio Research some years ago. The amp was almost 20 years old at the time. They did a superb job on it and the inside looked like new. I think they actually cleaned the circuit board. I would not be surprised if they do the same type of thing to your preamp. They want to clean every thing thoroughly and check every connection so it sounds it's best. Let us know what happens when you get it back.