Is Audio Research SP-6 considered a good model?

I'm trying to decide on how to replace my Plinius 9200 with separates. I have a 70's era SP-6 and I'm wondering if it's worth servicing and keeping, or are there other tube pre amps (Audio Research or otherwise) worth looking for used (1-2K range). Also have a AR D52B that I will definitely be replacing.

Totem Forest speakers
Rega P3
Exposure 2010S CD
There were so many versions of the SP-6, and not all of them were considered good, that it is really difficult to answer your question. If it is the original 6, it could definitely be improved with cap and resistor upgrades for probably not too much money but you have a competent technician do this work. ARC will charge you an-arm-and-a-leg to do this and I really can't say if this would represent good value (but I doubt it).
Very good piece in its day and still should be very good.However I would invest in a test bench professional to go thru it and get as much out of it as possible..I think there is a company called "Great Northern" that specializes in upgrades etc on Audio Research vintage stuff.. For what you will invest you won't find anything,thats for sure...
Theres also a company in Framingham,Mass called Natural Sound that has been selling/service for many years.They did a nice job on a SP8 of mine awhile back.They are still around at the same location.....Good Luck
the arc is a great peice, put honestly your totem/plinius combo is so good, i can't help thinking you will get 'different' but to improvement. think really hard about this change, and consider that a balanced tonally accurate playback system doesn't jump out at you (refering to the tube amp's euphoric mid's). arc is great tuber gear, and more reserved than some, put play lots of big, complictated music and really scrutinize how your sysyem reacts....yes those simple recordings are gonna sound a little more holographic with the arc, but the soundstage is just part of longterm listening fun. in any case, best of luck
ARC estimated $700-800 for the work. I know there were other models with letters e.g. SP-6A... don't know if there were different versions of the SP-6. I'm also wondering what power amp would pair well with the SP-6......
Well Jaybo thanks for the advice...I am listening pretty hard...I didn't find big orchestral music to be very well handled on either the Plinius or the ARC......I thought maybe in the case of the SP-6 that I didn't have enough power to fully exploit its qualities.....
i also think you might be impressed by the new cyrus 8 integrated....and the new creek 5350 (both compete and control well beyond their retails) .....well within your price range, and both 'a bit' livelier that the darker plinius character. comparing may help you sort this out before commiting....the forests are great, and your exposure player is also a giant killer.
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i still use it in its original state together with wadia 581 ml 431 , i currently drive the power direct , but the sp 6 can add still some nice tuberealism very very good value
The ARC 6 was good! The 6-A was better!! The 6-B was one of the best per-amps ARC made. This was right before the SP-10. After the 6-B ARC came out with the 6-C, 6-E and from then is went down to just good. The "white" sound came into the picture and the flesh and bones of the orchestra and musicians started to fade. The SP-8 is also a better model then the 6-C, 6-E.

Rick (RWD)
I agree the SP-8 is definitely a good model, especially at the used price, an improvement over the SP-6. I have owned both. The SP-10 Mk2 is even better. To tell you the truth, I still love the sound of this pre-amp even compared to new models and would trade my Supratek Syrah for one in a heartbeat, love that phono stage! I have a friend who owns one and no it doesn't have the detail or extension of other pre-amps but it really draws you into the music so you can just forget about the sound. The SP-8 also does this but doesn't quite match the immediacy, depth or bass weight presented by the SP-10.

It is easy to see why there is still interest in these models.
I would definitely talk with Steve Huntley at Great Northern Sound. The SP6 is on his list of packaged mods which means he knows the potential of this piece of equipment. Steve's a great guy to talk with and he will give you solid advice. I have nothing but praise for GNSC.

Check it out...

classic. in its day it was the consesnus best preamp.Not likely that it could compete with todays preamps. I think you should keep it un-modified. You have got a piece of audiophile history. Mate it with an ARC D79 and say a pair of quad esl 63 and entec subs.
Well it turns out that my amp is actually an SP-6A- I didn't realize that you had to check the back plate to see the exact model. I'm wondering though if I should give up on the Plinius yet,I've read that the PC makes a big difference. I'm using a Top Gun HCFi- it's so big that i can't plug it straight into the wall- maybe I should try another PC?
I use to own a SP-6A, SP-6B.ARC had other mods done on them with ARC SP-6C, 6E, i BELEIVE AS WELL.I had heard that a rare SP-6F was made which is actually a SP-8 in a SP-6 outer shell. The amps of the day that worked well with the SP-6 were the ARC D90B. I used a Hafler DH 200
Solid State Amp when I had the arc preamp, and a Ram Labs Head AMP for additional gain in the phono stage and all had it hooked up to Acoustat ELS SPEAKERS.Boy does that bring back memories.