1970's Audio Research Equipment, worth having?

ARC seems to held in high regard by quite a few 'Gons. What about the early tube stuff, like the mid 70s? Does it still measure up to today's standards? What are some the problems one might face?
Audio Research made the biggest change/advancement in the mid/late 80's with their solidstate-and-tube designs, for both amps and preamps, better know as "hybrids." A perfect example is an M300 MkII I have for sale on the Gon right now. This vintage and later are easily repairable and upgradeable but the earlier ones sometimes present parts matching difficulties (depending on the part) Usually tubes are not a problem.

As far as measuring up to todays' standards, the early ones, no. Mainly because component parts have improved so much. Later ones can be upgraded where it counts (which ARC is happy to do for a price!) and can be made to come pretty close.
I agree with Nsgarch that in the late 80's ARC made changes in going to hybrids...BUT i will not cede that this was an advancement. :-)

I'm not up to speed on ARC's amps. The only one I've ever owned was the D115II - I never warmed up to it for various reasons.

However, the SP preamps made in the 80's were fine then, fine now, and are fully supported by ARC. They all have different sounds, come with very good to world class phono stages, and give up little to todays stuff other than a bit of resolution for which they make up in tonal balance, mid range bloom and their ability to throw a hugh soundstage. They are not cold and ascerbic as are many modern pre-amps, tubes and SS.

I've been running my SP10II since about 1983 - I send it back to ARC about every five years for a tune up. The service is 1st class - and get this, they don't take credit cards. They just return the equipment and send you a bill in the mail! Guess who they trust .....and support.

The SP8 also gets high marks. The SP11, its first hybrid also gets many great comments, although for me it was the first step away from the traditional tube sound. The SP6 is less resolved than the 8 or 10, and the SP3 is lush.

If I were in the market for the sound from these 80's units I mentioned I wouldn't hesitate for a minute to buy one.
If you want older ARC gear, I feel the peak of ARC was from 82-85 or so with the SP-8, SP-10, D70, D115, D250 models. Once they headed into the hybrid line, their sound became way too analytical for me. If you want a sound that is a refinement to the models I have listed, you have to go to the PH2(solid state phono), LS5 & VT130 / VT150. These retained the magic of the 80s pieces with many refinements. I have not heard anything in the ARC line since these models that has caught my attention.

One thing I can say without a doubt is that ARC has made some phenomenol gear and some that was not! Buying a newer product with the assumption that it will be an improvement over the previous model can result in disaapointment. But this is true with any company.

I will offer a somewhat differing view. I agree with the above comments that the hybrids marked a downturn in ARC products-- at least to the qualities I listen for. I have worked on most of their gear up to the mid-1990s. The best amp they ever made, IMHO, was the M-100 and the best preamp being the SP-10 (although keeping 12 quiet tubes in it was a challenge). However, do not assume that the 70s vintage stuff is over the hill. Updating the coupling caps, some resisitors and the feedback caps will give you an amp, or preamp, that is highly competitive. If you are technically inclined, some work on the power supply will then give you an amp or preamp that is as good as you can buy. The output transformers of the 70s tube amps are excellent quality.
one thing is for sure stay away from a d90 man did those things blow up, the d250 on the other hand was a fine amp and very reliable even with all those tubes, d79 also was a great amp very big and heavy though, same with the 250
Thanks for the info received so far. It is interesting how even a well respected company can bring out a new product that is not an improvement over past models. ARC has been around for a long time in audio terms. I wonder how many companies today will be around in 30 years? Take a look at an issue of High Fidelity from the 70's and see how many companies have come and gone.
I bought an ARC D76A from Lyric in 1977. I sold it to a friend about 8 years ago. I continue to be impressed with that magical midrange (he is using it to to drive a MG 3.6). I still regret selling it to him. I also owned the D115 MKII for 12 years. I now own the VT100 MKII.

The topolgy of the VT100 is essentially the same as the D76A, with better parts and beefier power supply with solid state power regulation. All of these amps are very smooth and musical. The VT100 MKII is more refined and transparent with greater control and punch in the midbass and bass.
My oldest piece of equipment is an ARC SP9 mkII preamp. Perhaps not the best ARC as done, but certainly not the worst. A few years back I listened to the LS25 thinking it might be time to upgrade. While I felt it was a definite improvement, it also had a high price tag. As I was looking at alternatives, I stumbled on Steve Huntley at Great Northern Sound who does mods on much of the ARC gear. After much discussion with Steve, I had him apply his reference mod on my SP9 and have to say the results were simply remarkable.

Steve knows ARC gear inside out (he used to work for them) and if there's a particular piece you're interested in, I'd definitely give him a call... www.greatnorthernsound.com
I also owned the SP9 MKI and MKII, the SP14, LS2B MKI and MKII and currently the LS25 MKI. They were all very good to excellent preamps. The SP9 MKII is a steal on the used equiptmet market. One of my friends who is also a dealer still uses the SP9 MKII in his home system after about 10 years.
If anyone is curious, the LS 1 is the same as the SP9 MKII except it is line-level only.
As the posters above have pointed out, ARC has had a long and distinguished history of making audio equipment. Some of their equipment has received more acclaim than others, but there is little doubt that the company was way ahead of it's time in the 1970s. The SP-3A1, the D-76A, D-150, and the D-79 were and still are excellent pieces of equipment. This is not to say that if you have an unlimited budget you can't get better sounding equipment 30 years later (ARC would certainly say you can), but dollar for dollar in 2005 dollars, each of these pieces of equipment (when you can find them in well cared for condition) will sound as good as or probably better than just about anything you can find for a similar price regardless of manufacturer or when it was made. Setting aside how they sound, if you buy one of these 1970s models for fair market value on Agon you will have a strong investment that will hold its value. For example, if you could find a SP3A1 in 7 condition on Agon for $1000 or so you could buy it and listen to it for a year and then probably sell it for the same price. How many other pieces of equipment can you say that about? Not many, and probably no preamp that could buy for $1000 would sound any better than a SP-3A1, except possiblly an Audio Research SP-8 (which happens to be a 1980s model and will probably cost a bit more than a SP-3A1). You can debate which will sound better a SP-3, 8, or 10 (well, ok the 10 wins, but it's $2.2k) or which is a better value, but whichever model you buy based on synergy with your system and your budget, you will have a highly enjoyable listening experience and you will get your money out within a few weeks of the time you list it on Agon.

Finally, as the posters have noted, service doesn't get any more friendly or helpful than it is at ARC. And this is important because to be square, anything 30 years old could need some parts or service (and that's true whether it's solid state or tubes.) In fact, it's probably hard to come up with many (any?) other pieces of equipment from the 1970s that would be as easy to get serviced. The list would probably be zero if you want to have the service done by the manufacturer. ARC just stands out a cut above when it comes to both sound and service.

Is ARC equipment worth it? Absolutely. - And this has been true across 3 plus decades.
Well i know this I had the D350II Solid state Power amp was from 1970's. Nothing special at all just heavy.
ARC has had an occassional notable solid state piece of equipment but I think they are largely known for their tube equipment. One solid state device that is a sonic winner is their CD-3 MkII (cd player) - it happens to be about 3 decades beyond this thread's timeframe.
Having owned a lot of the gear that Audio Research built in the 1970's and early 1980's I can speak from experience....
Pass on the D-100, D-110, D-111, and D-350 solid state amplifiers as they were all early efforts into solid state design from Audio Research...and the sound is disapointing. Later Audio Research solid state amplifiers built in the late 1980's and 1990's were much better, such as the D-130, D-200, D-300 and D-400.

The D-79 and D-150 which were originally developed in the 1970's are classic/collectable Audio Research designs and hold up fairly well when compared to later units. I always felt the D-50, D-51 D-75, D-76, D-90, and D-160 had that "soft tube" sound and lack the high definition of the D-70, D-115 and D-250 series.
I can strongly recommend the D-70, D-115, D-250 and M-100 tube amplifiers, as they were a huge improvement over all previous ARC tube designs. That series of amplifiers, featured new transformer designs which gave them better frequency response at both ends.
In terms of preamps...I have owned a couple of SP-3 and SP-2 preamps and when compared to the SP-6 series or SP-8 series they sound pretty dated. The SP-6 and SP-8 offered a large improvement in definition over the earlier ARC preamps...the SP-3 and SP-2 were very soft sounding in much the same way as a Marantz 7 preamp sounds. The solid state preamps that ARC built during that time, such as the SP-4, SP-5 and SP-7 are "not bad" but the tube units of that era are much more musical.
Of course, the SP-10 preamp is considered by many to be one of the best preamps ever built and the SP-11 was also a great preamp too.
Hope my input helps on this older posting.
I have owned an SP-3A-1 since 1974, and in 2003 I had it upgraded to an SP-3c. I also own an LS-15. Lately I've gotten the bug to upgrade. I am thinking of selling both, adding a few $, and buying an LS-26 (used). Any thoughts ? Would the LS-26 be a big upgrade from either the SP-3c or the LS-15 ?
Why do member's re-open dead threads that've had no action for over three years?
I've never read the thread before...so it's new to me.