ARC LS1, LS2, LS3 , or LS7, which to buy?

Frap - You nailed it with the rollercoaster effect on ARC's house sound changing from product generation to generation. This too never made any sense as I would have expected to hear refinements from one product to its successor. You had to skip over a few subsequent models to finally get a refined taste of the great past.

I think the use of the 12BH7 tubes was due to a concern for the availability of 6922 tubes. But the huge supply of Sovteks to quickly come relieved this. And the LS5 MK I to II resulted in the use of 10 of these instead of a mix of 12BH7 and 6922. But it did not matter - the LS5 I or II was so phenomenol that how any reviewer could have comdemned and praised the other ARC models made no sense.

I had stocked up a lot of 6DJ8 and 6922 tubes from the SP-10 days so I used these in place of the tubes that the LS5 came with. And now that I know even more how poorly the Sovtek tubes can sound compared to the Teles and Mullards, just imagine how the LS5 might sound fully loaded with Telefunken. WOW! Much of that edgyness on the top would very likely be gone.

I have since learned to try a lot of different tubes in a product before I dismiss it. With 6H30-based products, there's not much you can do here.

Concerning the issue of only being able to use balanced sources with the LS5, I used a single-ended CDP with the LS5 for a few years with great results. Just a simple adaptor with the "-" phase input grounded meant I was only using half the circuit for this source, but it sounded excellent. There was no need to use a bandaid converter box and its associated IC to run such a source. And unfortunately reviewers used these boxes when they evaluated the LS5 with single-ended sources. That was unfortunate .... especially with the mediocre quality of most ICs back at that time.

In hindsight, had I known then what I know now, I would have kept the SP-10 and used it straight into the LS5 from the SP-10's tape out jacks. Someone good with a soldering iron could replace all the caps in this, retube it with the great tubes still available, and drive a state of the art line stage. Maybe with the LS5 II's 30db gain, this could be a killer combination for someone with a <1mv cartridge. And the support for two TT's would be mighty cool.

John

I purchased new a SP9MkIII in 1996, just after manufacture was ceased, and found it utterly reliable - it was in my system until last year. At the time it was compared with the MkII and it was markedly better, especially in regard the phono stage; also the LS7 which, from what I remember, was good but not quite as open and, if anything, more analytic despite having a larger complement of tubes - the store staff seemed to have a soft spot for the MkIII, to the point where, on a visit to Sydney by Bill Johnson in 1997, one asked him whether any were tucked away in the factory, and he offered to construct one from spare parts, which ARC did in fact do! The reviews, professional and informal, seem to favour the MkIII too. I think it should be in your budget. If you listen to vinyl, it really is tremendous.
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I'm sorry but I haven't listened to the LS 1 through 3s. The more recent ones, such as the LS25, sound great, but cost far more. The only one which I would avoid is the LS22, which even the store staff could not recommend.
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As far as SS amps the only one I've tried, and that briefly, was an old Gryphon S100 - terrific, but rare, expensive, only balanced inputs, and not necessarily reliable.
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Good luck.

I will vote for the LS7 also.

(Yes, I know that this is an old thread, but mayme helpful nevertheless...so I dare posting an answer)

Well, I have been owning and auditioning an Audio Research LS2 for about two years.
First it was acoustic heaven (and it is still a very fine, recommended pre), but some day I felt a little discontent , I missed this latest decay, the fading away that only fully tubed (pre)amplifiers are able to produce (IMO).
As I didn't want to spend up to two grands or even more on one of the pricey AR or CJ units, I took AR LS25 and LS22 from my list as well as CJ Classic 2 I have been after for some time.

I finally won an auction for an AR 7 on Ebay, offered by a Greek seller (one of the nicest and most reliable sellers out on Ebay!).
It arrived equipped with NOS tubes Tesla E88CC, one of the best respected and recommended tubes for AR gear, tweaker's first choice. I plugged it in an it worked well. But when I compared it to my LS2 I noticed some lack of bass depth as well as impact and a wooly lower midrange. I changed the phase of the mains but the problem resisted. Cutting the AC cable down to half of the length and installing a rubber mains plug improved everything slightly but I wanted more.

So I started tube rolling and changed to a quad of Tungsram 7DJ8, a tube that worked well in my AR LS2. And this seemed to be the "real thing"! Dynamics improved dramatically, any haze vanished- what a rich, colorful and blooming, spring-loaded sound now! Much more realistic than the LS2, more tubey!
But this is only the beginning as I am going to change the output capacitors and try some other tweaks (the rectifier diodes have already been changed to these recommended on Triode Dick's page). So stay tuned!

Regards,
Jan