Audio Research pre amp question

I'm about to venture into tubes for the first time. I have decided after trying out a AR VT 100 MKIII, that I am ready to give it a go. Even though I was using my exsisting solid state pre amp I still felt the thrill. I put on a Suzanne Ciani & the piano sounded so real. I have played this CD possible a hundered times & it was as if I was hearing it for the first time.

My question is which AR pre? I've read about the LS MKI, LS MII ( I understand a new tube is used) & the RM 25 MKII. The Reference 2 is not a consideration, not in the budget.

Some of my thoughts: Will the LS Mark II give me 80% of what the RM 25 MKII can do? Is the RM 25 MKII the only way to go if it in the budget? Does listening preferences dictate which unit to consider? Just don't know enough about these to make a decision.

Here's personal info: I listen to a lot of female vocals, blues, classic rock, country when I feel like it & a few specific jazz artist.

If you have any first hand experience with any of the AR pre's matched up with AR amps please share your knowledge.


I am using an ARC SP9 MKII, ARC VT60 combo and it is really a beautiful thing. As for other combinations, I have no experience. I hope that this is some help.
Ron, you'd better tell the folks which LS model number you're talking about, they start with the LS1 and move up from there! Of the LS series, my personal favorite is the old LS5, which to my ears was the least solid-state sounding of ARC's line stages (other than the less-refined, entry level LS7) and should be a very good match for the VT 100. Check the archives, there are a lot of happy LS5 owners who discuss the different marks of that model.
Sorry -- I am refering to the LS 16 MKI & II
Very good advice from Rcprince. The LS5 has the musical magic, harmonic richness, natural decays, etc., that no other LS series before it ever had. And the LS15, LS22 did not have it either. I suspect the LS16 is the same way as it was a tweaked 15. You have to go all the way back to the SP-10 to get this. And I suspect if you are a piano and female vocals diehard, the LS5 is your ticket if you want to stay in the ARC line. Try to find a MK III as it has a more balanced tonality, i.e., not the added sibilance of the MK II/I.

Correct me if I am wrong, but isn't the LS-5 the preamp that only had balanced inputs and outputs? Therefore, if you are not running balanced cables, you will need to buy them, and if your equipment is not setup to run balanced, you will have to replace that as well.

From my research into ARC preamps (and I own an older LS-2), I have formed the following opinions:

A.) The LS-16 is a good preamp, but not a whole lot better than the other LS series preamps before it, (and not much worse than the subsequent LS-22). (With one exception: The LS-5 which was reputed to be very good.)

B.) The LS-25, Mk II is a very good preamp. This will sound about as good as the LS-5, but it has more bells and whistles.

C.) The Reference II (Not the original Reference though, which was a glorified LS-25), supposedly sounds better than all the previous ARC preamps. (I have a friend with this preamp, and combined with his Avalon Eidolons and his 400W/ch Classe amp, it produces the finest sound I have ever heard from a stereo system.)

BTW, my choice, when I get the cash, someday, will be to upgrade to an used LS-25, Mk II. I want to have the sound of the LS-5, with the bells and whistles of a modern design, without having to take out a second mortgage on the house! (Plus the option of not having to run balanced inputs. I run balanced out, but my phono preamp, and my other equipment is just not setup to run balanced cables unfortunately.)

These are my opinions, so don't start a flame war.

Good Luck in your search!

I have a VT 100MKIII and just changed from an LS16 MKII to an LS 25 MKII. The 25 provides MUCH more detail.

By the way, with these components, you should consider balanced operation as mandatory: I have seen the schematics, and if you run them SE, you are basically throwing away half of the circuitry. They are designed as balanced.

I did a comparision of SE vs. balanced, and it was not contest, even with fairly short IC runs.

Have fun,

I have a LS-16 and a LS-25 and I like female vocals and piano music . I don't hear a big difference in the two pre-amps . I did notice quite a difference in the LS-15 and the LS-16 and from what I understand there was quite design defference in those. If there is a difference in the LS-25 and the LS-16 it is that the LS-25 has more detail and bottom end , but the systems are different that I use them in so of course that makes a difference also. I'm using the LS-16 with a 300-B amp and the LS-25 with Ultra-linear tube amp. Now you have my two cents worth.
Yes, the LS5 is the only preamp (line stage) in ARC history other than the PH2 phono stage, that has ONLY balanced inputs and outputs. Both of these models were the first to have truly matched balanced circuits in the ARC line. Models like the LS2B or LS3B had XLR connections but were single ended designs. The LS5 and PH2 came at the end of the end of the Classic and V series amps that then phased into the outstanding balanced-inputs-only amps, VT130 & VT150. Later ARC came out with the LS22 and then LS15, Ref1, models that had all sorts of inputs and outputs. The LS5 MK III followed from the Ref1's design and to many of us who heard these two models, the LS5 III was prefered. It simply had more of the midrange bloom and 3D. But all of the LS5 versions have this quality. I simply do not see the value for the Ref1 in the $4k range on the used market. So much can be gotten now for $4k that brings on so much beyond the Ref1 now.

After 7 years with 3 LS5's, I was ready for a change and the BAT 31SE was a natural progression for me. But the LS5 and PH2 will always be remembered as components in my system that brought years and years of musical enjoyment. These paired with the VT130 amp were an incredible synergy .... wow, awesome midrange bloom and harmonic richness. I then switched to an older pair of ARC Classic 150 amps in hopes of more power for my Magnepan 3.3s, and indeed I got a little more headroom, but much of that special quality of the VT130 was gone.

The PH2 especially is a killer phono stage if you are willing to put up with the balanced connections as well. It is perhaps the most neutral product ever in the ARC line.

I did hear the LS25 and the presentation was quite nice at the ARC dealer, but I never had a chance to do a shootout with this at the dealer or at home vs the LS5 III or BAT 31SE. Just stay clear of the LS2 and the Atmasphere MP3 as these are not in the same league. Lots to learn if you take the time to listen and compare. And if you do not get too attached to any product line, you can often get so much more ... and for less money.
I have owned LS-25mk1's since they came out. Warm, musical, great soundstage- yet dynamic, transparent and detailed (with right tubes) all in the same package. Performs best when mated to an ARC amp. Will never sound solid state like when matched this way. Used with a less than ideal impedance match things change drastically. I'm using it with the new ARC 150.2-- can you say Holographic soundstage!
I'll second the LS5 - I have the mkii version
I have owned the LS2 and it is hard and grainy on the top end. I have done demos of the LS22 and 25 and ref1 on my home system - the ls 5 is clearly much more open, vibrant and engaging, no contest and well worth the extra money. You would have to go up to the ref 2 or the Bat pre Jfox suggests.

THe balanced inputs are no problem, I use a ph2 so I am balanced on my phono stage. I use adapter plugs on my cd front end and dvd player.

As for tubes - some nos telefunken's really make this preamp sound fabulous - check out fletch here on audiogon for the best vintage tubes, he sure did my system some good
As I had hoped to receive, great informative responses from all of you & thanks. I felt that anyone owning ARC products would be serious about there music. I am running balanced so the LS 5 would be no problem. At this point I am going to seek out the LS 5 & the 25. As to which series I or II depends on what is available to listen to with the rest of my components; at that point I'll let my ear's be the judge & pick one.
there are 3 LS 5's (mk I, II, and III) listed on audiogon

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