Question For Those In The Know About Audio Research Power Amps


I've flirted with ARC gear over the years, owning an LS5 preamp some years ago but never trying their power amps.

I've always had the idea that ARC tube power was a little lean and sterile and not in the Conrad Johnson style of presentation, with tube bloominess and that glorious CJ midrange.

Of course, I realize not all ARC amps sound the same and that some are warmer and more tube-like than others.

Anyway, I recently purchased an ARC Reference 110 SE, and really like a lot about what it does. Stage depth and imaging are excellent, it's detailed and dynamic. As if to reinforce the negative stereotype, it is a little on the lean side, but not horribly so. It's a musical amp overall, and that's what counts.

Questions -
1 - this was sold to me as a "SE" model, which I understood to mean that it was modified to allow the use of KT150's, which my amp has. Was this an 'official' factory modification, and if so, is the SE designation something which can be used when I try to resell the amp? I can't seem to find others running KT150's referring to their amp as the 'SE'. Or is the SE designation relating to a different upgrade altogether? 

2 - is this 'SE' amp backwards compatible with any other tube types?

2 - what's the next model up from the Ref 110 that might exhibit a little more tube bloom (warmth) than the  Ref 110? I wouldn't want to lose the wonderful transparency and soundstage ability of this unit, but if it could be fleshed out a little more then that would be a plus. The amp is only a couple weeks old, to me, so I'm still trying cables and supports etc, to see if there's more to be had, but I would say at this stage that this is a pretty amazing amp.

Any insights would be appreciated!

Thanks
Rooze

128x128rooze
@minorl -thanks for correcting me on the vintage of this amp as it relates to warranty coverage. I'm obviously not up to speed on current or even recent models--- I was a long time ARC customer in the early days, from the SP-3-a-1 up through the SP 10mk ii and the last amp of theirs I owned was the Classic 60. I still have my Dual 75a that I bought new back in the mid-'70s. (It needs a go-over before I'd power it up again). Back in the day, ARC was terrific on service, parts and updates. 
Hi Rooze:
I was in the same boat as you. I had a Ref 110 and loved it but found it a little bit on the lean side. I thought that might be the price for the ARC bloom and holographic presentation. When I purchased the Ref 150--that all changed. Now there was meat on the bone. Images had more substance but without any loss of the other ARC attributes.That was exactly what I had been looking for.
With a  helpful word from the "inside" at ARC, I replaced the stock KT 120s with KT 150s and that was another slight foot forward (although not nearly of the magnitude of the difference between the Ref 110 and the Ref 150). A move to the Ref 150, Ref 150SE or GS150 from the Ref 110 will provide what you are looking for.
BTW, you cannot put KT150s in the Ref 110.
Well, you didn't mention what you paid and that isn't necessary, but you did get a tube upgrade.  Those 150s are about a $600 upgrade over 120s and even more $ over the 6550s.  You definitely got an 'upgraded' amp, but the use of 'SE' was wrong.  Have you spoken with your dealer?  Many are crucifying this guy and it would be nice to get their response to the situation.  Most have probably not heard a REF110 with 150s so your sound is pretty unique and maybe less 'lean' than what any others are sharing from their experience with the stock tube choices.  I have Classic 120s so have only heard 6550s.  I have a friend that has heard many ARC amps and recently added a REF75 to his system with the KT120s and he has been blown away at what those 4 tubes can put out.  I can only imagine the REF150 is better but you lose the cool blue meters.  I really don't think you can go wrong with the REF 75, 150 or 250 series of amps.  These were all introduced 8-9 years ago and are still in production which says a lot.     

@dhite,

Not sure where your getting your info but all the REF's you mention are NOT still in production nor have they all been for quite some time now. Even the REF10 Pre Amp hasn't been produced in over 9 months now.

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