Without knowing your speakers, I can offer suggestions of a Krell FPB600 or a Plinius SA250. Both amps can have a slight softness in the highs, which would help for what I assume is an over-aggressive response in the highs with the Wyred4Sound. (Correct me if I'm wrong about your complaints about the highs in your current system.)
Coda Model 15
Spread Spectrum Technologies Ampzilla/Son of Ampzilla
Pass Labs XA30.5
Pass Labs XA60.5
The speakers are Montana XP and it's not that the highs are overbearing, but the Class D amp has limited trailing decay of cymbals and stuff like that.
Not strictly an ESL only amp the Magtech is available for a 30 day trial.
Not exactly plug and play, a Bruno Putzeys design. Hypex restricted power supply (350W @ 8 ohms) in the DIY offering, but far more intriguing design than most current class D. These component modules should soon be making their way into higher powered designs from other amplifier marks (Channel Islands?). Some initial DIY reviews claiming a huge sonic leap forward in switching amplification.
I would look to either Pass or McCormack both provide ss designs that are very musical. I would stay away from tubes unless you are willing to put up with the heat and maintenance issues along with the expense.
You're already used to having a lot of power, so I second Sufentanil's call for big brawny amps like the Krell 600 watters or the Plinius SA 250 - the small and expensive Pass Class xa series amps are beautiful in smaller applications but just aren't going to give you the volume you're used to. Don't know what ARC gear you are looking at, but Modwright doesn't make anything I'd use in a room that size.
Other Plinius possibilities that pop up for sale here with some frequency are the SB300 or SB301. I use the latter to drive Revel Salon 2s in a nearly 6,000 c.f. room, and it has a nice decay with good detail without sounding clinical or cold. The earlier model SB300 is essentially the same as the SB301 with some cosmetic differences and there's currently one listed for under $4K, and also an SB301 for $5K.
With your budgeted amount and willingness to buy used you're actually very well-positioned to make a serious upgrade. Just a few of the other possibilities available here in that price range are a Mark Levinson 532H for just over $6K (I auditioned my Salon 2s with that amp and really preferred the Plinius, but they are detailed), a Pass x350.5 that would fill that big room of yours nicely, a pair of the aforementioned Krell FPB600 monoblocks for just under $6K, a Krell Evolution 302 for just under $6k, etc. etc. etc. Happy hunting!
I have the same speakers --- at least by brand (Montana EPS2's in my case). I highly recommend the Ayon Spirit 3 --- which can be had for well, well below your price range. I have that amp and it sounds amazing on my Montana speakers. Or... if you really want to spend more money than you need... go up a level in the Ayon line.
Another suggestion is by an amp from Montana --- those amps are made for your speakers by the very man who made your speakers... Peter Norbeak.
What about a Moscode 402Au;in home trial period and also able to roll different tubes if you likeand should have plenty of power.
Although you have been warned away from tubes, what has finally done it for me is a VAC PA 35.35 push-pull EL 34 amp. I purchased it here on A'gon, and have recently sent it back to the factory for an upgrade.
Even before the upgrade, this 35Wpc amp had more dynamic power, detail, and resoulution than my Plinius SA 100 MKIII. After the upgrade, it is by far the best sounding amp I've had yet, in 40 years. Tube rolling helped quite a bit as well. The VAC is not big on watts, but its ability to provide large amounts of current, gives it enough oomph to do an outstanding job. My speakers are in the 90db sensibility.
All this superb performance cost about $2200. Quite reasonable, in my opinion. Best of luck with your decision, and whatever you wind up with, I hope you enjoy it.
Vic... DIY is not really for me. I'm more of a LSEDI kind of guy. (Let Someone Else Do It) I'm just not certain of my power requirements. I was able to audition a Class A 30 watt (Belles SA30) and it seemed to be on the lower edge of power output required. The Pass XA30.5 does put out a bit more as it slides into AB so that may be the answer. The Coda 15.0 seems best, but it's probably a room heater and idles at about 700 watts.
Go for a great hybrid amp for the great sound of tubes without the hassle and heat. The Aesthetix Atlas stereo amp is wonderful as is the Moscode.
What do you guys think of the ARC HD220 hybrid amp? That was the ARC model I was thinking of in original post. I have read the Audiogon review where the guy loved it and then 4 months later didn't, but I suspect he is a true "tuber" and embraced the added dynamics and assumed clarity for a short time only.
I have a Montana EPS2 and Pass INT-30A combo, which I like very much (it certainly has sweet mids/highs), but I suspect the pass 30s would be light on thump in your room. A lot of people around here have said the 60s are not hugely different than the 30s, which suggests the 100s, but I'm guessing they are out of price range, even used. (Mark at Reno hifi a great resource for Pass, btw).
As Robsker notes, I think it is worth calling Peter at PBN. I think he sometimes has deals on his amps, and he is a good guy to talk to; I suspect you could hit your pricepoint. Interestingly, Peter builds big A/B amps for his speakers, which is some evidence it might be the way to go. I ran my EPS2s with a big Odyssey, and while I prefer the Pass (as I ought, for the price difference), I miss the authority on the lows.
Let us know what you do.
I've been switching back and forth between the ICE amp and a Cary SLI-80 integrated. They both have virtues the other one doesn't. This is probably an age old question that has been asked and answered a million times. I think I'm wasting your time. Thanks for all the responses, but I have to audition more amps in my system to get my answer. I should have known this from the start. Thanks again.
The Aesthetix Atlas Stereo is a high powered hybrid amp that you might want to check out. Not only is it -IMHO- a fine sounding high output power amp, it's also unusually flexible in that it includes a very versatile low cut x-over function should you ever choose to bi amp.
IIRC, it's +/- $8k new, so a used piece (if you can find one) probably lands in your price range.
Thanks everyone, I will report back, but it may be a while as getting amps to audition in my home is not an easy task, especially since I want to get one used.
McCormack DNA-750 monoamps. About $5K NEW. 900 Watts (continuous) in 4 Ohms.
for a review of the predecessor DNA-500.
for my experience with a pair.
Koestner I use the Coda 15.0 about 9-12 hours a day.
It barely gets warm.