What is a good amp that cost no more then 3500.00

You should spend $2000 on an amp and use the other $1500 to buy a good used preamp, you definitely need to upgrade from Yamaha. Maybe a good solid state amp like an Ayre or M-L, or BAT, and a tubed preamp such as a BAT 51.

Buy a musical fidelity M3 integrated it kills every amp here except the pass x250 maybe and it has a lot more power and a really good preamp to boot. Lastly it is much much better than the A3cr, believe me i've owned both.

I second the CJ suggestion if you want to give tubes a try. I have Response 2.5's and use Premier 12's with it and I think it sounds fabulous. They're also known to pair well with ARC amps (either VT100 or 100.2), and I've heard them sound very good with Cary. A used CJ Premier 11a (~50w into the ProAc's) will run between $1500 and $2000, and Premier 12's (~100w) between $3500-$4000. Keep in mind that power isn't necessarily the most important factor as long as the amp is capable of driving the speakers. Tube equipment tends to clip more softly than SS, and so can be driven a bit harder than their SS counterparts and still sound good.

One caveat is that the ProAc's have a pronounced bottom end which can end up being a bit overpowering in a smallish room with a warmer amp (which is what I experience in a 15' x 20' room). However, these speakers simply sing when driven by tubes and I'd give serious thought towards leaning in this direction.

You might try a Bryston 4BST. 250 watts into 8 ohms,
20 year warranty. You can sell it w/5 years left..
If it sounds a little forward in your system, try a Pass
X250. The Pass is more laid back, but it will heat your listening room up....

Daniel

hello the Yamaha has got to go. Invest in a preamp a placette passive is awesome for the price. I concur with the Conrad Johnson premier 11 amplifiers also.