Amplifier suggestions to drive a pair of NHT 3.3

Hello Audiogoners.

I recently aquired a pair of used NHT 3.3 and I'm pretty happy about it. I intend to build my 2 channels system around them. So, the rest of my gear will probably be all upgraded at one point or another.

For the moment (this fall-winter)I want to upgrade the power amp. I got a Rotel RB-956AX, I bi-amp, bi-cable with 50w/c. No need to tell me how much I miss with this amp, it's pretty obvious to me...

So, I want decent power (200-300w/c) in a 2 channels unit (monoblocks while tempting will be avoided for the moment). I want deep thight bass, warm mids and sweet highs (don't we all).

I'm considering:

Mark Levinson 23.5
McIntosh MC300-MC352
Pass Labs X250-X350
Krell KSA200S-FPB200
Classe CA300
Bryston 4B-SST

So in the range of $2000 to $3000 used.

Any comments on these amps (or others) with the NHT 3.3 mostly appreciated.
Haven't used any of your suggested amps, but have used NAD Silverline 200, B&K M200 Sonata Mono's, B&K Refrence 4420, Adcom 555 II, Parasound, Rotel and a Krell integrated. I recently purchased two Threshold amps, a recently upgraded S 150 II and an original S300 II. Although, I have a smaller room (soon to change) and many a folk comment on the NHT needing lots of power, my little Threshold is simply amazing with the 3.3's. Incredible air and deep tight bass when called for. I'm sure any of the suggested would be great. Not sure if this helps, but my 2 cents worth. Just sold the Threshold S300 II.
I used an Aragon 8008BB with great success on those speakers. I just never saw the need to spend more...great amp.
Classe, based on the fact that User510 at the Analog Dept runs their small integrated with his NHT 2.9s.
Classe 700s woked very well. Great bass control. Watch out for the treble for the tizzy spits. Good luck.
Bi-amp them with an active crossover on the bottom it really opens up the NHT's. On the high end of your range I used an EAD Powermaster 2000 5 channel (400watts x5) to biamp the NHT through an active crossover (actually my EAD Signature processor) and used the spare channel for the center Aerial Center Channel! Amazing results and a more liquid top end then the Aragon suggested above (Aragon would work nice for the bottom since they are a real workhorse).

If I remember correctly the bottom was crossed over at 100hz.
Corey Greenberg formerly of Stereophile and Michael Fremer formerly of the Absolute Sound used the 3.3's as their reference speakers for a time when with these respective magazines ... I believe both used the Aragon 4004mk II as the partnering amp
Corey was great. Wonder what he's up to these days?
Thank you all for your comments and sugestions.

Anyone else with some experience with the 3.3 and the amps I'm considering or any other(s), feel free to post your comments.

Thank you.
The Odyssey Stratos Dual Mono (2 monoblocks in one chassis) would be a very good match with these speakers. And they would also save you some money too. 20 year warranty.
I am using Aragon 8008 Mk2 to drive 3.3 and I feel 3.3 might like more power. I am thinking about a Classe CA 300/400 or Krell KSA-250/300s. Suggestion?

Roy2001 - I used a 8008BB with great results on those speakers. That's a very powerful amp you have (more like 300wpc at 8) .If you truly want perceptibly more power than what you've got you're into Krell FPB-600 land. Maybe it's just a different sound you're looking for.
I just can't believe anybody telling they need more power than the Aragon.
I think if you're driving an old pair of 3.3's you migt want to replace the crossover network, talk to NHT about it, , , , more power.
The Aragon puts out 300 real watts at 6 ohm (NHT 3.3 are 7 ohm load) and they trally feel a lot more powerful than the 400 WPC compared to Sunfire and other ampl opn that class.
If you really want more power buy the Threshold Audio Version Monoblock or the S-5000e released a couple of year ago retails for $2,600 or so.
Maybe you can find a used one around.
I have been driving my 3.3's with am Aragon 4004 MK0II with much success, also using noe the Threshold S-5000e, more livelier than the Aragon, more air on the top end which the 3.3's do wonderfully,
Sunfire cinema grand biamping lows and top (2 channels per speaker) did not quite do it, didn't feel like the Aragon or the Threshold.
You might want to try a Krell KSA 250 or somethind like that, not more power just different flavor.
By all means replace the crossover network if you have an older pair 1993 to 1997 or so.

Hope this helps a little

God Bless!

Thank you all for your imputs.

Well, because of some changes in my life I had to reduce the budget available for my amp (for the moment).

I opted for less power but a lot of music and finesse (and a decent bass!).

I bought a used KRELL KSA-50S .

I Gotta say that I'm amazed each time I listen to some music! :)


When you suggest to replace the crossover network, do you mean to replace all the caps ? If so, did you replace them by film caps or electrolitycs ?

I use a B&K ST-202+ (300watts at 4 ohms) FET output transistors provide a warm tube-like sound. When I was a kid I heard Ginger Baker play several drum solos in a small club. When I play his Cream rendition of his Toad solo I am still floored by it on the 3.3's. They are great all-rounders but the bass is magnificent. As for the rough highs I replaced the tweeters with superior Seas Excel t25cf001's and they made the top end softer and more life-like to my ears. Electronically they are pretty close to a drop in so I didn't change the XO but a little Dremel tool work was needed and the flange overlaps a little but still looks good. I like them a lot better now.
Just bought a Crown xls2500 because of good net reports on it and others in various blogs on their drivecore series. I used it to replace an excellent B&K 202+.

Cost new under $600 from local Guitar Center with a free return policy. Less on Ebay.

Result fantastic sound. Can hardly believe it isn't a $12000 Class A amplifier. No white noise even with my ears next to the tweeters and I can't hear the fan even when it comes on and I'm next to it.

I have never before heard such well controlled bass and sweet highs coming in combination from a solid state amplifier into none set speakers. The sound is neutral and flat with no coloration. I loved my B&K's but I have to believe my ears more than my prejudice against pro-audio gear. Check them out, they drive over 400wrms per channel into 8 ohms and almost twice that into 4 or 2
I just stumbled on your post, I LOVE CROWN amps I am Bi-amping a pair of NHT 2.9s with a 350wpc Crown K1 on bottom and Parasound 220Wpc on top, super clean an lots of headroom. An audio engineer buddy of mine swears by Crown and says they are the cleanest of all the pro stuff for the money ( he also has perfect pitch) Enjoy!
No need to Bi-amp with the xls2500 440 watts per channel into 8 ohms and almost 800 into 4. I did bi-wire however. Yours is a good set up though as that Parasound has a good rep. I don't know anything about the K1 though but its a Crown. The XLS2500 Crown drivecore is actually a class d amp but has some amazing specs and probably sounds as good as any of the best money can buy on the NHT 3.3's due to their 6 ohm load and 4.3 ohm dips. I can't hear the fan or any white noise. I'm sure it isn't a good amp for very efficient speakers as the A weighted S/N of 103 db is probably too much for 100 db + speakers but the 2.9 and anything below 92 db should be no problem IMHO. As for distortion there isn't much in the range we can drive them at (yes even with the very loud 3.3) They sound neutral and very clean with a very flat response across all frequency and power levels. Its quite extraordinary for the price and I've been at it since I built my first kit amp over 50 years ago. The xls2500 weights 10.8 lbs and has built in filters and even a special AC power neutralizer too as well as being very efficient. A lower power XLS Drivecore would have done but I wanted the biggest sweet spot I could get as all amps distort their worst toward full power which I never reach due to built is clipping limiters, huge power capability and being able to set the input gain levels so it never clips too.
Actually spinster after after looking up your Crown K1 amps
specs I really think it should work better alone driving the your NHT's as it should be a better amp than the older Parasounds in almost all respects. Did you try it by itself? The S/N is a little higher than most newer amps but that shouldn't matter much with 2.9's and the other specs and power range are excellent. Please try it and let me know? It might not sound as tube like as the Parasound but it should be flatter and clearer across the whole frequency,power range:
KI Performance
Frequency Response: ±0.25 dB from 20 Hz to
20 kHz. The frequency response is band limited
with an 8 Hz double-integrated 3rd-order Butterworth
high-pass fi lter and a 30 kHz 7th-order
Gaussian low-pass fi lter.
Signal to Noise (A-weighted): > 100 dB below
rated power.
Damping Factor: > 3,000 from 10 to 400 Hz.