I am in the market for a $ 5-6 k monoblock amplif

The OP posted in 2011, so it's unlikely they are still looking for an amp... BUT, I will second the recommendation for Merrill Audio.  I picked up a pair of Thor mono's and was completely blown away when I first heard them.  While these are my first class d amps, I've owned amps of various topologies in the past - atma-sphere, vac, pass labs, McIntosh, Levinson, etc, etc - and feel that the Merrill amps are not 'great for class d' they are simply great amps period.  Very highly recommended.

I absolutely love my Bel Canto ref 500Ms. I have had them for four years or so, having graduated from powerful older solid state amps (b&k and adcom) .  I've always been happier with more, rather than less power.  Anyway, the class d bel cantos are wonderful--warm and musical and I haven't grown tired of them at all.  In your price range, the newer Ref 600Ms are supposed to be even better.  Red the reviews.

best of luck,
tom

Class D is a good choice, look at Merrill Audio and do a search on their THOR monoblocks, can't go wrong IMHO.

I suggest you look at the Hypex Ncore NC400 Bridged Monoblock CLASS D Power Amplifiers.  The cost for this model is $2,980 plus shipping. 

I purchased the Hypex NCore Class D amps from James Romeyn Music and Audio, LLC (James). He was very helpful answering my many questions and I suggest you contact him for more information on his assembled Hypex amplifiers (he offers 3 models). Please see:

http://jamesromeyn.com/old-pages/home-audio-gear/hypex-ncore-nc400-build-service-on-time-or-free-bui...

Choose from Three Hypex Amplifiers

1. Stereo powered by Hypex SMPS1200A400, 600W @ 2 Ohm, 1 Ohm minimum, $1,490/each, 1200W Hypex power supply for 600Wpc, dimensions 2.8″ x 9.8″ x 12″ (70 x 250 x 308mm), 8.5 lbs (3.9 Kg), specify face plate finish: black or natural aluminum. 

2. Bridged Mono Bloc powered by SMPS1200A400, 1200W @ 2 Ohms, 1 Ohm minimum, $2,980/pair, 1200W Hypex power supply, dimensions 2.8″ x 9.8″ x 12″ (70 x 250 x 308mm), 8.5 lbs (3.9 Kg), specify face plate finish: black or natural aluminum.  I own this model.

3. Regular Mono Block powered by Hypex SMPS600, $1,900/pair, 600W power supply, specify faceplate finish: plain black, black with NCore logo, plain natural aluminum.

This is my first class D power amplifier and, based on my results, sounds terrific.  I am thrilled with how good my system sounds.  I am hearing details, imaging and bass that I have not heard before.  Of course, everyone has a different opinion on this subject.  You never know “how it really sounds”, until you listen in your room and audio system.

NOTES:   I am using the Bricasti volume control and do not have a pre-amplifer in my system.  We adjusted the Hypex NCore NC400 mono-block power amplifiers so that it accepts a higher incoming signal meaning I can move my Bricasti M1 SE DAC volume control closer to zero.  After conversations with Bricasti, Hypex and James (James Romeyn Music and Audio, LLC), we decided to remove the R141 (circuit) from my Hypex NCore NC400 bridged mono blocks, thus lowering gain by 14 dB, requiring 14 dB higher M1 volume setting for same playback level.  This is more complicated than I expected but it solves the problem.  When you connect the Bricasti M1 DAC to a power amplifier, you have to balance the M1 DAC to the power amplifier in order to achieve your M1 volume settings CLOSE to 0db.   

+3 on the Rogue Audios especially, if you're looking for a tube sound.  Fantastic sound in that price range, you need to really take a listen.  If you're looking for a SS amp, I would put the Parasound JC1 and Hegel H20 on your list.  

You don't indicate how much power you want. Monarchy Audio has 2 hybrid monoamps that are just below or in your range. Both use either* a 12AT7 or 6922** for Voltage gain, a bunch of MOSFETS for output devices, and NO negative feedback, global or local. The SE-160s sell (direct) for $2400/pr. and are rated at 160Watts into 8 or 320 into 4. The SE-250s are more expensive and more powerful.

Monarchyaudio.com. Owner's name is CC Poon.

After auditioning a pair of his smaller amps, I just ordered a pair of 160s for my 89dB-sensitive Audio Physic Avanti IIIs. The smaller amps sounded great; I wanted a warmer tonal balance and more power.

* apparently the owner is transitioning from the 6922 (et al) to the 12AT7, and since these amps are made to order, you get a choice.

** 6922, 6DJ8, 6CG7, 6FQ7, 6N1P, etc.
.

Markwatkiss,

I just built Hypex UCD400HG with HXR monoblocks using Neotech wire, a Furutech IEC & Furutech RCAs and I must tell you that it has bettered my Berning ZH270 significantly in all areas. There is not one area that my Berning is better. It isn't even close to put it mildly. And if you do a search, I think you will find the Berning is a very highly regarded amp.

IMHO, Class D has most definitely arrived and it body-slammed my Berning.

Class D is still evolving and in my opinion the currrent menagarie of Class D amps will not bring long term satisfaction.

If you are looking at tubes, consider Manley Snappers, but you would need to order before February 15 when they are subject to a HUGE price increase.

If you are looking at class D, I might suggest looking at Red Dragon Audio. They offer ICE amps for $499 or $799 each that should fit the bill. The $799 amps are virtually identical to the old Bel Canto Ref1000. Red Dragon offers a return period as well, so there's no real risk. While I'm not knocking the ML Source (by all accounts, a very nice speaker), I'm not sure that I would spend $6K on a speaker that Audio Advisor is selling for $1400/pr. Of course, I've been told the same thing about spending an equivalent amount on monoblocks for my Zu's :)

Seriously, though, try Red Dragon. I conversed with them over the holidays. Very nice and very responsive. A pair of the 500 watt monoblocks should work extremely well for your application (probably at least as well if not better than the 1000 watt monoblocks). That leaves a lot of scratch left over to spend on a pre or a source.

PMB

PMB

I would likely buy the Clayton M200 or M300 Class A mono amps to drive thius electrostatic speaker. Maybe if you peruse the used equipment areas you can find them in this price range.

Greg

I second the Rogue M-150 (used about $2,400) or preferrably the M-180 (about $1,100 to upgrade M150's). I used the M-150 and about a year ago upgraded to M-180 with the Logan Summits. I am very pleased with the combo. I would consider saving some money on amps and use it to move up the Logan speaker line.

I have the Herron M1 Monos and they're fantastic. There are individuals on this board that use them with their ML with fantastic results. Give them a try and you will not be disappointed!

Get some Wolcotts (on used market)....killer on stats. Do some research on them.

Rogue Audio M-150 or M-180. 4 x KT88, 2 x 12AU7, 1 x 12AX7 per amp. KT90s are used for the M-180.

Check out the Stereophile review, though I think the reviewer goes a bit far in his comparison to SS amps. The Rogues have the silky top and dimensionality that one looks for in a tube amp, but also have excellent bass control.

The specs on ML's site seem to indicate that the Source would be fine these amps.

"5 Ohms, 1.6 @ 20kHz. Compatible with 4, 6, or 8 Ohm rated amplifiers."

Hello

I love my VAC amps with ML Aerius speakers. I have the PA 90 D @ 100+ watts channel. Have had this setup for quite some time. Both companies great to deal with, regardless of the questions. Hope that this helps.
Educ

I use tubes almost all the time, but for stats, I think you need much more instantaneous amperage. Thus you might want to look at "Sanders Sound Systems" which makes amps directly geared for ESLs. I would check them out and he is exactly in your price range. I would also investigate the highly regarded "Wyred 4 Sound" amps which are said to be a little warm and as good as many tube amps. Not sure any SS amp really images as well as good as good tube amps do, but Six Moons thought they did.