Suggestions for Class D amplifiers with Marantz AV7704 and B&W cdm9nt combo for HT.

I have the CDA 250C power amplifier from Class D Audio ...
 
https://classdaudio.com

I use it for music and not movies.  Still enjoy the amp very much.

Rich 

NAD is using Hypex modules in their 7 (or is it 5?) channel amps, worth considering.

Yes, they are very efficient but they still do about 7 watts / channel at idle, and under full load still waste ~10% of heat. Make sure you account for that!

Best,
Erik

Classe Sigma Amp5 and Theta Droughnout class D. 

Thanks to all who have responded.

If given the choice -- Class AB is still the go-to choice? I was looking at the cabinet again - as a Class D choice is not my first choice - and I can install thermo-controlled fans in the cabinet to bring in cooler air and exhaust hot air... or I can leave the doors open during use I guess.

I will check out the amps  you suggested.

I have a Wyred 4 Sound ST-1000 MK2 that I used in my HT setup with a Marantz AV8801 (since replaced by a AV7704) and also for 2 channel (separate preamp with HTBP).  It's a great amp with tons of power, excellent bass control, and a very clean sound. 

I recently replaced it with Rogue Audio M180 monoblocks which have a bit more top end detail and better soundstage.  I felt the W4S amp could go louder with less distortion.

I'm now using the W4S amp in my bedroom system now for home theater and 2 channel through a Jolida Fusion tube preamp and it sounds wonderful.  

The speakers I used it with are Legacy Audio Focus 20/20 and Klipsch KLF-30.  Both very large speakers and very efficient with large woofers.  The W4S amp is an excellent match especially with the KLF-30 speakers which can be "bright" with the wrong amp.  Excellent bass control and a very clean and detailed but not "edgy" or "bright" top end.

The W4S beats all the other amps I've owned (Emotiva, Krell, Rotel, Sunfire, Lexicon, Parasound) except the Rogue monoblocks and if I had to get rid of them I'd be very happy going back to the W4S amp.

Class AB is still the go-to choice? I was looking at the cabinet again - as a Class D choice is not my first choice - and I can install thermo-controlled fans in the cabinet to bring in cooler air and exhaust hot air... or I can leave the doors open during use I guess.

I don't think so, no.

I think we are well past this. Which amp and which speaker matters. My current Class D are far better than a lot of Class A/B amps, and some Class A amps I've heard, some megabucks. 
The amp / speaker integration matters a lot more than which class of amplifier.

The rest is snobbery. 
My suggestion is get a Class D amp you like the sound of, and put a portable digital thermometer there to figure out if you need anything else.

Best,
E

I still love my Wyred4sound SX-500 monos feeding Von Schweikert Speakers. Detailed with natural voices and solid bass, at least in my room. 

I am not into class D and not a fan of it. Class D amps are fine to power surround speakers or Atmos overhead ceiling speakers in a HT setup. I would never use class D amps for stereo music playbacks.
While it’s true that today current class D design amps have come a long way and have improved quite a bit compared to older class D designs from back in a day like some 10 to 15 yrs ago or older, but they are still lacking body, volume, air, midrange bloom, full mid-bass & bass power and overall musicality in comparison to very high quality analog or class A & AB designs IMO. Class D can usually sound leaner thinner lacking body and volume and somewhat analytical and lacking that lush analog sound and don’t sound liquid and fluid as good class A & AB designs. It's true that today modern class D designs have smoother highs compared to older class D designs from back in the day. 

@caphill Class D amps are also analog if I am not mistaken. 

@lightfighter2018 have you considered Hypex NC500 based amps like Nord or Apollon?.

@caphill Class D amps are also analog if I am not mistaken.

Class D amps are binary, but not digital. Weird, right?

They are not "digital" because they lack an Analog to Digital conversion stage, however, the output stage switches between on and off.  The rate at which that switching happens is controlled entirely in the analog stage.

Best,
E

I am very very pleased with my two channel system using a Marantz AV8801 as a preamp to my Bel Canto 500m monoblocks. Also in an enclosed cabinet (Salamander), and I have no worries about heat. Prior to the bel cantos I used adcom and B&K amps (200wpc) and moved to the BCs for the extra power and the heat factor. I think the Marantz and Bel Canto work well together. B My cabling was all Nordost but I did change my speaker cables to Acoustic Zen Holograms for a fuller sound with the BCs. 

@geek101 

 I am not familiar with Apollon.  Have heard of Nord. But know nothing about them. Will check both out.  

@caphill  I admit I don't know as much as others here in A-gon, but as I understand it in the class D space - anemic presentation - is still a byproduct that hasn't been resolved to the same substance and - for lack of a better term - meatiness of  the AB class gear.  As stated - everything is better today even class D. Which makes it all the more difficult for guys like me with limited funds to make a decision that I need to live with for a duration vs changing out gears every few months or years.  And trying to figure out which amp goes with what speakers is a daunting task - albeit - part of the fun of audio. But with the advent of SO many more choices than there were just 15 years ago -- it makes it all the more complex an issue of finding what works and what doesn't.

@erik_squires 

Reliance on the SMEs in A-gon has been very helpful.  So thanks to all who take the time to contribute.

  

@lightfighter2018,

That's what I found with a W4S ST-500mkii. Super clean, authoritative bass, not shrill by any stretch but a lack of meat on the bones. The DAC-2 being used as a pre was probably a bad match for the sound I was after. A tube pre might have sounded better.

Also, Live Dirac room correction focuses images and sharpens the presentation a good deal. This brings out the teeth on every note in a SS pre and class D amp combo. I prefered the older Parasound class A/B. 

@caphill  

lacking body, volume, air, midrange bloom, full mid-bass & bass power and overall musicality in comparison to very high quality analog or class A & AB designs IMO. Class D can usually sound leaner thinner lacking body and volume and somewhat analytical and lacking that lush analog sound and don’t sound liquid and fluid as good class A & AB designs.  

 
Ladking power in the mid-bass/bass is just untrue, they amplify linearly, maybe compared to tube amps. Body, volume, air, and musically are all non-descript terms, stuff like poor channel separation, high noise floor, slow transient response, high distortion, etc. are all more useful. Describing a sound as dry or wet is just nonsense talk, like describing a television’s picture as feminine, it doesn’t mean anything.

lacking body, volume, air, midrange bloom, full mid-bass & bass power and overall musicality in comparison to very high quality analog or class A & AB designs

This is a true thing and most of today's Class D amps will suffer from this lack of bass/midbass and midrange bloom because of their small switching power supplies.  It doesn't matter if the switching power supply can provide 2000 watts of power.  It just will not have the full strong bass/midbass and midrange bloom because of it's small amount of capacitance bank storage.  They just will not be able to compete with large size transformers and large capacitor banks for bloom, power and punch.

That is also why I bring up the ATI Hypex solution.  Because it does use a standard linear power supply with good size transformers and decent capacitance.

In addition, some of these comments were describing older Class D circuits.  The frequency response of these circuits were dictated by the impedance curve of the speaker (where the impedance drops down very low in the bass/midbass area).  Result can be weak bass/midbass and also rolled-off highs.

@erik:
"Class D amps are binary, but not digital. Weird, right?

They are not "digital" because they lack an Analog to Digital conversion stage, however, the output stage switches between on and off. The rate at which that switching happens is controlled entirely in the analog stage."

This is not correct, you cited several misconceptions. The rate of switching by the modulator is fixed, often at 400+kHz. And they are not binary no more than any class AB amp is, they are purely analog. And the output stage does not switch between on and off.

To the OP: please also consider PS Audio’ Stellar line of amplifiers. I have their M700s and they do everything and more that I want. And I have owned Class A, Class AB, in both tubed and solid state formats.

Marantz PM10