Comments please on: NAD M23 vs c298 vs. other newer Class D

@atmasphere I’d love to hear your response, also.

I sometimes wonder – not about Atmasphere but generally – about products that incorporate features meant to convey "serious equipment" to buyers using what implementations that are really cosmetic, not functional. We see this all the time in products; engineers and marketers dream up the product together. The question becomes, does this ever happen with mono designs? In other words, are there some products where something is made "mono" mostly to fluff customer expectations rather than electronic and sonic priorities? How would a layperson figure that out?

If Class-D amps can be carefully laid out in a stereo two channel format with "plenty of power", relatively low distortion, with careful isolation of components for each channel, in a shared chassis - what would be the Top3 reasons some manufacturers still choose to make Class-D amps as mono amps?

@decooney @hilde45 The main reason is to reduce colorations.

Mono amps insure there is less noise in their power supplies and allow you to place the amp right by the speaker, thus keeping the speaker cable as short as possible. The reason that is important is no speaker cable is really correct; they all have mismatches with the speaker. Your best bet to minimize those errors is to keep the speaker cable as short as possible.

That is also the reason we use a balanced input. If your preamp supports the balanced standards then the interconnect cable's artifact (the reason interconnect cables can be really expensive) is minimized or non-existent. As an example I run 35 feet of interconnect cable at home and often at audio shows too. 

So that allows for the least coloration; something that is a lot harder if a stereo amp is used. 

Thank you, Ralph!

My WT amp ultra (upgraded Wiim amp) is only $1300. It sounds clean and musical. Compare their sounds below. Alex/Wavetouch audio

The sound of  NAD C298

The sound WT amp ultra

WT amp ultra

"@atmasphere So that allows for the least coloration; something that is a lot harder if a stereo amp is used."

Thanks Ralph for your explanation.  On a related topic, something I’ve come across in many reviews about different Class-D amps [over the past two years] has to do with a particular explanation describing how the sound can be somewhat "blurred" or "co-mingled / blended" together more so between the left and right channels. As I recall, most were Class-D stereo amps vs individual mono amps for each channel. 

For my own reference, some of my lower quality Class AB solid state stereo amps do this, yet my pure Class A solid state amps is a bit better at channel separation, not as blurred together. However, my monoblock tube amps keep it all well separated, and distinct between the instruments in a very distinctive way. 

Admittedly, I’ve not tried any known high quality Class D mono amplifiers yet. I may try this some day when it becomes a compelling "no brainer" to do it. 

ASK:

We get it that you are an engineer. Here is the curve ball question about the "sound". When you compare your own Atma-Sphere TUBE amplifiers to your new Class-D mono amplifiers, what can you share about the sound - What is similar and what is different about the sound stage, depth, placement of the singers voice (more forward or back), and what about channel separation and instrument separation. 

What is similar, what is different, comparing the sound between your Tube vs. Class D amps?