Theta Prometheus Monoblock vs Bryston 7BSST2

"George, which amps have you experienced which are the audible cause of your pessimism?"

Many and they all have the same trait, explained below.

Until the future technology gives us higher switching frequency, we'll get this (linked) switching frequency noise on the top of the square wave in pic 2 and that's at 1khz!!!
At 10khz (not shown) it's 10 x worse (if this was a linear amp, you'd say it was broken)
And the output filter is already started to roll the audio frequency off at 10khz to try to minimize it Pic 1.

http://www.stereophile.com/content/theta-digital-prometheus-monoblock-power-amplifier-measurements#d5BMlUSvHXmmeEbA.97

Today we have two detrimental ways to get rid of the Class D switching noise, with output filters on these amps.

1: The filter to roll off earlier into the audio band to minimise the noise, result (soft/opaque/dark treble and upper mids and hf phase shifts)

2: The filter to roll off later with no treble roll off and minimized hf phase shift, but let 10 x the switching noise through (hard in your face treble and upper mids).

Or we bite the bullet and use Class D just for bass, and wait for technology to advance to get much high switching frequencies for class D so we can then filter them out much higher and more aggressively with being near the audio band.
It will happen one day and that's when I will get one as well, but today it is just not ready yet, it's still developing, when it does our heavy massive linear amps will become boat good anchors.

Cheers George

George, are you saying that you audition graphs, and faithfully follow those pundits who seem to suffer from Princess And The Class-D Pea syndrome?

Your implicit trust in the press is admirable... It spares you from the unavoidable surprises of audible reality

G.

No, you asked me what I listened to, cause of my pessimism.

And I said "many" and they all have the same trait/s.
And then I gave reasons "cause" to why I hear this.
One day they will come of age, then I will own one.
You choose not believe? I can't help that.

Cheers George

We ALL just need to believe one guy more than our ears.

Designers and fans of digital amps - Theta, Veritas, Bel Canto, Rowland, etc - who cares?
They all don't hear so well, no?

3 words come to mind - dogma, dogma, dogma.

Right on Jon, my old hearing is clearly impaired *grins!*

Actually, I examine amps one brand at a time, and one model at a time.

Currently, my favorite uber amps sound comes from Acoustic Research, Brmester, Solution, and yes... Rowland. Any of these brands have some machines that make enchanting music to my ears.

Class D has the same potential for good and bad sound as any other base topology... It all depends on componentry, goals, design, and implementation. All other things being equal, The common advantage of Class D over other topologies remains energy efficiency, hence minimum cost of operation.

Is class D inherently great? Heck no! I have heard certain current class D amps sounding positively acrid... Best used in attics.... They chase Roaches and other critters away for pennies a day. But so do some much vaunted class A/B devices, and more than a handful of tube amps... At a higher operating cost, that is *grins!*

Bottom line... Generalizations are a slippery business.

G.