Digital Amps? Marketing Hype?

My basic electronics are rusty, but as i recall amplifiers were classed by the amount on time they conducted during a single cycle of the input waveform (a sinusoid for simplicity's sake). The term digital implies discrete states,on/off, in this case the output device (tube/transistor). It may only be semantics we are arguing, but if so, then only class A amps can be truly be called analog since all other classes are on/off for portions of the cycle. In this sense, they are digital; however, by convention, they have never been described as 'digital'.
It seemed to me to describe an amplifier as digital was to suggest a completely new design that did not encompass the class designations as generally accepted.
So you are right Kr4, I do need to do some research; however, it seems to me that class D amps are not digital but rather 'described' as such. I am not familiar with the digital ammps you mentioned, but it seems they behave as DAC's. That is, they pesent to the speaker load a signal which approximates an analog signal. It is the physical limitations of the drivers (load) which actaully produce an analog signal. Your thoughts?

Use your own ears but I was ready to lay down some long green on an Ayre V5x amplifier until I heard the Spectron Musician II digital amp.

I have been through more amplifiers than I care to count in the last 10 years. Did I say twenty-eight! I have had Spectral, VTL, VAC using 300B's, MacIntosh, Sonic Frontiers, Audio Research, Graaf, Crown, single-ended 2A3's, Pass, Edge, Polyfusion, Ayre V3, ... you get the idea.

The Spectron just flat-out floored me. I have Maggie 3.6R's that demand current. This amp cuts muster. All who have been over to the house have been mightily impressed by what they hear. The amp is able to belt out 650 wpc with 40 amps peak current and the Maggies just cruise. What the Spectron does that no other digital amp has done, so far, is provide a feedback loop from the speaker. The amp takes the speaker cable out of the equation so the signal that arrives at the speaker is the same that left the amp. They accomplish this by using sense cables. The designer was an engineer in the defense industry and one of the original founders of Infinity, the famous speaker company.

With his design I hear so much deeper into the soundstage with imaging that is rock steady. I don't hear solid state or tube sound. I hear music. Dynamics are broad and transients are crisp but not biting. Bass is full and fast. No edge, no glare, no hype.

As far as cost, yeah, it should be coming down. When Bel Canto can charge nearly $3000 for their digital amp using a module that costs on the order of pocket change, that is just taking advantage of their position being one of the first to market.

I use a Sony SCD-1 SACD player with Richard Kern modifications feeding either a Reference Line passive attenuator or an over-achieving tube preamp, the Eastern Electric MiniMax. Interconnects are the Harmonic Technology Pro-Silway II's. I sold my Harmonic Technology speaker cables because the sense cables sounded so much better.

I agree with jwmazur. My speakers are way hard to drive. (DQ-10's modified for biamping).
In fact, I bought 2 PS Audio HCA-2's since I've had problems in the past trying to get life out of the bass.
I found that 1 drove them beautifully and now have the other for sale.

Jlamb, you might want to check out the Tact web site for some interesting clarification.

"So you are right Kr4, I do need to do some research;"

Yes. There's a lot of info out there. Try the Tact and Tripath websites for a start.

"however, it seems to me that class D amps are not digital but rather 'described' as such."

Depends on your definitions. I tend to agree with you but I am not bothered by this minor shading of word use.

"I am not familiar with the digital ammps you mentioned, but it seems they behave as DAC's."

Some do.

"That is, they pesent to the speaker load a signal which approximates an analog signal. It is the physical limitations of the drivers (load) which actaully produce
an analog signal. Your thoughts?"

All have a reconstruction/HF filter at their outputs, so that they output a smoothed analog signal. Relying on the speaker/crossover to do this would be an uncertain application.