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Class D amps seem poised to take over. Then what?

I am certainly biased by my lifetime final amp being a Class D. But I know that after 30+ years of development, Class D seems to be on a high plain. I know there are now many, many companies focusing on Class D and, maybe, a good handful already as good as it gets. My Class D amp is as smooth and beautifully musical as a great tube amp and as punchy and detailed as a great SS amp. I am satisfied and done with my search. A class D amp has effectively taken me off the amp merry-go-round. It’s about time after 50 years. And, for me, this Class D is a milestone. Will all other classes of amps fade away?
mglik
georgehifi's avatar
georgehifi
10,312 posts
 
You keep mentioning Wilson’s as being hard to drive, where does this come from?

For someone who "says" they’ve owned Wilsons, you are not very au fait or even interested in how they measure or behave, in particular the loading they present for amps to see. And they have many models that are in that same low EPDR loading bracket.
From HiFi News Lab Report
Impedance phase is quite well controlled but still the EPDR falls to a low of 1.2ohm/67Hz, with further minima at 129Hz (1.8ohm) and 410Hz (1.9ohm). So the Alexia 2 presents a challenging load to the amplifier, albeit not so much as its predecessor Mk1 (min EPDR 0.9ohm!!!!).

invalid
1,226 posts
 
These companies that claim double wattage when impedence is halved don't give the actual 8ohm measurement, which is usually a lot higher wattage than their spec sheet has listed.
georgehifi's avatar
georgehifi
10,312 posts
 
These companies that claim double wattage when impedence is halved don’t give the actual 8ohm measurement

Usually if they don’t, they are hiding something. Stereophile does for Class-D if you read the Lab Tests on them and that’s usually is in the negative.
But even Stereophile doesn’t usually do 2ohm testing on Class-D’s as they are usually pitiful, when compared to the good linear solid BJT state amps for putting out big (doubling watts) current.

Cheers George
invalid
1,226 posts
 
Even the big high bias amps built with BJT's can't do it. When stereophile measures them their 8ohm full power measurements are a lot higher than the spec.
invalid
1,226 posts
 
I don't think there is an amp made that can direct drive the apogee full range, the midrange when direct driven is .14 ohms
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