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High end Class D amps?

Just an observation and a question. Are there 'high end' Class D amps out there that are just as good as Class A, A/B amps? I realize that's a sensitive question to some and I mean no disrespect---but whenever I see others' hifi systems on social media, all of the amps are A or A/B. There's always Pass, McIntosh, Moon, Luxman, Accuphase, etc. Where are the Class Ds? For folks out there that want more power for less efficient speakers and can't afford the uber expensive Class As, A/Bs, what is there to choose from that's close to those brands? Thanks
bluorion
georgehifi's avatar
georgehifi
10,312 posts
 

audio2design Why would a Class-D amp care about phase angle?

Any amps do, but react differently to it, - phase angle when combined with the speakers impedance is called EPDR (equivalent peak dissipation resistance) and is what the amp really sees.

And it’s that combination that’s presented to amps, by many speakers, that can freak them out.
Dismiss amp builder that says it a furphy,https://www.dictionary.com/browse/furphy

Here is just the Wilson Alexia, it rated as a 4ohm speaker, but!! combine that with the -phase angle it’s got and the amp sees 0.9ohm in the low bass!!!!

https://ibb.co/Zzsqsr0

https://www.stereophile.com/images/718WAlex2fig1.jpg

Cheers George
audio2design
1,351 posts
 
I will repeat my question, why would a class-D amplifier care about phase angle. The data you have presented only applies to thermal loading (hence dissipation resistance) in the linear region of semiconductor devices (It would apply to tubes as well, but don't think it would be much of an issue). Class-D semiconductor devices operate in saturation and would not be impacted by this.
atmasphere's avatar
atmasphere
11,793 posts
 
Class-D semiconductor devices operate in saturation and would not be impacted by this.
That, and the fact that the amp has an output impedance of a handful of milliohms. Phase angle isn't going to affect it.
audioman58's avatar
audioman58
4,133 posts
 
Jeff Roland,Mark Levenson 
Merrill Audio , Gato Audio
georgehifi's avatar
georgehifi
10,312 posts
 
I will repeat my question, why would a class-D amplifier care about phase angle.
I’ll repeat my answer in another way, negative phase angle combined with low impedance can as in the Alexia, gives a EPDR of load as seen by the amp of 0.9ohm load!!!!
Now you go find a Class-D that will keep pushing even more current into that kind of loading like a good bi-polar amp can.

If you can hear it at a shop with speakers like the Alexia you'll be stunned at what just a good 100w bi-polar amp like Gryphon v any Class-D of any wattage, the Gryphon will be superior at those EPDR frequencies in the bass.
 
Cheers George
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