Mytek slams Hypex in Stereophile Amp Review

Mytek’s chief designer, Michal Jurewicz, told me. "Hypex [class-D modules] cannot drive it, the amps collapse

That’s the pot calling the kettle black

Though Mytek ultimately chose an amplifier module from the Danish company Pascal

Pascal use tweaked $100 Sanway subwoofer modules and also supply them to Rowland for their $10k Continuum 2 amps and Red Dragon also use, but only charge $1k for.

Rowland Contiuum 2 $10k
https://ibb.co/RcVqXGt

Sanway $100 subwoofer plate amp module.
https://ibb.co/5YvR1dG
https://ibb.co/vHhF64r
https://ibb.co/yQxbq3v

Red Dragon $1k mono amps
https://ibb.co/RTGJg0X

Six Moons
"Jeff Rowland have been one of Pascal’s earliest customers among high-end manufacturers to release a few ‘entry-level’ products based on that module like the bridgeable 525 stereo power amp and the integrated Continuum S2. Red Dragon’s S500 beats with the same heart in a less high-end chassis"

Moral to this? can’t trust any boutique $$$$ Class-D manufacturers their all in it for the massive mark up $$$$$, maybe Red Dragon as they haven’t jacked up the price too much, and are continually sold out because of it, you get a lot of bang for your buck with them

If you really want high end Class-D and have to pay for it, go with the more advanced technology that addresses the problems to a much greater extent of all class-D’s, and that’s the Technics SE-R1

Cheers George

Not exactly how this works, but yes, large phase shifts mean high currents near zero volts. Hard for most amps. Would be nice if we had impedance graphs for the Duntechs.

There is a formula for it, on diyAudio somewhere, but as usual it was in my head while I needed it, but soon sieved out of there in a hurry, like rats on a sinking ship.

As for impedance graphs with -phase layovers, Stereophile is the only one to do this, but they never use the EDPR formula to give the real load the amp sees.

Only one I’ve seen do this is Miller Audio Reasearch Test Labs, when they did 3rd party Lab Report testing for HiFi News and Record Review, like they did on the Wilson Alexia, which managed an EPDR of just 0.9ohm!!!! in the bass.
https://www.absolutesounds.com/pdf/main/press/WA%20Alexia%20HFN%200313-4web.pdf

Cheers George

The Duntech Sovereigns are specified as being 3 to 4.5 ohms. That is well within what should be the Hypex’s comfort zone.

Not if there's a -50'-60' degree negative phase shift also at 3ohms, then the amp could be looking at nearer 1ohm.

Mytek ultimately chose an amplifier module from the Danish company Pascal

And this could indicate Pascal get them from China and mod them. As are Red Dragon and Rowand Research

http://www.pascal-audio.com/amplifier-modules.html

http://www.theaudiobeat.com/equipment/pics/jeff_rowland_continuum_2_large_inside.jpg

https://www.reddragonaudio.com/products/s500?variant=969867425

https://www.stereo.net.au/forums/uploads/monthly_2017_05/Capture.JPG.eecf146fa0c42ac376beb2799afd581...

Cheers George

addyson815
If your going to copy and paste something from an article, you shouldn’t do just part of it.
"Duntechs, with their multiple drivers and complicated crossovers, are a very difficult load"
" Hypex [class-D modules] cannot drive it, the amps collapse"

But that’s always been the case with Class-D, get a speaker that has an EPDR load (combined impedance and -phase angle) of <2ohms and they **** themselves. And this kind of this load is in more speakers than what your aware of it’s hardly ever measured or printed.

Cheers George