Class D is just Dandy!


I thought it was time we had a pro- Class D thread. There's plenty of threads about comparisons, or detractors of Class D.

That's fine, you don't have to like Class D amps, and if you don't please go participate on one of those threads.

For those of us who are very happy and excited about having musical, capable amps that we can afford to keep on 24/7 and don't require large spaces to put them in, this thread is for you.

Please share your experiences with class D amps!
erik_squires

Thank you Eric, nice to see an Audiogon watering hole for fans of good class D amplification. Over the years, I have had a variety of very fine amps.... Among class D designs I enjoyed for several years the Rowland 312 stereo based on ICEpower ASP1000, and the Bel Canto REF1000 MK.2 -- also based on ASP1000. I agree with Ghosthouse that Merrill makes wonderful amps based on NCore NC1200 and NC500... Worth not only listening, but also owning. Read my super-favorable review of Merrill's Veritas monos at on Positive Feedback No.68:


http://positive-feedback.com/Issue68/merrill_audio.htm


 My reference amplifier is the Rowland M925 mono, also based on NCore NC1200 modules, amongst its many component parts... It is an absolutely enchanting amp, which I have discussed elsewhere on this forum:


https://forum.audiogon.com/discussions/experiencing-rowland-m925-4-chassis-reference-amps      


Yep, 4 years have elapsed since M925 has arrived at my doorsteps, and I am still in love with it.


Here is where you can find information on M925 design and architecture:


http://jeffrowlandgroup.com/kb/categories.php?categoryid=212


Saluti, Guido





I have had Nuforce Reference 9 V2, the V3Se and Now Nuforce/Nuprime Reference 20 monos. They have bested in my opinion all Class A and A/B designs that I have heard with high end Pass Labs coming closest to reflecting the beauty of music. Also Nuforce best of the 5 Class D amps that I have heard which were all great in the bass but not as liquid and natural in mids and highs. Plus I do love the size, weight (which allows me to easily take them to other's homes and compare to their amps or ship for mods) and continuous on because of low power use. Have found class D to be sensitive to power cords, electronic and mechanical isolation, long break in and warm up. I agree with many that they are especially nice paired with a tubed preamp, in my case Ayon.
Guys,

You know I was just thinking about something. If the current crop of digital amps had appeared in the 1980's I think they would have pretty much ended the solid state / linear amplifier market.

The SS amps at the time were, by and large, full of compromises, and consumers were hungry for all things digital.

This did not happen however, the digital amps of the 1990's weren't nearly as good as they are now, and solid state amplifiers also continued to advance to where they are today.

Still fun to think about. :)

Best,


E
The 60’s 70’s 80’s were the change over from germanium transistors to early silicon transistors, and the amps around at that time were ? to say the least. A good tube was better to own still. But the silicon transistor has advanced, so to circuit design.

I’m still waiting for the transistor that will take Class-D to where it will eventually get to in the rankings, Technics are using a super transistor (not available for everyone) for their SE-R1 Class-D poweramp (special order only), but it’s a $20k-$30k amp, it shows what’s ahead in the future for Class-D

http://www.technics.com/us/products/r1/se-r1.html

Stereophile listens. Technics SE-R1 Stereo Power Amplifier
"This amplifier delivered some of the best reproduced sound at CES 2017
The broad and deep soundstage, imaging, upper midrange detail, and bass extension were thrilling during the system’s rendition of "Lord, make me an instrument of thy peace" and "Pie Jesu."

Digital Trends Listen: Technics SE-R1 Stereo Power Amplifier
" Not only are we hearing things we’d never heard before, we’re hearing it in a way we’ve never heard it before. A music system that sounds like a live performance is a tough goal to attain, but Technics’ flagship nails it.

This is all due to the higher switching frequency (double of what's around now)  of these special transistors.

Cheers George
Interesting, @georgehifi re garding transistor manufacturing.

In 1976 Dr. Leach introduced his paper, Build a low TIM amplifier which transformed, if not codified, what would be linear amplifier design for the next 3 decades.

Also 80's were flirting with MOSFETs that promised to behave more like tubes. High input impedance, more linearity, blah blah blah. and some worked out, some worked out some of the time. :) I think James Bonjiorno (spelling?) and Sumo in general were among the early names that were associated with this. But we digress.

Well, there is always some technology around the corner, some new way of winding a transformer that promises never-before heard of improvements. 99% of the time, these changes don't pass the test of time, and are forgotten by their own inventors, or fail to make enough of an impression to be adopted by others. There are also a number of amplifiers who end up being door stops once the manufacturer of the super-special magic transistor stops making them.  << sigh >>

Remember Halcro with their super low distortion, universal accolades? It went under, came back... and now who knows.

I guess my point is, we can always look forward to new things, but we can't let that stop us from enjoying what we can get now. :)

Best,

E