Anyone using a Class D amp w/ribbon tweeters?


I'm looking for some feedback about using a Class D amp 
with speakers that use ribbon tweeters. 

Anyone have any experience? How do they sound?

At least 3-4 years ago I was still believing that ribbon tweeters 
were not a good mix with Class D b/c of the sibilance it produced from the tweeters.

But now we have gone from ICE modules to NCore, Pascal, etc 
and other proprietary designs (Dig Amp Co) that may not be so bright, digital etch, etc

Anyone know about using more modern Class D amps with 
ribbon tweeters while having better control of the high frequencies?
Thanks
Gary
128x1281graber2
@mapman 
interesting what you say about the Bel Canto C5i (same for the C7?), 
that has been on my list of "all in one" units to pick up 
and play with as an extra system in another room. 
I was worried that it might have some upper end grain.
@aolmrd1241 
Yeesh, this Merrill Class D monos are ridiculous! (aka awesome),
as described on the Merrill site, 

"Start with a 66 pound of Aircraft grade 6061 solid aluminum block. Delicately machine the chassis from this solid block isolation chambers to limit any sonic interference and minimize vibrations. Keep the walls 1 inches thick, to limit and absorb vibration. The result is a ..."
and I hear no top end sibilance
What I’ve heard is either two things in the upper/mid highs from Class-D, either sibilance as mapman mentions or an opaque whiteness.

This to me comes from "high power the low order switching noise output filters" either "set too high" which lets through too much of the switching noise (sibilant) and some audio band phase shifts, or "set too low" which hacks out most of the switching noise but also hacks into the audio frequencies upper mids ,highs (opaqueness) and creates not only attenuation but even larger phase shifts than the "too high" filter does.

The only way to fix this to me is to raise the switching frequencies much higher so the "high power low order output filter" can do it’s job properly without any effects down into the audio band. As Technics have started to do with the flagship SE-R1 with more twice the switching frequency of today, but at $30k aud and limited supply.

BTW you can see this switching frequency noise on Class-D amps in Stereophile bench tests that sits on the 10khz square waves, like a buzz saw across the top of the square wave. https://www.stereo.net.au/forums/uploads/monthly_2016_12/583f6e91157f6_Class-Dsquarewaveringing..jpg...

But last year or so Stereophile have introduced a special filter (Audio Precision’s AUX-0025 passive low-pass filter) that goes between the the Class-D amp and the test measuring equipment that gets rid of the buzz saw, just for Class-D tests purposes, they always say they use it somewhere slightly hidden in the bench test reports. ( Belcanto with AUX-0025 filter applied https://cdn.head-fi.org/a/1862061_thumb.jpg) Still to me a disgusting looking 10khz square wave, but better than the buzz saw with the special filter.
This is what a proper Linear Class-A/B amp square wave looks like. https://cdn.head-fi.org/a/1862052.jpg


Cheers George
Igraber2 the c5i is had to fault. Simply wonderful. About the size of a shoebox. 60 watts perfect for my second system. If it just had more watts I would put it in my main system and just forget all the separate components. My main system is ARC sp 16 pre to Bel Canto ref1000m Class D amps to large OHM Walsh speakers with 12" driver that love power and current.

If the c5i did not work out I was going to go tube amp.   Never happened.   I've had the c5i for a few years now.