The Future of Audio Amplification

Zero-feedback Class D would seem to be a unique twist.

hello brotw 
Sorry for the late response, this thread has come to large and techincal. I find it hard to follow.
Well, my Nord NC500 One UP is just burning, but even out of the cage it sounded better than the LM508, to my ears and in my system.
I also have to say that the Nord only has about 30 hs of use and it has a long way to go before reaching its best. Nevertheless, during this period I know it will sound sometimes better and sometimes worst. For instance, I found it yestarday a "little bit" thin and harsh, more than at the beginning. I'm sure that it will get warmer and more delicate with time, as it happened with other owners.
I also have to say that I really like my LM508 and I would like to compare both amps again, once the Nord has settled down, in a few weeks. But I also have to mention that I was expecting subtle differences, if any, but I found out noticeable ones, mostly in texture, noise and 3D image.
FInally, I don't think Digital Room Correction has something to do with the amp and the speakers. For me it makes the sound much transparent and plus I have the option to set it to my taste, rising some frequencies and lowering others.

Zero-feedback Class D would seem to be a unique twist.

Bit late to the party Merrill already did it using the GaN transistors, I believe the SE-R1 does also.

Merrill Quote:
 Merrill Audio claims that this is by far their most ambitious design mostly because they are using open loop, zero feedback, and zero deadtime with GaN  gallium nitride transistors, which are better than most transistors used in other solid-state amplifiers because that have close to zero capacitance, which allows fast switching.
Plus, the gallium nitride transistors can operate in the GHz range. Gallium nitride transistors offer a fast, clean, low distortion power capability", and so Merrill Audio claims that are "natural and smooth in their musical capability".  And after doing this, since the distortion was eliminated, there was no reason to use any feedback at all. He went on to tell me that he is very proud of not having to use feedback.  Eliminating feedback has two distinct advantages. The speed capability is increased significantly and a remarkable gain in the clarity of musical information is achieved. Since there is no signal loop-back, all the feedback loop distortions as well as the attendant time delays are eliminated.  

Cheers George

There are two reasons I will be keeping my Class D amps for a long time:


1) they work and sound great

2) the longer I wait the better (and more affordable) this still evolving technology will continue to get in years to come for many many reasons.

Same reasons I tend to hold on to most good quality digital gear (and cars) I buy for as long as I can as well.

BTW I believe it was Merrill Class D amps I heard driving German Physiks speakers at CAF 2017 and loved what I heard, not unlike what I hear with my Class D amps and OHMs at home.

piaga, for some reason I do not see your post which starts out ...

 01-03-2019 2:42pm EST hello brotw Sorry for the late response, this thread has come to large and techincal. I find it hard to follow.Well, my Nord NC500 One UP is just burning, but even out of the cage it sounded better... View full response →