Originally Posted by Nicholas Bedworth
Are there any new designs out there that are closed loop and have similar stellar performance?
Not that I'm aware of -- Zetex (bought by Diodes Inc.) had unique circuit architecture IP giving some fundamental performance advantages, and I don't know of anything comparable from anyone else.
Unfortunately Zetex only supported the OEM market, and seem to have had much less success in that than was predicted -- my guess is that the big-volume Far East OEM audio manufacturers (home cinema etc) care more about the fact there are cheaper class-D solutions available than the fact that Zetex's is better.
Which is a pity, having designed the crucial low-jitter circuit circuits for Zetex we got to both listen to and measure the DDFA and were blown away...