I have switched from ne5532 to lm4562 in Aiyima a04 tpa3251. The sound is a bit better with lm4562. Its a fantastic amplifier.
Right now there is people comparing Aiyima a04 tpa 3251 with a Rotel ra1592 and a Hypex nc400 amplifier. Its the ”new”version of Aiyima a04 with the green card .
The Aiyima a04 with opa2604 is sounding better than Rotel ra1592 , better bass and more clear sound, and theres no difference against Hypex nc400.
Read more here:
https://www.faktiskt.io/phpBB3/viewtopic.php?f=9&t=70688&start=360
green board? does it have a revision?
i recently ordered a A04, i have the black board, 'TILEAR HD325X Rev:2.1' as the markings