Si que tienen sonido (no se el de NeoGeoPC) pero el resto sí (te lo dice alguien que sabe.
Así por ejemplo tenemos para emular GBColor el GamePhone:
"This is a GameBoy/GBC emulator by Infinitouch Global Limited. It does not have good documentation at all, but it has redefinable keys, save game support, and a sound on/off switch."
O el GoBoy Plus:
"It's in earlier development, but has sound and zip support."
Para recreativas el EMAME:
"Has fairly good compatibility, but is a bit slow. Sounds works in some games, but not in others."
El YewNES te emula la Nintendo NES (Famicom):
"It's compatible with over 1000 games, has a screenshot function, scanlines, speed levels and more."
Y así bastantes más. La cosa está interesante...