Quoted from Rarehero:
One of the many reasons B/W collectors hated Stern was the sound, as it was indeed dated. DCS & WPC’95 blew it away.
In the 90's, I get it... But today, I find the audible compression artifacts and noise-static irritating. Perhaps it's MY games or perhaps nostalgia is a factor.
I've had TZ for 20yrs and the audio is 'fine' for me. But I recently picked up a nice Addam's Family and immediately upgraded the speakers, added pinsound, etc.
BTW, you can switch mixes (new, original, etc.). I prefer the new mixes, they change the vibe of the game, but it's interesting to switch back to the original sounds.