Quoted from PinballHelp:

What club are you going to? Again, you guys need to raise your standards. I don't even know if anyone sells a mono sound board any more. Most clubs I know of are at least 2.1 sound. And I've been a FOH & studio engineer for 20+ years and we run anywhere from a 4-24 channel main bus depending upon the venue.

24" is plenty to achieve good separation. When someone finally pays attention to what you can do with audio, you guys will see the potential that you're missing. The problem is, audio has been of little interest to the pinball industry historically. It's disappointing that JJP only made WOZ 2.1. They could have made a 5.1 or 7.1 system and had jacks so that the games could be plugged into surround systems... once someone does something like this, everybody's going to freak out and wonder why it wasn't done sooner. But the second half of the equation is the sound mix design. Even if you're running in stereo, if the mix isn't interesting, it won't matter. But when you've got a good mix + a good system, the result is amazing. The first time I heard "One" and the lead guitar sneaked out from one of the channels with the rhythm guitar on the other, I got chills... It's a shame Metallica is in Mono. Stern could also put a headphone jack with stereo output if they wanted to do justice to the original music.

Quoted from Purpledrilmonkey:

Is it a fact stern is resampling to 24khz? Seems hard to believe as I'm not noticing frequencies above 12khz being filtered but maybe I haven't paid enough attention... I mean the cd audio tracks would be at 44.1khz so why they would downsample them i have no clue. But Like I said... I'm busy playing pinball haha I might run the machine thru a parametric eq just to take a look at the spectrum for kicks... Lord knows the speakers aren't good enough to fully present the audio properly in the first place.

Quoted from Wamprat:

Not the best stern but it is better than acdc........... but that wouldn't be hard.

Quoted from jar155:

I see. I don't think I could dislike Avengers any more than I do. I find it to be an absolute failure of pinball design. Guess it's just a case of wildly different opinions here.