Often it is suggested to collapse low frequencies to mono by default, often even on the master bus.
Personally I think this is a bad idea as general 'rule of thumb' when mixing; I'd never collapse all the the low end to mono if it's not necessary, and I believe usually it is not.
So why is this often encouraged?
1) There is very little stereo information in the bottom end
2) Audio systems with a sub will collapse the bottom end to mono anyway
3) There can be phase cancellation issues there that you can actually see on your L/R correlation meter
4) The bottom end sounds more punchy when it's mono
5) You can do more extreme panning without it sounding weird on earphones
That's the argumentation I could find and this is what I think about these points:
1) While this is true, it's not 100% true. In my experience you CAN lose something in the stereo image if you just collapse everything to mono in the low end. For example if there's low-end ambiance going on, it can sound awesome on headphones.
2) This is also true, but most audio systems don't have a sub. Perhaps it's more a matter of making your mix work with a mono sub rather than automatically adding more filtering and processing just to be safe. You can check by just listening to your mix in full mono; why do we need to do more?
3) If you're trying to fix that with collapsing your low-end to mono, you actually aren't. Sure, the L/R correlation meter won't show the issue anymore but that's just because the damage is already done before hitting the L/R correlation meter (it simply won't detect the real issue anymore); you probably need to do something else to fix the actual problem.
4) I think the bottom end sounds more punchy when it works in mono, but not necessarily *because* it is mono. Again, you can just check by just checking your mix in full mono.
5) Sure, if you pan a bassguitar left and a guitar right, it is unlistenable on headphones. In such cases, collapsing the low-end to mono will definitely work. But how many times do you actually want to do that? This is a corner case.
Sure, kick and bass in the center and those should sound good everywhere, I get that. But there's a bit more going on in the low-end. Personally when I try to enforce a mono bottom-end, it seems like a concession not worth making when I'm listening with earphones or my monitors. Don't fix what isn't broken?
This (rambling) post is not meant to claim that I know better: I'm just quite confused about the subject and why the consensus seems to be that a mono bottom-end is always better.
Cheers,
Erik
Tony Loignon.
Erik Duijs
face (chris) Janton
Mike Morrison
Mike Morrison.
Tony Loignon