Just heard a song by someone. Great little tune, nice wide stereo field. Sounds really good. Until you hear it in mono. Then all the guitars disappear. Gone. Who cares? Who listens in mono? Well, because as recording/mixing engineers, our job is to make sure that our products sound as great as possible on all possible sound systems.
I’m not sure who listens in mono anymore. Well, I know one person, and that’s me, but it’s totally by accident. See, the record player I have came with a mono cartridge, and I don’t really want to change it to a stereo one because it’s a Fairchild cartridge. Yup, that very Fairchild who made the famous 660 and 670 limiters.
So, when mixing, why on earth would anyone bother with worrying about mixing for mono, when there’s only one guy that we know of who listens to things in mono?
Well, imagine this: you’ve mixed a record and it sounds really nice…you’re sitting in front of the studio monitors and everything is well balanced, the stereo field is nice and wide and everything sounds really big, almost like the sound is coming from somewhere outside the speakers perhaps. The record goes out, and gets mastered. Then one night, you’re out in a club seeing your favorite local favorite band play, and a familiar song comes on while the band is setting up and the soundguy is resetting the stage. “This song sounds familiar! Hey, I recorded this!”. But much to your horror, the mix sounds one dimensional and, “oh shit, I totally under-mixed the guitars! Wait, this sound system’s fucked up!”
Well, could be that the sound system is fucked up, but chances are semi decent that the PA is actually in mono, so your nice wide doubled guitars that you so proudly mixed to sound big and wide actually canceled each other out when the song was summed to mono. And not only that, but the drums sound kinda fucked up too…where’s that nice room sound, or cymbals (or whatever).
This is only one example of a place where your nice wide stereo mix can get screwed up on a playback.
I’ve heard stereos totally screw up mixes because they have a built in “surround sound emulator” that makes things sound really wide. The opposite of the live sound thing happens in this situation….all of a sudden, “Whoa! Those guitars are too loud! And the drums sound WAY too roomy! WTF?!”
There are also folks out there in the world who have no idea that they need to hook their speakers up so that they are in phase. As in their home stereo speakers. You need to deal with them too.
So, what a drag, hug? We have stereo to play with, but all of these things, and many more, can fuck up the listening experience. Now granted, most of the folks in the world won’t have any idea that the way your mix sounds through any of those sound systems isn’t the way it’s supposed to sound, but to me at least, it’s a problem.
Why does this happen, this stereo to mono weirdness? Well, it all has to do with phase cancellation. I can’t possibly explain how it all works because I’m not smart enough, but basically, for example, when you mix those nice wide doubled guitars, there’s some phase cancellation going on that you’re not going to hear when the guitars are coming from two different sound sources. But when they’re coming from one (mono), they cancel out. Not 100%, but enough to drop the volume noticeably. Same goes for drum overheads (or even your close mics on the drumkit) or room mics, stereo piano etc etc etc.
So how do we get around this?
It’s pretty simple. Check your goddamned mixes in mono.
Except it isn’t just that simple. It isn’t that simple because we want things to sound really great in stereo because that’s what most people are going to be listening to. Stereo.
But I fuss over this stuff because it’s my job. So what do I do to combat the mono/stereo problem?
I’ll tell ya.
For one, I almost never pan anything hard left and right. At least nothing too important. For example, if it’s a “regular” rock band, with two guitars, bass, drums and vocals, bass and vocals go up the middle (as everyone else does) but I will only pan the two guitars at about 50% or less. Some of you will be saying, “that’s stupid”, and I won’t argue with you because I don’t care. But the thing is, the ear will still hear it as being in stereo with headphones or sitting in front of a pair of speakers, but I will be able to make the guitars be pretty equally loud in the stereo mix as they would be if they were summed to mono. And they tend to be louder and bigger than they would be if they’re panned 100% left and right.
Same thing goes for drum overheads. They stay pretty narrow in the mix. Again, less than 50% panning. But you put headphones on and they still sound wide.
I should note here, that whenever I’m doing basics for drums, I am always listening to the sounds in mono for the first few minutes. Once I get levels and balance, THEN I start panning things. Makes it easier in the long run if I do this.
I will of course pan some things very wide. I depends on the song, but things that tend to go wide are usually vocal effects, like an Eventide type of effect, or ping pong delays (not the main reverb tho…that stays at less than 100%, and the more verb I use, the less panning usually happens). Also things like percussion, or ooohs and aaaahs might go wide. But I am very careful to only put things wide that won’t be missed if they disappear in the mono summing. And when I’m mixing, I am constantly checking in mono (although less and less it seems these days, as I’m getting used to what things are going to disappear in mono when I hear them in stereo).
I think a lot of young engineers (and some older) get tempted by the big wide stereo thing. Stereo acoustic guitar is usually just asking for trouble. A spaced pair as drum overheards is also asking for trouble (X-Y is the way to go for mono compatibility. Google it.) Piano is really tough because to get a nice close modern sound with a grand piano, you kinda need to use a couple of mics. But if you have a nice wide stereo spread with the piano then dump it down to mono, all of the air goes away from the sound. I deal with this, again, by getting the sound in mono, then going to stereo once it sounds good in mono.
Sometimes I think about future generations. Who knows what kind of sound systems they’ll be listening to in 300 years? Could be some crazy assed 92 channel speaker setup that makes everything bounce around the room in some kind of holographic sound or something. Dunno. But I know that anything that will be I mixed to be mono compatible will probably sound really freaking good in those 92 speakers.
So, in trying to summarize here, I feel like it’s important to check to see how things will translate to mono not just to make sure things are sounding good in mono, but also to insure that things will translate better over all sound systems, from earbuds to gigantic stadium sized sound systems. I’ve heard my mixes on systems on both extremes (I must say it’s a treat to hear stuff coming thru a giant sound system), and they have all worked for me since I started trying to make things mono compatible.