Dear Andy,
When I mix in my home studio, the sound field and ambience sounds weird when I listen in mono. What's the problem?
Radio-Head
Dear Radio-Head,
Important question - does anyone still listen in mono? The answer is...they should. Here's why. Mono compatibility is often a revealing indicator of overall good balance and a mix that will ultimately sound good on lots of systems.
First, as you build your mix, try slightly closing the pan pots on some of your stereo images. Stereo piano and other stereo elements often will hold their sonic personality better by not being 100% panned.
For a real radical approach, try taking some of your stereo images - especially synth patches - and "mono-ize" them. Then pan those sounds like organs, stereo guitars or clavinets to one side or the other of the stereo field. This can open up huge amount of sonic space in the mix and leave more room for vocals, pumping bass sounds and driving drums that, more or less, have to be in the center.
Finally, try building your mix with the mono button on. After all the parts are in good balance, switch to stereo. You'll be amazed how your mixes will hold up better on multiple systems.
Good Luck!