Here are some of the best things I’ve learnt since I started mixing.
Tip 1: Rest Your Ears
If you’re mixing for a long amount of time you may be thinking your mix is going well when in reality it’s not. This can be a problem for people who refuse to stop until they are 100% happy with their results. I do this sometimes myself.
But your ears will eventually begin to get tired and you start hearing things that aren't really there. That awesome guitar you've spent hours mixing will end up sound like crap the next morning when you listen back to it.
Your ears can neglect certain frequencies when your ears get tired and you pay too much attention to specific frequency ranges you lose sight of the bigger picture.
Tip 2: Mix At Lower Levels
This is very important. I think most of us know that loud music always sounds better because it allows the frequencies to spread out more.
Our ears are most sensitive to mid frequencies, but by playing music louder it evens everything out making high and low frequencies stand out more.
This is why loud music is more appealing. Why do you think venues play music so loud? It’s not always so everyone can hear. They sometimes keep the master volume down 5 dB until the last song then put it up, so the last song sounds better making the audience leave with a more positive opinion on the show.
So which is the best level to mix? You should usually check your mix in different levels to make sure it sounds fairly level-proof. A multi-band compressor on the master track can also help compensate for this. Usually mix at about conversation level - if you mix sounds well at a quiet level it should sound amazing at a high level.
Tip 3: Mono Listening
Checking a mix in mono is very important to make sure everything is sounding balanced. You may notice holes in a mono mix that you might not hear in stereo.
This may seem pointless as most things are now stereo but a lot of places still use mono. AM radio stations broadcast in mono. Cheap TV's with 1 speaker and so on.
If you hear very little difference between switching from stereo and mono you might want to consider more panning.