1. Waiting until the end of the mix to add compression to the mix bus.
This is the easiest way to unravel a great mix. If you want to compress the entire mix (which is totally fine to do), make sure you add the compressor to your mix bus EARLY in the process.
Then make all your mix decisions while listening to the mix THROUGH that compressor.
Well, I don’t think so.
Yes, mixing into a compressor is common technique, but that doesn’t mean it’s the only way to do it. There’s nothing wrong with getting a finely-balanced mix without any mix bus processing, and then applying gentle compression over the whole lot in the final stages of the mix. Yes, it’s possible to overdo anything and end up with a mess, but it’s also possible to get great mixes by applying compression at the very end.
Of course, it’s easy to do badly and, like most aspects of mixing, it’s easier to do badly than it is to do well. But is it “the easiest way to unravel a great mix”? I don’t even know what that means. If you have a great mix, isn’t it already finished? If you wanted to ‘unravel’ it, you could start by pulling all the faders up to unity and deactivating all your EQs. That’s pretty easy. Or maybe using heaps of bad reverb on the mix bus? That’s also pretty easy. If you asked Ian Shepherd, he might say trying to make everything loud unravels mixes.
Your turn: What do you think is the easiest way to unravel a great mix?