There are a lot of ways to deal with this. I am not sure what DAW you are using, so I don't know if you can do sub mixing but here is 2 ways I deal with it...

1. Go & Grab Multi-Inspector Free and place it in your Master out. Submix your Drums, Bass, Guitars-Keys, and background vocals. This will allow you to see the frequency range of the 4 sub mixes, and you can then cut the vocals at the frequency they are masking at.

2. I treat BV like an instrument, so I am not "gentle" with them. Sub-group them & then roll of the bass starting at 150Hz & go up until they quit masking everything. Divide them into low-high range and then balance them between L-R with 1 low & 1 high per side. Pan them to 9:00 - 11:00 - 1:00 - 3:00 to spread them out but not to far. Place a light Chorus on the sub-mix to add a little motion to them.

This has worked for my a lot, and even if it was NOT what I was looking for it was a good starting position. Every song is different, but there are some basic ground rules to this stuff no matter what all the "arm chair mixers" say...including me!

Hope this helps!

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