There's a failure mode specific to remote projects: the drums are tight, the bass is in tune and in time, the vocal is good, and the song still sounds like a collage. Four right answers that don't add up. Which makes sense once you say it out loud - every part was recorded in a different room, at a different mic distance, on a different day. Nothing in the signal chain has ever heard them together.
In a studio the room does some unifying for free: everyone leaks into everyone's mic and the whole recording shares one acoustic fingerprint. Remote sessions don't get that. The standard substitute, for about fifty years now, is a compressor across the whole mix.
Why it works
Put one compressor on the master and it reacts to the sum. Snare hits, everything dips a hair; between hits, everything swells back. Fractions of a dB, but now the guitar's level is moving because of the drummer, the way it would have physically in a room. That interdependence is the thing people call glue. It's not EQ, it's not loudness - it's the parts finally reacting to each other.
Settings
Drag Glue from Audio Effects onto the master track, last in the chain. It's modeled on the SSL-style bus compressor, and the classic settings are classic because they work:
- Ratio 2:1. The gentlest available. The bus is not where you do dramatic compression.
- Attack 10-30 ms. Slow. The transient of each drum hit gets through before the clamp; fast attack here flattens the punch you worked to record.
- Release on auto, or 0.1-0.4 s. Fast enough to reset between hits, slow enough not to pump.
- Threshold: lower until you see 2-3 dB of gain reduction on the loudest sections. Stop there. This number is the whole technique. At 6 dB the mix audibly breathes and gets smaller instead of tighter.
Bypass it on a chorus to check. With it in, the parts should feel like they're leaning on each other; without, faintly like a rehearsal. If bypassing makes everything sound bigger and more open, you overdid it - back off the threshold.
Two mistakes to skip
Doing it too early. The bus compressor reacts to balance, so every fader move after it changes how it behaves. Set it when the mix is close to done. In a shared session there's a second reason: the master chain belongs to everyone. Changing it mid-week changes what the whole band hears. Treat it like the rehearsal room PA - you don't rewire it without saying something.
Using it to rescue a limp mix. If 2-3 dB isn't binding things, more threshold won't either. The looseness is usually balance or frequency overlap, and the compressor can only glue parts that already fit. Fix the EQ first, come back, and suddenly the same settings work. Annoying, but that's mixing.