Should I Leave the Limiter On the Mix Buss for Mastering?

Send both. One with the limiter, one without. That is the short answer, and the rest of this article explains why it matters.

The Problem With a Heavily Limited Mix

When a mix arrives with a peak limiter or heavy loudness processing on the master buss, the mastering engineer is working with a signal that has already been shaped by that processing. Transients have been caught and controlled. Headroom has been consumed. The dynamic envelope of the mix reflects the limiter's decisions, not just the mix engineer's.

That is not always a problem. Sometimes a mix engineer works into a limiter deliberately, and the limiter is part of how the mix sounds and holds together. In those cases, bypassing it can cause the mix to fall apart. Balances shift, elements that felt controlled become unruly, and the mix you approved in the session is not the mix in the file anymore.

This is exactly why sending both versions is the right approach. The limited version tells me what you were hearing and what you signed off on. The unlimited version gives me a clean starting point with headroom to work with. In most cases I can get where we need to go with the limiter off, and the master will be better for it. But not always, and I would rather have both options than have to ask for a revision after the fact.

What to Send

If you mixed without a limiter on the master buss, or with only light bus compression that is not loudness-focused, just send that mix. Leave the master buss processing in place if it is part of the sound. Bypass anything that is specifically there to control peaks or add loudness.

If you mixed with a peak limiter or loudness maximizer on the master buss, send two files:

One with the limiter engaged, as you heard it in the session. One with the limiter bypassed, at whatever level that produces.

The unlimited file does not need to be at a specific level. It does not matter if it is quiet. What matters is that the limiter is not in the signal path, so I have access to the full dynamic range of the mix.

If the limiter is staying in, a 32-bit float export gives the mastering engineer access to any headroom information above 0 dBFS that the limiter was catching, which a standard 24-bit file clips and discards permanently. It is a practical detail that directly affects what mastering can do with the file.

Master Buss vs. Individual Track Processing

This applies specifically to the master buss. Compression, saturation, limiting, or any other processing on individual tracks or groups is fine and should stay in the mix. The concern is processing on the final output that affects the overall level, peak control, or dynamic envelope of the entire mix.

As long as the overall mix output is not hitting or exceeding 0 dBFS, and there is no peak limiting preventing natural transient peaks from coming through, the mix is in good shape for mastering. Headroom at the mix stage is not something to be afraid of. It gives mastering room to work.

For more on headroom and true peak levels, see True Peak vs Inter-Sample Peaks and Mix Preparation and File Delivery for Mastering.