How to Master a Compilation: Make Tracks From Different Sources Sit Together
Published · by Loopin
A compilation fails when track 4 is 4 dB louder than track 3. Pick one anchor track, bring everything else to it, and listen to the joins, not the songs.
Collect stereo mixdowns and note the problem children
Ask every artist for a stereo mixdown with the master bus processing off and a little headroom, around −3 to −6 dB peaks. If someone sends an already-limited file, take it, but mark it: you cannot turn a crushed file back into a dynamic one, so that track becomes the loud ceiling you match everyone else toward.
Open a sheet with one row per track: source, sample rate, rough loudness, and one word for the tone (dark, bright, boomy, thin). Five minutes of listing now tells you which tracks need a lighter hand and which need a warmer or brighter feel later.
Choose one anchor track and judge everything against it
Pick the track that sounds most like the compilation should: usually the best-balanced mix with normal dynamics, not the loudest. Master that one first and keep it open as your reference. Every other track is judged by one question: does it sit next to the anchor without the volume knob moving?
If the anchor is a trap banger and the next track is a piano ballad, you will not make them match in tone, only in perceived level. That is the goal. Compilations are about even loudness, not identical sound.
Master each track on its own, then match levels
Run each song through free online mastering on its own terms. Use the default feel for most, Warm for thin or digital-sounding sources, Crisp for dull ones. Previews and the loudness-matched A/B are free and unlimited, so audition two feels per track before you commit.
Then line the exports up. The default export lands at about −14 LUFS with a −1 dBTP ceiling, so most tracks arrive close together. Anything more than 1 LU off the anchor on a loudness meter, or audibly louder next to it, gets re-run with a different feel or fix the mix before you try again. Remember downloads are capped (1 per rolling 24 hours with no account, 2 with a free account), so plan a 12-track comp over a week.
Do the sequence test, not the solo test
Solo listening lies. Stack the finished files in running order and play only the last ten seconds of each track into the first ten seconds of the next. You are listening for jumps: a new vocal that is suddenly forward, a bass that vanishes, a hi-hat that suddenly hurts.
Fix jumps at the track level, not by pushing everything louder. A track that jumps 2 dB up is usually the one with more energy in the top end, so try the Warm feel or ask the artist for a mix with the hats down 1 to 2 dB. Our guide to mastering an album consistently covers the same joins for single-artist projects.
Leave gaps and fades to the sequence, not the master
Set gaps in your DAW, not in the master. A default of 2 seconds works for most genres; shorten it for tracks that segue and lengthen it after a quiet ending. Add fades only if a track ends abruptly, and keep them under 3 seconds.
Export the final set as WAV at the same sample rate, name them with the running order (01, 02, 03) and keep the anchor’s name in your notes. A neat file name saves a revision round when a label asks for track 7 again.
Know when to hand it to a person
Automatic mastering is a strong fast first pass for a demo compilation or a free download comp. It takes no creative direction and cannot repair a muddy mix or a distorted file. If the comp is going to vinyl, a label, or paying contributors who expect a human master, send it to a mastering engineer and use Loopin versions as the reference.
For anything else, run the track through the free masterer, check the joins, and ship.
Frequently asked questions
What loudness should a compilation be mastered to?
Match every track to the same target. Loopin's default export lands at about -14 LUFS with a -1 dBTP ceiling; stay within 1 LU of your anchor track.
How do you make songs from different artists sound consistent?
Pick one anchor track, master it first, then match the others to it by loudness and check the joins in running order.
Should I normalize all the files before mastering?
Not necessarily. Ask for mixes with 3 to 6 dB of peak headroom, master each one, then compare loudness. Normalizing a crushed file does not fix it.
How many seconds between tracks on a compilation?
About 2 seconds is a safe default. Shorten it for segues and lengthen it after quiet endings.
Can I master a compilation for free?
Mastering and previews are free and unlimited. Free downloads are capped at 1 per 24 hours with no account or 2 with a free account, so a 12-track comp takes about 6 days.