You take over, you match the previous DJ's level, and somehow it sounds smaller. This is the most common technical problem in DJing and almost nobody explains it, because it is invisible on the mixer.
Sound passes through several stages between the file and the speakers: the track's own mastered level, the channel gain, the channel fader, the master. Gain staging is making sure each stage passes a healthy signal to the next without running out of headroom.
Music has peaks — the transient snap of a kick or snare — sitting well above its average level, and those peaks are what the ear reads as impact. Clipping chops them flat. You lose the impact and gain distortion, so the mix becomes simultaneously harsher and less powerful.
Records are mastered at wildly different levels. An older release can be noticeably quieter than a current one, so identical gain settings produce a volume drop mid-transition that reads to the room as the energy falling out. How old is the music DJs play? found that about 5% of played tracks are ten years or older — a small proportion, but exactly the ones most likely to be quieter.
Fix: set the gain per track while cueing, every time. It becomes automatic quickly. Some DJs also normalise their library's analysis so the software's auto-gain does more of the work.
Peaks in the yellow, master at unity, gain set per track while cueing. A clean signal at a modest level beats a hot one every time, and the engineer will like you.
Setting the level at each stage of the signal path — track, channel gain, channel fader, master — so nothing is clipped and everything has headroom. Done properly every track hits the mixer at a similar level, so transitions do not cause volume jumps and the master stays clean.
Usually because it is clipped rather than quiet. Pushing into the red flattens the peaks, and peaks are what give drums impact, so a distorted set sounds smaller and more tiring even at the same measured volume. It can also be track-level variation: an older or quieter master needs its gain raised to match the rest.
No. The red means the signal is clipping. On a club system this is worse than useless, because the house limiter will reduce your level anyway, so all you have added is distortion. Aim for peaks in the yellow and let the venue's engineer set the room volume.
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