Sound & signal
Crossover
A crossover splits a signal by frequency and sends each part to the speaker built for it — lows to the subs, everything else to the tops. Every club system has one, set for its own speakers.
In practice
Subs and tops are different boxes fed by a crossover. That is why bass and vocals behave independently in a room.
Nothing here is yours to adjust, and that is the useful part: when the low end sounds wrong in one part of the floor and fine in another, it is geometry and crossover alignment rather than anything on your mixer. Walk the floor, believe what you hear out there rather than in the booth, and raise a genuine misalignment with the engineer — a sub arriving out of time with the tops is audible as a soft, late kick and is fixable in thirty seconds at the rack.
2+
Ways the signal is split
The rack
Where it is set
Soft kick
What misalignment sounds like
Where these come from: How installed club systems are configured — conventional design, not catalog figures. For what we can measure, see the boxes on the low side.
Why it matters
It explains why the low end and the rest of the music can behave independently in a room. They are literally coming from different boxes in different places, so the bass can be even on one side of a floor and the vocals even everywhere, or the other way round.
It is also the reason the venue’s processor is not something to work around. The crossover point, the delay that aligns the subs with the tops and the limiting that protects both are all set together for that room, and a DJ pushing the low end is pushing against a calibration rather than a preference.
Frequently asked
Can I change the crossover from the booth?+
No. It lives in the venue’s processor and is set against its specific speakers, along with the delay and limiting that go with it.
What does a misaligned crossover sound like?+
A soft, slightly late kick — the sub arriving out of time with the tops. It is fixable in seconds at the rack and impossible from the mixer.
Do headphones have a crossover?+
Single-driver ones do not. Multi-driver models do, and it is one reason two pairs can present the low end quite differently.
Related terms
Sub stack
A sub stack is the group of subwoofers handling the lowest octaves, usually on the floor and often in a block or a line rather than spread out. It carries the part you feel more than hear.
Club sound system
A club sound system is the whole chain after the mixer: processor, amplifiers, subwoofers, main speakers and often delay or fill speakers, tuned together for one room by an engineer who is not in the booth.
Frequency range
The audible spectrum runs roughly 20 Hz to 20 kHz, and DJ mixers divide it into three: lows carry the kick and bass, mids carry vocals and most instruments, highs carry hats and air.
Multiband compression
Multiband compression splits the signal into frequency bands and compresses each separately, so a loud bassline does not pull the whole track down with it. Club system processors use it; DJ mixers generally do not.
Explore: Frequency detector · Sub stack · Club sound system · All DJ terms