What is EQ mixing?
EQ mixing is the DJ technique of using the channel equalizers — typically low, mid and high bands — to blend two tracks by swapping frequency ranges between them, most importantly never letting two basslines play at full level simultaneously.
The classic techno transition is a bass swap: as the incoming track's phrase begins, cut its low band, bring the fader up, then at the chosen moment kill the outgoing low while opening the incoming one — the dancefloor barely notices the track changed. Mids carry most of the musical identity, so trade them gradually; highs add presence and can overlap safely. Good EQ mixing keeps the overall energy constant through a transition, which is why two-deck techno sets can flow for hours without a single audible seam.