i have an s4 and mostly just do 2 channel but sometimes i like using a third deck because it allows me to mix a little more quickly. i’m pretty new at this so i try to keep that to a minimum until i feel in control of the two but i’ve pulled it off a few times and really liked my results most of the time
Also evenly wears out your channel faders and knobs 
Good tip!
Also, it’s great if you have a mixer that has user configurable EQ points (DDM4000, X1600,…), based on the genre of music you’re playing you can configure the EQ to better isolate different sounds 
Thanks man! As well I remember there was a video posted over a year ago i believe with Ean doing a 3 deck mixing w/808 that can also shed light into this discussion. Its really about slicing the different tracks to cover your sound spectrum properly. Never overloading your Low,Mid,High’s together. And a common problem is actually pushing the volume up with the mix becoming “louder”. I say its a problem because when it comes time to strip the other tracks away, or letting 1 or 2 decks ride with no other layering support. All of a sudden your mix can sound thin, and you get that feeling of less impact.
80% of the total gain and “meat” of your tracks sit in the Low/Mid section (if you were to look at a 3 band EQ perspective).
Well i love mixing with 4 decks, 2 track decks, 1 remix deck and 1 deck for step sequencer. you have so many options that djing never gets boring.
I use all 4 decks in traktor, 3 track decks and a step sequencer deck, the third track deck comes in handy for carrying a loop throughout several tracks
I’ll use 4 channels, but rarely have 4 different sources.
Use Xfader for effects/EQ
I’ll use input 1+2 with the same source, then route #2 through the FX unit, move #2 to the other side of the Xfader so I can use the Xfader for the effects or the EQ.
Cueing without EQ
Sometimes I might be mixing #1, with the bass n treble turned right down, making it hard to beatmatch, so I’ll duplicate it on #2 and cue it with the headphones with no EQ. Quite often I end up mixing records I really don’t know and this can really help.
Yeah, I have only used 2 of four channels for a while. However I just got a bunch of a cappellas and instrumentals and had an idea for tighter mixes. Load one and 3 with instrumental and a cappella of the same song, and tie the decks together (you can do that so each manipulation affects each track equally on the pio ddj sz) and load 2 and 4 with the instrumental and a cappella of the same track, this will allow much more control over the mashup without having the swooshy sound of the filter (which is good sometimes but not all the time)
Also I am learning to scratch and I believe the 3rd deck will be awesome for scratch samples. I currently just load two hits in deck 3 and 4 and leave them for when the drunk girl comes up and distracts me while I’m trying to find the next song to mix. If the floor goes silent I slam 3 or 4 on.
i’ve been using 4 channels for at least 10 years now. its great to be able to have acapellas, extra baselines, etc playing over eachother.
I read on a Reddit thread about mixing house music that 4 channels are useful for this genre and I agree. Although most of the time 2 channels are quite enough for me, sometimes what happens is that the point at where you wanna throw in track B while track A is playing is actually quite close to the end of track B. But you wanna keep a loop of track A while letting track B play and introduce track C. That’s when I found it useful to have 4 channels.
I guess this doesn’t hold only for house music but in my usage that’s how it happened to be useful. I think that it’s because there’s a lot of groovy melodic lines in house as well as breaks since it’s kinda in a verse/chorus song structure. So you wanna keep the melodic groove going while not overlapping singers and not loosing the beat therefore having a playground of more than 2 channels is quite helpful.
Nope, never been able to juggle more than 2 decks without losing track of one
i have two cdjs on channel 2 and 3, and two 1200s on channel 1 and 2 of my nexus mixer, so yes - 4 channels come in handy
I quite often have 2 tracks mixing together for most of the track. I then need a 3rd for bringing the next one in, so I don’t have like 16 bars to load the track and cue it. 4th channel get’s used for a remix deck. A 5th is used for the FX return.
I tried messing around with 4 tracks (and even with 3 tracks) and it sounded like noise even though all songs were in key and playing very minimal parts.
I think its best to use the additional tracks (decks C/D) to prepare to come in so you aren’t hectic to load the next track when ones ends, such as in a 2 track setup. Like I like to use the 3rd track to set a 16 or 32 loop so that its ready to go when my current track is ending.
Also with additional decks you can do mashups on A/B decks, and when that mashup ends in a 4 deck setup you can have songs on C/D ready to go so you aren’t scrambling to load A/B.