with which controller i could do this?

Can’t speak to Traktor, but I know roughly how you would go about this using VDJscript in Virtual.

You’d want a four deck controller with some extra buttons. You’d then map those buttons to “link” decks, so that one set of controls moved the levels for two decks. If you can map that with Virtual, I’m sure there is a way to do it with Tracktor’s mapping setup too.

Of course, on a more basic level, never underestimate what you can pull off with just two hands. With a little practice you can move around between controls pretty quickly to the point nobody would ever notice they weren’t linked.

So many different ways of doing this!

You don’t say what audio interface you are using, but I guess that its a 2 channel output (e.g. Traktor Audio 2) to your 2 channel mixer; and you don’t mention any DJ controller so I assume you are using the laptop keyboard/mouse. I’m also assuming that you are mixing externally through that 2 channel mixer, rather than mixing internally on the laptop. (If you are mixing internally with a DJ Controller not an external mixer then options 1 probably won’t apply, but there is still something in option 2 that may help.

Any midi controller will help make this easier but you can do this without any upgrades if you experiment a bit. The real clunky part is being constrained by the number of channels on the mixer and audio interface.

Option 1: This is limited and clumsy, but works. You can use the extra decks 3 & 4 and route through the same channels as 1 & 2 ( so that Decks 1 & 3 , and 2 & 4 each go through the same EQ) – clearly you have to manage volume (or at least manage the relative gain) on decks 3 & 4 on the laptop. If you can workout which mixer channel is going to trim the low frequencies together then simply either queue the loop on the deck that shares the mixer channel, or if the additional deck is set to be a remix deck then drag the loop to the appropriate matching deck. Doing this live could be tricky as you can’t listen or play the Deck 3 when the matching Deck 1 is playing out live.

Option 2: Similar to option 1, but more flexible is to use a filter effect to kill the bass (or whatever frequency). I think Filter:92 is best for this. Without going into details (see youtube) you can setup your 2 effect decks to be a high and a low filter. You can choose which decks you want to apply each effect to, then when ready hit the Effect enable button – this can hit whichever decks you want on any mixer channel, and more than one at a time.

However both of the options above suffer by being clunky to run decks 1 & 3, and 2 & 4 out of the same physical channel on your mixer. But it’s OK for the occasional mix, if you can practice or set it up beforehand. I went through this process recently.

Option 3: Change to mixing internally (in the laptop), and use a midi controller as you suggest. If you on a budget (say £150) then think about something like the Novation you suggested (good if you intend to use ableton alot at home) or an Allen & Heath Xone K1 MIDI USB DJ Controller (better for live work I think) using Traktor. If you already have a controller such as the Kontrol Z1 with your mixer controls then a Kontrol F1 would also be a valid flexible option for live work as it can be mapped to give you all the control over the additional decks.

Option 4: Change both the mixer and audio interface, for a combo. Not cheap I know but you’ll get good value. This is where I ended up – I bought the NI Kontrol Z2 to solve essentially the same desire to run primarily 2 channel with the other decks for loops, samples and the occassional third track. The S4 would also have done well, but I preferred the real mixer behaviour and separate mic channel. The balanced outputs and higher quality built-in audio interface has been a big step up from the Traktor Audio 2 for me. I’m getting significantly louder output with lower distortion from the same amp/speakers. But I had an easier cost decision as my Audio 2 had failed (1 min from the end of an Xmas Eve gig – got lucky there!) so moving to a 4 channel setup also needed to include an audio interface combined or separate, so I was getting over the £300 barrier.

I made some assumptions in replying to this query – so I may have missed the mark a bit.

Regards, MC.