Using Traktor S2 just for effects in club

I am sure there is a techie or someone that has access to the inputs on that unit (they are, as opposed to 99% of the mixers, not on the back but on the bottom of the unit if I am not mistaken. This is a mixer you would typically find behind a bar in a 19″ upright rack. If it’s fitted flat, you should easily be able to reach the inputs from below (cabinet door, access panel or something?).

I don’t think any self-respecting place will build-in their gear in such a way that they can’t get to the business end of things quickly in case something goes wrong.

About the FX use I am not 100% sure at what point in the routing the FX are added in Traktor. I think that FX only work when in internal mixing mode, but that won’t work with CDJs in HID mode as the sound of each track will come out through the CDJ sound cards.

I might be wrong, so hopefully a recent Traktor user has experience with this issue.

Well it could work if you used and external soundcard with it, but then you’d have to disconnect the audio of the CDJs and run those leads into your external sound card. In HID mode without an external sound card, the DJ software will send the sound from the playing track to the corresponding sound card in the CDJ.

The X1’s don’t have sound cards, so those are always used with either a USB mixer or an external sound card running two stereo channels into a traditional mixer (enter the accessibility issue in this case).

Again I am not totally sure where the software adds the FX to the sound in the routing, but usually that is done post (channel) fader and when you do HID, the channel faders in the software are not functional. Hence my thinking that it may not work the way you suggested in the OP.