Speaker Distortion help!!!

I would check the signal line if everything is at 0db and not going into the red zone. From software over mixtrack to speakers.
What speakers are you using?

To understand the signal chain …

* Controller hooked up to PC, all settings in DJ software and drivers for controller up to date (especially the ASIO drivers if you are using windows)?
* Master output from controller into an amp (no info given here on make/model)?
* Amp into speakers (the amp/speaker combination is working correctly when hooked up to the PC output)?
* Signal path checked for 0dB throughout?
* Does the distortion appear in your pre-listen headphones?

You switch RCA cable on the amp when going from laptop to controller?
What length RCA cable are you using from controller to amp?
What sort of distortion are we talking about exactly, like overpowered or more like heavy humms, sound breaking up?

If the sound is coming in clear through your headphones we can conclude that the sound from the laptop into the controller is correct (cue is just pre-fade listening, so the same you would hear from the master if you opened the fader). EQ is pre-fader also (i.e. if you had your low EQ up too high causing distortion it would be audible in your headphones too).
The amp/speakers work fine when hooked up to the computer. Assuming only one set of inputs (switching cables to go from one source to the next), we can take those out of the equation too.

What does that leave? Faulty hardware in the master output section (summing amp) of your controller (as we already concluded that it should be fine post-fader per channel). Master output too high (best practice is to have your amp open full or at 0dB and control volume levels with the master volume on your controller, not to have your controller master output on full and turning down your amp to control the overall volume) is another option. Finally something in the cabling (either faulty cable, although this usually does not present distortion, just fall-outs and such or stuff picked up along the way (run an RCA cable next to a lighting dimmer pack and I promise you an awful sound for example).

Easy test is to grab another audio device with RCA out (old cd-player, cassettedeck, whatever) and hook that up instead of the controller. Play a tune, listen for distortion. If none, then it’s in the controller somewhere. If you get the distortion then too, it’s in the cabling or what the cabling runs next to.

Final test if it’s in the controller, is to take the controller and hook it up to another amp or active speaker and see if you get distortion then.

I know you’d rather have an “do this, then do that and fixed”-answer, but the truth is that in these cases going down the signal path trying to isolate the location of the problem is the most important but als most time-consuming step.

Hope that helps some.

Excellent point. RIAA correction actually adds bass too (they put less bass in the actual vinyl to prevent the needle from hopping out of the groove. I assumed that the amp was just an amp, without a preamp in it. But … assumptions being the mother of all f*ck-ups … bad move on my part.

It’s where you all run around a number of chairs one smaller than the number of circling people, while music is playing. When the music stops (abruptly) everyone has to sit on a chair, leaving one person standing. Thus correcting the group number. Issa simple, I would have thought you of all people would have gotten that.