Stupid guitarist thinks he's a soundman.

joeyp

I have just puchased a DRPX, Mackie sr1530z for mains and 1(for now) QSC hpr15 sub. also I use a Presonus studiolive mixer. Well any way, I have a few ?'s. First is hum and buzz. it seems that when the driverack is near the sub or power strip i get wicked buzz, very annoying...I put the drpx next to the sub and use the trs sends from the snake to the inputs on the drpx. and out from there to the sub and mains. at home the system kicks butt and doesn't but when we do gigs nothing but problems with buzz and hum. I'm very frustrated as I really want this to work for us. i'm also wondering about power requirements and using extension cords, also length of mic cables...the guys at guitar center told me to use the sends from the snake,I was just going to to use 3 50ft mic cables so I could keep the drpx out by the mixer instead of on stage...follow me? Next Question is about gain structure... please tell me an easy way to do this with this system. I have read most of the posts on it but i'm not there yet and I realize that this is a important part of getting my system to be the best it can be. If i'm not being clear enuff please let me know, the subject line does say stupid guitar player :shock: . thanks in advance and please help me!!!

Gadget

Your going to have to give a whole lot more detail if were going to find this problem...

Are you running a power cord from the amp rack to the mixer and all the FOH gear? They both need to be plugged into the SAME OUTLET!

Are the XLR to 1/4\" cables you run through you snake are BALANCED? ARE YOU SURE?

If your 100% SURE the above is correct... then you need to give us all the info you can.
Gadget

MDRussell

Wow. Just posted this as a topic and realized you had the same problem. At least i'm not alone!

Same issue here, different setup:

I recently bought a DRPX. I used it with seemingly no problem through EON G2's. I am now in the process of doing a concert series where I will be using 8 Mackie SRM 1530z stacks on top of 8 Mackie SWA1801 subwoofers. I used this setup once before and was baffled with some serious hiss coming from the speakers. As soon as I removed the DRPX from the chain and ran straight out of the board, the hiss disappeared. I have tried the same setup again in our warehouse with the same effect. I have tried loading all different presets with all different gain structures but to no avail. Its doubly frustrating because the 1530's have no gain control. ALL cables are balanced I am 100% positive, soldered em myself

Anyway, I am wondering if there is something dumb I may be overlooking or whether I need to try to send it in to DBX....problem is I want to use it in less than a week so I dont really have the time for servicing.

Gadget

This person has not returned.. I responded to your post...
Gadget

Dennis

joeyp has hum and buzz. MDRussell has hiss. these are different symptoms of different problems. Is hum/buzz an accurate description for joeyp and hiss an accurate description for MDRussell?

Dennis

Gadget

I noticed that, and I think that one has a ground loop issue and the other a gain structure problem...When I use a cheap mixer... BEH/Yamaha MG/ Mackie...then the higher the master outputs need to be the more HISSSssss is in the mix...you need to make sure that the individual channels are optimized as far as signal to noise ratio... I.E. the channel fader @ unity... and with the PFL engaged... the signal on the individual channels @ or above -0-vu on the master output meters (but with at least 6-10db of headroom...) THIS is where the noise (hiss) is induced.

Could be that the load of driving 8 cabs is causing a draw on the DRPX, but I have to believe it's a gain structure issue...or a noisy console...I know when I drive the BEH disco mixer setups...if I end up anywhere near unity on the mixer masters that the HISSSsssis intolerable...drive the individual channels harder, and the masters less...
That's My $.02 worth...
G