PA/sound system help?

Question

This is my system

Furman Power supply

32 Channel Behringer Mixer

Alesis Reverb

(2) DBX EQ'S (one for mains and one for band monitors)

1 DBX compressor

1 Rane Crossover

(1)Behringer 2400 amp (Monitors)

(2) Crown XTI 4000 amps (Mids/Highs)

(1) QSC EX4000 (Subs)

(4) JBL Jrx 125 mains

(2) JBL Mrx 518 dual subs

(4) Yamaha Monitors

As you can see its a intermediate setup, the problem I've been having is cabling it together the rack system, I bought about 20 Patch cables (Low-z) they are different colors so that I can tell each connection apart, but when I try everything together im getting no signal or sometimes very low volume. Would I need Hi-z's for my application? Also can someone please tell me the best way to set up my rack gear (order, tips, etc.)

Answer 1

No, it's not your patch cables. If you have high impedance signals running across a low impedance cable, they remain high impedance, and you're not going to worry about impedance mismatches at audio frequencies all that much anyway, unless you have a mile or more of cable in there.

I'd rig up something really simple.. try feeding a line level signal (from a tape deck, iPod, etc) directly to your preamp, and ensure you have a no problems there (you should keep a box full of at least one of any possible cable handy at all times... I know right where that dual 1/4" to stereo 1/8" cable is, I could find two or three in five minutes... and this is before I clean up my home office/studio).

Then, work it back your board, ensuing you don't have your input levels set for mics on line-level inputs, ensuring you don't have anything muted or soloing (it's surprising how many buttons get pressed when a piece of gear is moved and then set up), check the output level settings, check for activity at your VUs, etc.