At rehearsal this weekend, I was getting some wicked crackling in my amp. When I turned it up, it was nasty. Thinking it was my amp, I went through a monitor and got the same thing - nasty popping and crackling. I turned off the lights, thinking it was something in our light rig or overhead, but no difference. After trying to isolate and test everything, including swapping the battery on my bass, I was stumped. It made no sense.
My signal flow-
G&L bass >DI > Mixer > monitor & mains
DI parallel out > Amp
The crackle occured when the bass was in the amp, the bass was DI'd to the board, and when the bass was plugged straight to the board. I walked over and plugged into the guitarists rig - no noise. That made me think RF noise in my corner, and I noticed the computer near the mixing board.
The solution? Unplugging the computer from the digital mixer. Why? I'm not sure, but the instant the firewire was pulled, it stopped crackling everywhere - monitor, amp, mains. I don't fully understand how that affected my amp output was affected when no signal came from the board, but I'm guessing the firewire was unshielded and throwing out huge amounts of RF noise. I was near enough to pick it up in my bass pick-ups.
My signal flow-
G&L bass >DI > Mixer > monitor & mains
DI parallel out > Amp
The crackle occured when the bass was in the amp, the bass was DI'd to the board, and when the bass was plugged straight to the board. I walked over and plugged into the guitarists rig - no noise. That made me think RF noise in my corner, and I noticed the computer near the mixing board.
The solution? Unplugging the computer from the digital mixer. Why? I'm not sure, but the instant the firewire was pulled, it stopped crackling everywhere - monitor, amp, mains. I don't fully understand how that affected my amp output was affected when no signal came from the board, but I'm guessing the firewire was unshielded and throwing out huge amounts of RF noise. I was near enough to pick it up in my bass pick-ups.
