Here's the scenario: PA system with guitar effects boards and vocal mics attached. The volume is up on the PA. One of the effects boards is attached to the PA and plugged into a power strip that is on. I was asked to pull the cord out of the power strip. I didn't - I shut the power strip off. There was a small pop (and yes, ANY pop can damage the speakers - I know this!). I got yelled at for being stupid. My understanding was that switching the power strip off was the exact same thing as pulling the plug (meaning, there would have been a pop if I pulled the plug out, too). However, my partner tells me no - the pop was caused by the actual snap of the on/off switch on the power strip. I KNOW the right thing would have been to turn down the volume on the PA before doing anything, but let's not go there. Can someone please let me know if this is a fact or an assumption? Would there still have been a pop if I pull the cord out of the strip if the volume was still turn up on the PA head?
I assume the FX box was the only thing plugged in to the power strip? If not, the two situations are not comparable.
A well-designed mains switch will break the power more cleanly than you pulling a plug out of a power strip, so should result in less arcing and potential noise. IMHO using the switch is the correct option. A cheap mains switch with a poor trip operation might be worse than you pulling a plug, provided you pull plugs very quickly.
A well-designed mains switch will break the power more cleanly than you pulling a plug out of a power strip, so should result in less arcing and potential noise. IMHO using the switch is the correct option. A cheap mains switch with a poor trip operation might be worse than you pulling a plug, provided you pull plugs very quickly.
Thanks, DF96! Another FX was also plugged into the power strip, but the guitar tuner on that FX board was shut off, so the power (or at least the sound) to the PA head was interrupted (i.e. no sound from this guitar would be heard if it was played). The FX that he asked me to unplug does not have an on-board power on/off switch and no tuner, so it was hot. And, my thinking it that there would have been a pop if I pulled the plug as well as a pop if I turned the power strip off.
I know I am being a nit-picker here as my parther should have turned the PA volumes completely down before telling me to unplug something. Plus, the pop was not major - most people would have not even noticed. And this is not really about equipment damage - this is all about me being wrong, and him being right.
I know I am being a nit-picker here as my parther should have turned the PA volumes completely down before telling me to unplug something. Plus, the pop was not major - most people would have not even noticed. And this is not really about equipment damage - this is all about me being wrong, and him being right.
OOPS - I meant that the guitar turner was turned ON (not shut off!). When the tuner is ON, it shuts it off from power to the head.
Pulling the plug from the wall disconnects the ground connection before the dc rails collapse to zero, which is probably what makes all the difference.
As far as the switch begin a "clean break", the spark you see when you pull the plug is the inductance of the circuit keeping the current flowing until the energy is dumped into the switch. The switch can't break the circuit any quicker than the plug will, because the energy has no where else to go. However, the plug may make and break the connection several times as the brass contacts slide against each other and this will make a lot of noise, but it won't make a "pop" through the speakers but rather much higher frequencies.
As far as the switch begin a "clean break", the spark you see when you pull the plug is the inductance of the circuit keeping the current flowing until the energy is dumped into the switch. The switch can't break the circuit any quicker than the plug will, because the energy has no where else to go. However, the plug may make and break the connection several times as the brass contacts slide against each other and this will make a lot of noise, but it won't make a "pop" through the speakers but rather much higher frequencies.
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