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I have dedicated lines, but why is this happening?

When my central air kicks on, I hear a pop through each speaker.

Now the odd part is, I just started hearing this recently. I never remember hearing it for the first several months after I had the dedicated lines installed.

I have made several changes to my system recently that has taken the transparency of my system to a level I didn't think was possible, but I don't think that could explain why I am just now hearing the pops. Or could it?

But the primary question remains. Why is the air conditioning popping through my speakers when I have dedicated lines.

Could this be coming back through the main bus bar ground in my panel?

What would fix it?

I obviously know crap about this stuff.
fiddler
bigdope9
3 posts
 
An additional suggestion: try measuring the AC voltage at the receptacle before and during the moment the A/C system is energized. Buy a plug-in AC voltage meter from Radio Shack. At the instant the A/C system activates, the high starting current of the compressor may momentarily drop the AC voltage at your stereo to 100 VAC or even less. If your gear already draws significant current, or your entire neighborhood is blasting their A/C systems, or you have the whole house lit up, the voltage may already be dipped. If the additional voltage dip is low enough, one or all of the pieces in your system may be generating the pop noise.
fiddler OP
581 posts
 
Thanks for the suggestion, Bigdope. I will try it and see what kind of drop I get.
fiddler OP
581 posts
 
Bigdope, I measured the drop and the drop was 119.4 v to 118.8. Not much.

But it does seem this symptom started with the onset of much warmer weather when summer started. Things will begin to cool off on Maui by the end of the month. We'll see what happens as things get cooler into November and December.
sean
6,231 posts
 
Fiddler: Did you try cleaning the ground connections / ground rod yet ? I'm curious as to whether this did anything or not.

Other than that, it's possible that the fan motor has some type of capacitor or "condensor" that is going bad. These typically help to reduce or absorb the turn on "transient" or "spike" that motors or generators produce on start-up. Don't know if your system has one of these or not, but it might be worth checking into. Sean
>

PS... Does this happen if you have everything disconnected from the amp with just the amp powered up and connected to the speakers ? You might try tracking down which component(s) it is coming in through.
fiddler OP
581 posts
 
Sean, I haven't checked my ground connection yet. I need to either try to find it myself or call the electrical sub that did our house.

I have not tried your suggestion with just the amp plugged in, but I will try that and then each component until I see if there is one offender. I don't guess there is any harm in the pop, but I think it is symtematic of another problem, i.e. the ground.

I will report back after trying the ideas.

Thanks all for your suggestions.
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