JL Audio F110 Loud pop when pc unplugged ?


Both my F110 generates a really loud pop when the power cord is unplugged with the front power switch in the OFF position. Preamp in OFF position also.
Also loud pop occurs in the event of a power failure.
This sound is really scary.
Powering up seems OK, no loud pop.

If anyone has notice this, is there a way to fix ?
128x128terryakhan
Plate amps had a malfunction and after replacement the problem has disappeared.
I am very lucky because there is a JL service depot is in my area and replacement covered under warranty.
I did the work myself because if the high gloss finish should get damaged I am the one to be blamed.
Thank you.
The reason is likely with the way your power cord plug connection is made/broken to your electrical outlet-and has nothing to do with your unit. It seems your plug's ground may not be making a solid connection or your receptacle is faulty. I would recommend checking and cleaning each with particular attention to the ground connection. By any chance had you disconnected or floated the ground? You may be able to test this idea by simply using a $10 or $15 polarity/ground tester to start, at your receptacle.If things are ok try using any grounded extension cord and retest the receptacle on the extension cord. If all is ok you plug into the extension , listen a while and power down and wait 5 minutes. Capacitors, after having been warmed and played, start to discharge immediately upon turn off of incoming current with their energy dissipating mostly in the 30 seconds after turn off. I'm assuming your amp is connected to speakers of course. If there is no pop you may have confirmed the problem is related to the plug/receptacle interface. If so I would upgrade your power plugs; usually an easy worthwhile improvement for any power cord. If not lets discuss more. Good luck. Pete
You might want to call them up or email them, overnight should be plenty of time.
I like to thank you all for your responses.

Whenever I planned to do some work with the subs, I turn off the front ON/OFF switch overnight allowing the caps to discharge.

I had to unplug the power cords a few time because of re-postion and pc replacement.

An IEC to each sub. Balanced feed and no slave. The subs are powered down before I unplug the pc and volume setting does not make any difference.

My next test is to allow the discharge time for 40-50 hours before unplugging, perhaps overnight is not long enough.
I will post the results.
How do you have them connected? An IC to each one, or an IC to just 1 and make the other a slave? Also, balanced or se.? You can also try lowering the volume on the subs all the way and then unplug them.
I would not unplug the unit unless an electrical storm is coming, then make sure the unit is off and not in standby, and don't unplug it until a few minutes after it's been turned off, that has worked for me.
I had a pair of F212 in my system for a couple of years and never had any popping issues. I can’t remember if I unplugged the AC cord other than trying various cables to test performance.

Not to be rude, but why do you unplug the H110? It has a standby power so no signal shuts down electrical draw after a few minutes.

Great subs by the way, mine were impressive.
That should not be unless you are unplugging them while their caps are still charged, maybe? Does this happen after they've been off for say a few hours?
Is there an on/off switch? If so, try turning the sub "off" first and waiting at least a minute before pulling the power cord.