Subwoofer question: Loud POP! (1 Viewer)

[Steve_Pannell]

I searched the threads for a similar problem but couldn't find anything so:

I was watching Wonder Woman Blu-ray and at one particular scene near the end of the movie

Spoiler

where Diana returns the lightning and kills Ares

the frequency was very low and very loud. There were 2 extremely loud pops from my subwoofer during this loud scene. I backed off the volume and replayed the scene and it didn't happen again at the lowered volume.

Did I just overdrive the subwoofer or what? How likely is it that I permanently damaged the sub?

Sub is: Polk PSW 350
Amp: Denon AVR-X3300W

 

[Clinton McClure]

I searched the threads for a similar problem but couldn't find anything so:

I was watching Wonder Woman Blu-ray and at one particular scene near the end of the movie

Spoiler

where Diana returns the lightning and kills Ares

the frequency was very low and very loud. There were 2 extremely loud pops from my subwoofer during this loud scene. I backed off the volume and replayed the scene and it didn't happen again at the lowered volume.

Did I just overdrive the subwoofer or what? How likely is it that I permanently damaged the sub?

Sub is: Polk PSW 350
Amp: Denon AVR-X3300W

Good morning, Steve. It definitely sounded like you bottomed out the sub’s driver. If it still plays fine, I wouldn’t think you did any damage.

 

[Robert_J]

Did it sound like this?



It it was just a tap when the voice coil hit the back plate, then you are OK. If it slammed into the back plate of the magnet then it will deform the coil. It's like stepping on an aluminum can just a little bit. The sides will buckle some. Same thing can happen to your coil's former. With a perfectly round former, you may have had 2 or 3 mm of play each way. Cones will not move in a perfect line as they all have some rock back and forth. If your coil now has a ripple in the formed, you "play" may be gone and your former will rub the pole at high excursions. Even worse, the wires of your coil can rub the top plate. If the insulation is rubbed off, that will short the coil and take out the amp.

My description is worst case scenario. In all likely-hood you just tapped the back plate slightly. If you watch some videos of people blowing up subs, you really have to try hard to physically destroy one. Overheating one is another story and that rarely happens with retail subs.

 

[Steve_Pannell]

Thanks guys.

Robert, my pop sounded like the very end of the video you attached except it was one single loud pop instead of a "woodpecker" sound like in the video. But the scene in the movie was a fairly quick explosion-like sound and it was done.