Can someone explain this?

[orangecat]

In the video i have 2 12 inch woofers from an old set of speakers that pretty much where garbage. The woofer without the dust cap has holes in the surround so i just removed the dust cap and decided this was a woofer i was just gonna play around with but the other one that is still good has nothing wrong with it. When I play certain frequencies (29hz and above) with allot of power the right woofer moves erratically.

 

I don't know why this happens and I don't think removing the dust cap would really do that. At first i thought it was the amplifier but it doesn't seem to be or at least if it is I can't really test it without an oscilloscope because the only other speakers I have that can handle this kind of power would easily be damaged mechanically.

 

BTW the woofers are wired up correctly and they are playing a mono signal so they shoudl be moving the same but they aren't.

 

(The video is loud, you've been warned)

[Mug]

That is the loudest video I've experienced

 

It frightened me, what with the noise of this profane music.

[Lays]

Probably because air is going thru where the dustcap would normally be, when air is not supposed to go through there

[orangecat]

That is the loudest video I've experienced

 

It frightened me, what with the noise of this profane music.

Sorry i shoudl have put a disclaimer that it was loud.

[orangecat]

Probably because air is going thru where the dustcap would normally be, when air is not supposed to go through there

It won't happen until a very particular power level and frequency. If I play a 20Hz sine wave and give it about 100 watts it's fine but as soon as i got 29Hz it starts jumping around.

[Guest]

It won't happen until a very particular power level and frequency. If I play a 20Hz sine wave and give it about 100 watts it's fine but as soon as i got 29Hz it starts jumping around.

 

All depends on the resonant frequency of the driver probably. The dust cap indeed serves acousti-mechanical purposes in most drivers that have them, not just keeping out dust.

[orangecat]

All depends on the resonant frequency of the driver probably. The dust cap indeed serves acousti-mechanical purposes in most drivers that have them, not just keeping out dust.

It was only a really thin paper dust cap i have a hard time believing it would affect the woofer that much but i could be wrong.