JL Audio f112 blown speaker?


I have/had a JL Audio f112 and I absolutely love it. About 3 months ago I changed my processor from a B&K Ref 50 to the new Classe SSP800.

About a month later my f112 started, for lack of a better term, started screeching, when I would play it. I have no idea what happend, but I unhooked the XLR connection and it would continue sporatically, even without any signal.

JL Audio was absolutely great. I sent it in and 5 days later a new one shows up at my door. Now after a month the same thing has happened with my new one.

I'm not playing them loud at all. I play video games, watch movies and listen to a lot of music.

Something is up and I am clueless what it is. It must be something in my system causing this. Any suggestions?
rshad0000
JPL,

4" is peak to peak - so 2 inch in and 2 inch out. This is the absolute maximum - it would probably sound even more distorted than 10% THD at those type of excursions.
One would have to drive this F113 to insane levels before hearing any distortion. As an owner I can promise you this.
The testing that is being done on these subwoofers are not real world. They do show what happens on a graph which does not mean too much to me. I would much rather listen to the sub in my own listening room and try to calibrate and integrate with the mains and room. The JL Audio has great features for doing this. Do we even know what excursions were taking place when this distortion was taking place?
Do we even know what excursions were taking place when this distortion was taking place?

The HT Shack Subwoofer test graphs are colored with a variety of measurements at various SPL outputs, all at less than insane levels. Many of the curves show what could hardly be called insignificant amounts of distortion.

If you look at an equal loudness contor plot of our hearing sensitivity then you will observe that the sound of 10% distortion will be much louder to our ears than an orignal 20Hz tone => because of our lack of hearing sensitivity at 20 Hz you hear the distortion louder than you hear the music.

Refer to the bottom of the page (last two plots) to see what Seigfried Linkwitz has to say about distortion at low frequencies.

Linkwitz suggests that 1% THD is the kind of distortion you ideally need in a sub - if you want to hear what is on the recording.
What I don't understand is the fact that all the reviews basically rave about this sub and yet they have this so called disortion in the way. I have tried everything in my power now to drive this F113 to the point where I should be getting distortion or cabinet resonation. I have a dedicated line and a Lessloss power cord on it right now so maybe that has something to do with the sub not distorting. I feel this sub is great for movies and outstanding for music. It controls the higher frequencies with precise accuracy ("very real musical bass")and zero localization.