subwoofer failure question

[pfschim]

this is only tangentially bass related.

I have my bass rig set up in the same room as my home theater system.

We have a decent 5.2 system (center, 2 sides, 2 rear surrounds, 2 subs) that has worked well for us for the past 6 years. The speakers are all upper quality Cambridge Sound Works stuff, nothing super fancy or audiophile/videophile, but decent, well set up and well calibrated.

So, one day last week I decided to crank up my bass rig (Mesa Walkabout running 500w @ 2ohms into a Mesa 12 and Mesa 15 ). The house was empty and I was trying out my new-ish Lakland 44-02 deluxe fretless at other than practice volume . Well, the bass/lows on this combination are really thick and deep and as I was playing all of a sudden I hear a terrible sound, a truly nasty rhythmic farting kind of sound.

At first I thought it was my rig and I was really bummed and confused. I had not played it louder than gig volumes.

Well, turns out that it's NOT my bass rig, but is my main home theater Subwoofer. My questions are:

1. is it possible that I fragged the speaker/driver on the sub because of the overpressure from my bass rig ?

2. is the farting noise more likely a blown or damaged driver, or the amp ?

2. is it possible to fix the subwoofer unit by simply replacing the driver with an appropriate replacement ?

any input from the combined collective intelligence of the TB community on this ?

thanks

[pfschim]

bump ... hmmmm... no one ??

[Diggler]

Usually the 'farting' sound results from overdriving the speaker. Have you tested the subwoofer with your home stereo system since then, does it still work?

Your speaker was probably way out of its league, but it might not be blown.

[lefty007]

Could be mechanical failure. The sound pressure maybe messed with a thin solder or component. . . A rhythmic noise will indicate the problem is in your amp, not the speakers.

[pfschim]

Originally Posted by Diggler

Usually the 'farting' sound results from overdriving the speaker. Have you tested the subwoofer with your home stereo system since then, does it still work?

yes, I did test it. I turned it off for a few minutes, then on again. It still produced the farting noise without any signal from the AV amp.

not sure what you mean by the "speaker out of its league" comment. The sub in question is (or was) part of my home theater set up and has been working fine for about 6 years.

Originally Posted by lefty007

Could be mechanical failure. The sound pressure maybe messed with a thin solder or component. . . A rhythmic noise will indicate the problem is in your amp, not the speakers.

ok, thanks for that. I was wondering about how to tell an amp problem from a driver/speaker problem. If it's the sub's internal amp, I'm not inclined to mess with it, or try to repair it.


In any event, I replaced the bad sub with another one ..FWIW a Velodyne DSP 12B. Sounds fine and did not hurt too bad

thanks

[Diggler]

I thought that somehow you hooked up your bass through your surround sound system.

[pfschim]

Originally Posted by Diggler

I thought that somehow you hooked up your bass through your surround sound system.

I can see why you might have thought that, but no, this question/post was only tangentially bass related because I felt like maybe I blew the home theater sub by cranking my bass rig in the same room.

In any event, I already replaced the av sub with a new one.

thanks

[Petebass]

Seriously, the amount of pressure exerted on the speaker by your bass rig, even when cranked, would be a fraction of what your sub endured when watching a movie. Explosions, gun shots, etc would all have more of a chance of damaging the sub that sympathetic vibrations from a separate speaker cab.

IMO the bass rig had no effect on the sub being damaged. At best it was a coincidence that your were playing your bass rig when the sub "died".