I've lost all my bass, please help me figure out why

[Audacious Quip]

Hello everyone. Here is the info on my system's setup, so you'll be able to help me once I describe the problem.

Head Unit: Alpine CDM-9821 [click for pic]

Speakers: Alpine SPR-694A 6x9 speakers (one pair) [click for pic]

And the speakers came with an inline crossover, since the speakers have the 6x9 cone and a tweeter in the middle. [crossover pic]

Now, here's the deal--- the speakers are installed in my pickup truck's doors, mounted to wooden panels. The crossovers are properly installed. The little bolts holding the speakers into the panel pulled out, so the speakers were kind of hanging loose in the door. The driver's side speaker was pretty much still in place, so I just turned my balance all the way to the left and used the system on one speaker for a day or two. It worked fine for a little while.

Then at one point, without changing any settings or anything, I noticed that my music lacked bass. There was absolutely no bottom end to the sound--- so I shut the whole system off and took the face off the deck until I could properly re-mount the speakers, which is what I did today. Now I have the speakers wired up again, and there is still no bass, out of either speaker. I checked (and fiddled with) all the settings on my head unit. Fade is all the way forward (and these speakers are hooked up as front speakers). My 6x9s essentially sound like a much smaller speaker-- almost like a cell phone ringtone. //content.invisioncic.com/y282845/emoticons/crying.gif.ec0ebefe590df0251476573bc49e46d8.gif

The only cause I can imagine for this is that the speakers may have got a little rainwater on them while they were loose. They are normally enclosed in a foam enclosure (you can see it at the bottom of the speaker pic). This was not properly covering the speakers while they were loose.

What's the problem here? Are the low coils in the speakers shot? Is the crossover somehow causing this? Or has something happened to the head unit? I don't think the speaker wiring itself shorted out at all. Please help.

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[jpexpc 10+ year member]

I never knew letting speakers just hang was a bad thing. I'm so glad I read this thread..............

 

[fasfocus00 5,000+ posts]

Are the low coils in the speakers shot?

that would be this issue.

 

[Audacious Quip]

Well, I found the problem. The speaker cone isn't free to move in & out.

The epoxy that holds the magnet in place is no longer holding. The magnet was able to move around just enough that the pole of the magnet is no longer centered in the coil. As soon as it moves away from the center, it sticks to the coil, immobilizing the cone.

The speakers are 5 years old. I should've mentioned that.

I'm going to make an attempt at re-adhering the speakers after carefully centering the magnet with set screws.

I never knew letting speakers just hang was a bad thing. I'm so glad I read this thread..............

So in conclusion, it had nothing to do with the rainwater. But I think it did have to do with the speakers being loose and getting knocked around.

 

[jpexpc 10+ year member]

So in conclusion, it had nothing to do with the rainwater. But I think it did have to do with the speakers being loose and getting knocked around.

Good call.