After the audio system has been on for over 1/2 hr. I am getting clipping. I am able to replicate the problem with slightly higher than normal volume (not crazy, just louder.) I found that if I change the balance and fade to isolate the four corners that my driver's side front seems to be the culprit.

At first it seemed like the tweeter was the issue, but then I noticed that the woofer was putting out much less volume than the passenger side with equal balance. It is my theory that the woofer was somehow not recieving the power directed at it, and the tweeter is recieving ALL of it instead.

I am running Polk Audio Ex3550s and an MTX 5 channel amp that is rated at 75 watts RMS and the birth sheet showed 86 watts RMS at 14 volts. It is hard to believe that I over powered the speaker as I do not have the gains up, nor have I gone to full volume on the HU.

The real question I have is how do I test further. Is it the x-over? Is there an easy way to test the speakers themselvs? I did double-check all the connections and everything appears solid.

BTW -- This did work for several months.

 

Could you use a multimeter? Test before the amp, after the amp, and at the crossovers output posts, and do it on both sides...

That way you could see if it's the deck, amp, or crossover...

As for the question in your subject, the easy test for a blown speaker is to grab a 9v battery and touch it to the terminals...if it doesn't move, consider it blown

Now, if it's just significantly quieter and you checked the electric stuff, it's probably just a loose seal somewhere...Whenever I get one side more quiet than the other, the seal is usually the culprit.

Oh yeah, did you check to see if some wire jiggled out of place?

 

Great info. Thanks Bombrman!

I have a multimeter. I assume I am looking for VDC. What kind of range am I looking for?

The speaker does seem to move so I guess I did not blow the coil, but I will keep the battery test in mind in the future.

How do I fix/replace a seal? Is this a serviceable item, or do I need to replace the speaker?

I did check ALL the connections and they were all very solid.

 

Sounds like it could be either a bad amp channel, where clipping causes lots of ugly sounds to come out of the tweeter, or you may have a bad woofer.

It's pretty unusual for a cross-over to go bad since they are passive components.

You can do several tests:

1. Swap the speaker wires on the amp and listen again. If the problem stays with the speaker, bad speaker. If it stays with the amp channel, bad amp. (or maybe bad HU output)

2. Disconnect the drivers from the cross-over and test each one with an ohm-meter. A 4 ohm driver will usually measure between 2.5 and 4 ohms. If you get a good reading and with the ohm-meter connected, push the woofer cone in & out some and see if the meter fluctuates wildly. It may change slightly since you generate electricity when you move the cone, but if it jumps around a lot you may have a bad voice coil or leads.

3. The 9-v battery test works, but you need to be careful with tweeters, you could possibley put about 20 watts into a 4-ohm speaker. Woofers would be no problem though. You should hear a single loud "click" when you touch the battery to the speaker (assuming you don't wiggle the connection)

4. Check the woofer by carefully pressing on the cone and moving it in and out. Make sure you move it straight in & out. If it makes any scraping noises - bad news.

When you say "replace the seal" I assume you mean the "surround" (the flexible ring that joins the cone to the frame). They can be replaced but usually only by a professional speaker repair shop. And it ain't cheap.

 

[QUOTE]Originally posted by modifry
3. The 9-v battery test works, but you need to be careful with tweeters, you could possibley put about 20 watts into a 4-ohm speaker.

 

If I may chime in, I had this problem with my passenger side components a few months ago. The system worked fine for 3 months, and then started to sound distorted and awful at medium+ volumes. Turns out that they constants driving and hitting bumps, made the tweeter wires come loose and touch each other....connection was not as secure as needed. Check for that as well.
Good luck!

 

This is fantastic info. Thanks guy!

I will try all these things this weekend.

NFR -- I did check all the connections to the tweeter and woofer and at the amp. All still solid.

bomberman -- If I understand what you are talking about, I did not use any weatherstriping. I re-used the stock speaker baskets by cutting out the back of them. The speaker is mounted very securely.

 

If all else fails try this.................try loosening the mounting screws that holds the speaker in your door panel and re-torque the screws evenly again. Sometimes if they weren't tightened evenly, they torque the speaker basket and don't allow the voicecoil to travel evenly into the magnet. If that doesn't work, you might have burnt the voicecoil to the point that it changed the impedance of the driver and it may have to be replaced. Good luck!

 

Good suggestion - it's usually stamped-steel speakers that can warp like this, which is why some more expensive drivers are cast aluminum - not as strong but more rigid and also less prone to unwanted resonance.

I had a home speaker woofer once that if I pressed on one of the 4 corners hard enough (while playing music) it would stop making the nasty noise. There was just enough compression in the gasket material between the front-mounted driver and the cabinet to allow the frame to flex, and pressing on it flexed it back into alignment. I ended up shimming the other 3 corners but it didn't last long - I think the voice coil was damaged and it quit soon thereafter.

 

[QUOTE]Originally posted by modifry
1. Swap the speaker wires on the amp and listen again.