Got in my car today, turn on the tunes and my sub woofer is not working. (newly installed 3 weeks ago) Return to the installer and he says. Yup you blew the sub woofer, I can smell it. (I couldn't smell anything) Anyway, he says "If you play certine types of Music, IE. Hip Hop with certine bass frequency, poof blows the speaker. (I don't listen to hip hop, strickly Rock n Roll)
But I don't understand, if you have the correct amp with the correct speaker why would any music blow it. Isn't that why you get a sub, so you can crank it up a bit.
Am I getting BS'd here. I paid him $680, for custom box, amp, sub and install. (He is comering it under warranty, but hey, I don't want it to happen again.) Any Ideas guys.

 

The only thing I smell is BS.....

I mean, yeah it is possible, but it should take a lot to blow a good sub. As far as the cetain frequency theory, if they sold and installed it and now say that you can only play certain types of music I would be asking for a refund.

What sub, amp and kind of custom box?

 

Yea thats bs because some rock music will play the same frequency as a hip hop song would. It could have been just a bad speaker from the factory.

 

I have amp= Total Sound and Audio, 500 watts RMS
Speaker= 12" MMATX
Box= Custom enclosure, down facing with Air Space

 

not necessarially............

 

 

in general, there are two different ways to "blow' a speaker.

1. mechanical: This is caused by overexcusion of the speaker causing physical damage to the speaker by ripping the surround, the spyder, or other phyical damage to it. This can be caused by many different things. Examples: overdriving the speaker, a poor or incorrect enclosure design, poor placement of the sub enclosure (such as floor firing the sub but not allowing enough room for the driver excusion so that it hits the surface), a poor quality amp that doesn't provide enough damping control of the sub, a poor quality amp that introduces too much distortion into the signal to the sub, lack of use of a subharmonic filter, and other countless reasons.

2. Thermal damage: This is done by overheating the voice coil and the windings themselves will burn and/or the adhesive holding them melts allowing them to loosen away from the driver.
This problem is typically caused by running too much power for a sustained long amount of time for a particular speaker. Example - running 1,000 wats RMS power to a speaker rated at 125 watts power handling capability at high volumes for hours on end, incorrect set-up of the amp to allow clipping levels to be attained, and a few other reasons.

If your installed said he "smelled" that you blew the sub than you probably burnt the coil - it's a distintive smell.

Surprising to most people, it's also actually much easier to blow up a speaker by not running enough power to a speaker rather than too much power. The reason is that if you don't have enough power in the system and you want to turn it up to louder volumes than yu keep turning up the volume control byt the amp runs out of power and you than drive it into clipping and distortion levels - that will blow a speaker very quickly. On the other hand, a more powerful amp will allow you to attain high volume levels well before the amp goes into clipping and distortion so the speaker is safe. Speakers hate clipping and distortion more than anything else - it's their arch enemy. I actually took speakers - 5.25" components rated for 75 watts RMS power handling and throw a 500 wpc channel amp on them and cranked them up to max for about 2 hours with no problem. After letting the voice coils cool down I than hooked them up to a basic HU only and was able to blow them in the first 5 minutes of use. Like I said, clipping and distortion are not good things for a speaker!

Your installer saying that certain types of music are bad for speakers is pure BS. Certain types of music may be bad for my EARS, but not for a speaker. A speaker is just pushing air back and forth based on an electronical signal from the amp. Either the speaker recieces an electrial pulse to the voice coil causing it to move or it doesn't causing it to return to it's "home" position. It's nothing more than an electromagnetically controlled air piston and it has no clue what type of music it's reproducing so that was a seriously stupid comment by your installer.

Depending on the quality of the sub and the amp (lets assume for the moment they are good quality) than I'd first:

1. check the amp gain levels and see where they are set. Please don't tell me the installer cranked them to MAX setting.

2. Check for proper box design for the specs of the sub AND that it's completely airtight (unless it's a ported enclosure - which overall is nowhere as good as a sealed enclosure for controlling the movement of the sub and for power handling)

3. check that any "bass boost" or bass control on the head unit or other signal processing devices are not turned on and cranked up.

after replacing the sub, I'd strongle suggest the addition of a subharmonic filter into the system

There is always the simple possibility that the sub was defective from the factory causing the problem although again if the installer "smelled" something than 99% sure you fried the voice coil somehow. You need to figure out why or else you will do it again with the replacement sub

 

you have to have the widest range of replies. they are either super informative and helpful or just... well just like this!!! argh!

edit:
ok...you redeamed yourself

 

Yeah, you are right. (BarryK) I guess what I meant was if installed right and set right with the right power and enclosure and the user knows how to crank it without overdriving the sub then it "should take a lot to blow a good sub" LOL!!!

A lot of variables do come into play.

 

well, just keeping you guys on your toes..........

 

Thanks alot guys. Especially BarryK, very detailed.
Sounds to me the bottom line is there was nothing I could have done to blow the speaker, it's all based on the proper install and set up.
Again thanks

 

Whats a subharmonic filter

 

Well..... I guess what I am trying to say is that if you did not have it up way too loud then yes, you probably are correct...
It is difficult to say but much of it is based on proper install and setup.

If installed and set up correctly, common sense should tell you that you are harming a speaker with distortion. What I did notice is that you list the enclosure as a downfire, that makes it harder to notice when the speaker is over-driven (or under-driven).

 

A filter that cuts off frequencies below 20 hz. Some I have seen are adjustable up to 50 hz. It filters out inaudible frequencies and saves the woofer from over excursion.