Fact or crap, "under powering a sub will destroy it"?

Question

CRAP!!!!

Yes, I'm bringing this up agian, but for a good reason. Education. After all knowedge is power!!!

ANYONE who says "under powering a sub will destroy it" is holding on to a myth.

If I turn my volume down, I'm actually "underpowering" my subs. Low volume, low power.

People are confusing "clipping" with "underpowering". THEY ARE NOT THE SAME THING!!!! Clipping and over powering is what hurt subs and is the exact same thing.

Clipping is when someone tries to over compensate a low powered amp by increasing the sensitivity level (adjust the gain to a lower voltage input) to get more power out of it.

The gain control is a device used to "match" the volts RMS coming from the source.

Here is a guide that will help you set the gain correctly http://www.datafilehost.com/download.php?file=6d26c621

You'll need a multi-meter (AC voltmeter), Microsoft Excel and a way to burn an audio CD from an MP3.

This has been a public service announcement.

jejgop seems to be hanging on to the myth.

See what this guy wrote, he explains it VERY well. http://www.bcae1.com/2ltlpwr.htm

"I think where this comes from is some people say that using an amp with too low of power can destroy speakers. This is especially true of multi-way speakers with tweeters."

Nope, still false.

Well M V, this is true to a point. It depends on the intensity of the bass boost used.

Answer 1

oh it is total crap, i think the at the very core of the myth is the the lack of differentiating between clipping and under powering. when a amp is smaller than ideal, it does not automatically mean there is clipping, in fact there is no more a chance of clipping with two small a amp then there is with too large a amp provided they are run as they are intended at the rated wattage. people are simply "power greedy" and that is truly what blows speakers, they play with the gains not as they were intended as a result clipping, and blown speakers,
to all the knob nuts gain tweeking car install wanna be's out there, don't blame too little power for your mistakes.

Answer 2

For the record Sparky sorry for the delay in this responce (i'm currently in Afghanistan) but when I made that comment on one of your recent public service announcements I should of been more clear... i was refering to my friend using the BASS booster "located on the Amp" and was refering to that as underpowering damage to speakers... causing clipping. Also to answer the recent question posted about the bass booster on the deck... if you arnt running an amp to the sub and the RMS power output of thew deck is low (usually 14 to 16X4 RMS) and you turn it up all the way in order to hear the bass hit chances are by underpowering you are delivering realy poor power to the speakers and that crackling you hear can really damage ur speakers.

Answer 3

I think where this comes from is some people say that using an amp with too low of power can destroy speakers. This is especially true of multi-way speakers with tweeters. The tweeters have the lowest power handling capability and clips will send high frequency power to the tweeter. Woofers are less suseptable to this but not immue. Clipping causes the RMS power of the signal to increase, putting more power into the voice coil at the same voltage level. Also, when an amplifier clips it looses control of the cone and excessive excursion can occur, possibly damaging the voice coil as it hits the back of the magnetic structure. Most modern high performance woofers have extended bump plates to eliminate this problem but old/cheap woofers don't have this feature. Typically also, the power handling of a woofer voice coil is enough to handle the extra power delivered at clipping.
So no, playing a sub at low volume levels will not damage it. Driving it to high sound pressure levels with low power amps possibly can.
Adjusting the gain to assure the sub will never clip may not be getting the most from the sub. Depending on how the music is recorded, the bass can peak out at 0 dB or -10dB. If the sub is adjusted for the worst case scenario you could only get 1/10 the sub power out of that best case CD.

Answer 4

yeah dude i totally agree. I have a 12" Dual Sub and my parents won't let me get an amp so it feeds off the power from one of my rear speakers. And its awesome bass for no amp. Of course it doesnt hurt them.

Do you think it is ok to mix the power of the rear speakers and combine them into one sub?

Answer 5

This is just me but I thought that bass boost was for turning up the bass at low volume and you turn bass boost back down when you want to play it loud. I could be wrong let me know what you know about bass boost.

Answer 6

Ya know, i don't understand how this "underpowering subs will damage them" myth got started anyway. I've never in my life heard it until I came here and I've been around car audio most of my life and have been installing for about 4 1/2 yrs.

Answer 7

It will only blow the sub if you use a compacitor to make up for the extra wattage the system needs. Wire up 3 compacitors in series and you won't even need a battery.

Answer 8

it is simple if you can not under power a sub/speaker then you can never turn the volume down.....

Answer 9

Please do add that BASS BOOST does damage subs tho, as it forces subs to overextend exceeding both mechanical and thermal capabilities, alot of people don't realize this.

Answer 10

Dont worry about it