Can you under power a subwoofer?
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=82867
Printed Date: July 12, 2025 at 10:28 AM
Topic: Can you under power a subwoofer?
Posted By: jettagli03
Subject: Can you under power a subwoofer?
Date Posted: September 14, 2006 at 10:44 AM
Replies:
Posted By: haemphyst
Date Posted: September 14, 2006 at 11:42 AM
Sure. And be perfectly safe doing so. Electrically and thermally, NO you cannot underpower a woofer. If you cannot cause thermal damage to the voice coil, you are technically underpowering it.
Can you underpower and cause damage? Yes and no. If the woofer is in an incorrect enclosure, you can cause SEVERE mechanical damage to it, up to and including total annihilation, but is that related to the amplifier? No, even though you might be "technically underpowering" it.
Electrically, though, NO, YOU CANNOT UNDERPOWER A PROPERLY ENCLOSED WOOFER AND CAUSE DAMAGE, ELECTRICALLY. Feed the thing square waves, and as long as the continuous power being applied to the voice coil does not exceed the thermal capabilities of the voice coil, you will NEVER blow it. End of story. Even if you have a 500 watt amplifier feeding square waves to a 1000 watt woofer, if it blows, you were feeding it too much power. Again, end of story. EVEN THOUGH THE AMP IS "RATED" 500 watts, if the average power produced by the amp blows the woofer, you HAVE EXCEEDED the power capabilties of the voice coil.
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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."
Posted By: bj99
Date Posted: September 14, 2006 at 2:43 PM
haemphyst wrote:
Sure. And be perfectly safe doing so. Electrically and thermally, NO you cannot underpower a woofer. If you cannot cause thermal damage to the voice coil, you are technically underpowering it.
Can you underpower and cause damage? Yes and no. If the woofer is in an incorrect enclosure, you can cause SEVERE mechanical damage to it, up to and including total annihilation, but is that related to the amplifier? No, even though you might be "technically underpowering" it.
Electrically, though, NO, YOU CANNOT UNDERPOWER A PROPERLY ENCLOSED WOOFER AND CAUSE DAMAGE, ELECTRICALLY. Feed the thing square waves, and as long as the continuous power being applied to the voice coil does not exceed the thermal capabilities of the voice coil, you will NEVER blow it. End of story. Even if you have a 500 watt amplifier feeding square waves to a 1000 watt woofer, if it blows, you were feeding it too much power. Again, end of story. EVEN THOUGH THE AMP IS "RATED" 500 watts, if the average power produced by the amp blows the woofer, you HAVE EXCEEDED the power capabilties of the voice coil.
I agree with haemphyst 100%. If you act like an idiot it is possible, but if you put some thought into what you are doin then you wont blow the sub.
Posted By: xtremej
Date Posted: September 14, 2006 at 4:24 PM
Since you are fairly new to the site I'll throw you a link. This topic was discussed in depth in this topic. -------------
Posted By: jlord16
Date Posted: September 14, 2006 at 11:41 PM
The only reason damage is sustained from under poweing is from people setting the gains to full and attempting to "pump" their system resulting in a clipped signal from the amp, this isnt good for the woffer and this casues mechanicla damage, if your not a try hard and use ur equipment properly its usually fine to underpower subs
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Clarion DB36MP
Infinity Kappa Perfect 10"
Respone 800w Mono
ALPINE MRP-F250
*Custom fabrications*
Posted By: haemphyst
Date Posted: September 15, 2006 at 7:00 AM
djscustomz wrote:
I have noticed 9 times out of 10 underpowering a sub in a sealed inclosure which is causing severe clipping will cause the subs to be left in ruins but ported or vented it is usually and most often impossible to do......
This one here is a completely new spin I've never heard before, and a spin that makes NO SENSE whatsoever. What the hell are you trying to say? The enclosure has nothing to do with over- or under- powering a woofer, especially when referring to this thread...
jlord16 wrote:
The only reason damage is sustained from under poweing is from people setting the gains to full and attempting to "pump" their system resulting in a clipped signal from the amp, this isnt good for the woffer and this casues mechanicla damage, if your not a try hard and use ur equipment properly its usually fine to underpower subs
As I said, and has been said in threads over and over, IF your woofer blows, and it's attached to an "underpowered" amplifier, then the amplifier IS MAKING MORE AVERAGE POWER THAN THE WOOFER IS DESIGNED TO HANDLE. This is physics, and it cannot be denied! As the output of an amplifer gets clipped off, the average output power of the amplifer will increase, sometimes to well beyond what the amplifier is DESIGNED to produce, approaching an overpower situation.
If you were to take a 100 watt amplifier, and put it, for example, on the Eclipse SW9122 in my trunk, NO MATTER HOW HARD OR HOW LONG YOU CRANK IT, THAT AMP WILL NEVER, EVER BLOW THAT WOOFER. It simply can't. Even if the amplifer was producing 100% distortion, which is close to what a square-wave output is, at 200 watts, which is what the AVERAGE output power would be, that woofer will be perfectly safe in taking all of that dirty, clipped, distorted, nasty power. The woofer is capable of handling all that power, and whether the power is distorted or not, it won't be destroyed, no matter HOW nasty it might sound.
Now, take a 100 watt amplifer, and throw it on a 150 watt woofer, and do the same thing to it, yeah, it's likely gonna blow... BECAUSE THE AVERAGE POWER IS VERY CLOSE TO (OR EVEN SLIGHTLY ABOVE) WHAT THE WOOFER IS DESIGNED TO HANDLE. This is OVERPOWERED. The distortion didn't kill it, the excessive continuous power did.
I belive it was DYohn who said (1: I'm paraphrasing, and 2: I apologize to the actual poster of this phrase if it was not DYohn) "If low power would damage a speaker, then every driver in your car would be destroyed, just by turning down the volume." Think about that, and you'll realize he is correct.
This is a dead horse. Stop beating it. Underpowered amplifiers, properly set-up, cannot destroy a woofer, but driving any amplifer beyond its capabilites CAN cause that amplifier to produce more AVERAGE power than the potential load attached to it was designed to handle. ------------- It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."
Posted By: DYohn
Date Posted: September 15, 2006 at 8:18 AM
Yes it was me, and yes I agree.  ------------- Support the12volt.com
Posted By: Flakman
Date Posted: September 15, 2006 at 10:17 AM
Time to post this at the top of the forum and lock it as a sticky!!!
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The Flakman
I feel strange. I have deja vu and amnesia at the same time.
John | Manteca, CA
Posted By: xtremej
Date Posted: September 15, 2006 at 10:43 AM
Too little power.. is the heading....as a sticky...... I think . -------------
Posted By: Flakman
Date Posted: September 15, 2006 at 10:51 AM
xtremej wrote:
Too little power.. is the heading....as a sticky...... I think.
Thank you for pointing out that I have not read ALL of the stickys on this forum!!! (I would place an embarrassed smiley here...but the global policies at my job don't allow). Good call xtremej =) ------------- The Flakman
I feel strange. I have deja vu and amnesia at the same time.
John | Manteca, CA
Posted By: haemphyst
Date Posted: September 15, 2006 at 11:32 AM
Flakman wrote:
(I would place an embarrassed smiley here...but the global policies at my job don't allow).
Shouldn't you be working?
...Wait, shouldn't I be working?...  ------------- It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."
Posted By: Flakman
Date Posted: September 15, 2006 at 1:51 PM
haemphyst wrote:
Shouldn't you be working?
...Wait, shouldn't I be working?...
Well...I said I was at my job. I didn't say that I worked when I'm there  Of course...now it seems that everything works okay. This is especially embarrassing since I'm the Network Admin for the division. I must need sleep...or some Patron and a Pacifico!!! ------------- The Flakman
I feel strange. I have deja vu and amnesia at the same time.
John | Manteca, CA
Posted By: sparky3489
Date Posted: September 28, 2006 at 3:43 PM
Ok, all you disbeliever. Here is the end-all-be-all answer! NO!!! You can never underpower a sub. Why you ask? By turning my volume down, I'm actually underpowering it. If this were true, then subs would be blowing right and left every time someone turned their volume down! Thank you, and goodnight!!!
Posted By: haemphyst
Date Posted: September 28, 2006 at 4:42 PM
sparky3489 wrote:
Ok, all you disbeliever. Here is the end-all-be-all answer!
NO!!! You can never underpower a sub. Why you ask?
By turning my volume down, I'm actually underpowering it.
If this were true, then subs would be blowing right and left every time someone turned their volume down!
Thank you, and goodnight!!!
Wow... Thank you, Confucius...
Wasn't that said on the first page? Thank you for your wise insight, sparky3489... ------------- It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."
Posted By: Flakman
Date Posted: September 28, 2006 at 6:16 PM
Wow...this horse died a looooong time ago, but people still want to pick up a stick and take a swing. ------------- The Flakman
I feel strange. I have deja vu and amnesia at the same time.
John | Manteca, CA
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