For the last time, PLEASE: clipping does NOT blow speakers/subwoofers

[PV Audio 5,000+ posts]

but we are talking about underpower a speaker at the moment, pay attention

You cannot, under any circumstances blow a speaker by giving it less power than it's rated to. It just can't happen.

 

[PV Audio 5,000+ posts]

****, I didn't think this shit would be 10 pages. Y'all have fun, gotta go to class.

 

[audioholic 5,000+ posts]

But it really isn't. I understand that the logic is a bit semantically based, but clipping occurs in nearly every realm of electronics / anywhere you have a signal. You can just as easily overdrive an 800wrms sub with an orion 1200d as you can overdrive that same 800wrms sub with a 800wrms amp that is clipping fully. Saying that clipping kills speakers simply is not true. Again, I'll bring up the tube amplifier example which are made to clip purposely, but they don't destroy drivers.

Sure, clipping occurs in nearly every electronic circuit. So does this mean if you are constantly taking small leaps, you can safely jump off that skyscraper as well? If you can jump up and down all day long with no ill effects, can you say jumping never killed anyone?
'Underpowering kills speakers' was a saying made popular years ago by people being lazy (myself included). Instead of explaining that people had a tendency to buy an undersized amp and then clip the hell out of it to get the output they desired from the speaker, we all just coined the phrase that undersized amps kill speakers. Well, this laziness lead people down an incorrect logic path, one we now fight against virtually every day on these boards.

My point? My point is, you are leading people down another flawed logic path for the same reason, laziness (no offense). Saying "clipping doesn't kill speakers" is a half-truth at best. Technically no, clipping itself does not hurt the speaker. But in clipping your amp, you can easily create a situation that WILL kill the speaker. Was the squared waveform the DIRECT cause of the failure? No. Just like purchasing an undersized amp was not the DIRECT cause of failure. In the end, the answer is, always has been, and can only be... heat kills speakers. BUT, clipping increases heat generation, sometimes by a drastic amount. So to start a thread simply to state that clipping does not hurt speakers is, again, a half-truth at best.

I realize you have good intentions here. Do not take my comments as negative criticism of you or your intentions here, just adding my 3 cents to the discussion.

 

[Ed Lester 10+ year member]

I would like to see some proof that clipped amplifier signal will not blow a sub.

In SPL competition we actually like to run a slightly clipped signal. But this depends on the setup. I used to use a perfectly clean signal into the amps and then have a 5-10% clipped signal on the amp output to the subs. That was my old car with 8 MTX 1501Ds stapped to 2) 15" RFLs. and it like a full power Burp.

Clipping does not directly cause driver failure, its what you do with it.

Straight DC into a driver can blow it because of the heat created.

Amps can blow with clipped input signal and sometimes an amp can fail and cause straight DC to be sent to the driver. I have only seen this with cheap amps thou like Sony's

 

[Ed Lester 10+ year member]

If simply underpowering a driver could blow it, speakers would blow everytime you had volume set at any setting other than full.

 

[Slammed 5,000+ posts]

 

[BEAVER.989 10+ year member]

Light clipping is almost unavoidable under normal circumstances and likely will not cause harm to them speaker on the receiving end, I don't think anyone is arguing this fact... But to come out and say "Clipping doesn't kill speakers" is asking for trouble.

Drive any speaker into HEAVY clipping and you WILL have trouble on your hands, period.

Far too many subs capable of handling 1000W have been blown with amplifiers capable of producing much less for this to be untrue.

 

[IamDeMan 5,000+ posts]

I disagree. Clipping kills speakers.
How many times have you heard a noob say that they blew a sub because they underpowered it? An underpowered sub will not reach it's mechanical limits, but can reach it's thermal limit if pushed into by heavy clipping.

Yes ma sub can and does reach mechanical limits while being underpowerded. A coil is rated for 1000watts. They can't put a rating on the mechanical because it is enclosure dependent for the most part. My IB home sub has coils totaling 1500 watts of thermal ability, but my dayotn 1000 watt plate amp which probably conservatively puts out 800watts brings them all to their mechanical limits quite easily. Your response is flat out wrong.

 

[IamDeMan 5,000+ posts]

Sure, clipping occurs in nearly every electronic circuit. So does this mean if you are constantly taking small leaps, you can safely jump off that skyscraper as well? If you can jump up and down all day long with no ill effects, can you say jumping never killed anyone?
'Underpowering kills speakers' was a saying made popular years ago by people being lazy (myself included). Instead of explaining that people had a tendency to buy an undersized amp and then clip the hell out of it to get the output they desired from the speaker, we all just coined the phrase that undersized amps kill speakers. Well, this laziness lead people down an incorrect logic path, one we now fight against virtually every day on these boards.

My point? My point is, you are leading people down another flawed logic path for the same reason, laziness (no offense). Saying "clipping doesn't kill speakers" is a half-truth at best. Technically no, clipping itself does not hurt the speaker. But in clipping your amp, you can easily create a situation that WILL kill the speaker. Was the squared waveform the DIRECT cause of the failure? No. Just like purchasing an undersized amp was not the DIRECT cause of failure. In the end, the answer is, always has been, and can only be... heat kills speakers. BUT, clipping increases heat generation, sometimes by a drastic amount. So to start a thread simply to state that clipping does hurt speakers is, again, a half-truth at best.

I realize you have good intentions here. Do not take my comments as negative criticism of you or your intentions here, just adding my 3 cents to the discussion.

Thats what I am trying to say. It isn't the signal because a signal is just a signal, but in most circumstances clipped signal go hand in hand with the evils that kill our moofs.

 

[audioholic 5,000+ posts]

This discussion is ignoring mechanical limits. Like said above, it's extremely enclosure dependent and must be ignored. This thread is about thermal limits, nothing more.

 

[Ed Lester 10+ year member]

Light clipping is almost unavoidable under normal circumstances and likely will not cause harm to them speaker on the receiving end, I don't think anyone is arguing this fact... But to come out and say "Clipping doesn't kill speakers" is asking for trouble.
Drive any speaker into HEAVY clipping and you WILL have trouble on your hands, period.

Far too many subs capable of handling 1000W have been blown with amplifiers capable of producing much less for this to be untrue.

Especially if the heavy clipping can cause driver movement to become non-linear. Heat can build faster when the driver is not moving properly.

Ever hear people drive down the street with a factory stereo cranked to wear it sounds worse than dog doo? Why would they even want that much clipping. This has been one of my pet peeves my whole life.

 

[mokedaddy 5,000+ posts]

Clipping does not kill speakers technically speaking, heat does. Clipping will cause excessive heat however, which can/will lead to premature thermal failure.
Saying clipping doesn't kill speakers is like saying jumping off a skyscraper doesn't kill people, the sudden stop does. Technically true, but leads down an incorrect logic path. This thread will lead many people down that wrong logic path.

Thank you. I have been trying to say that but it seems nobody was listening. //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

 

[BEAVER.989 10+ year member]

Yes ma sub can and does reach mechanical limits while being underpowerded. A coil is rated for 1000watts. They can't put a rating on the mechanical because it is enclosure dependent for the most part. My IB home sub has coils totaling 1500 watts of thermal ability, but my dayotn 1000 watt plate amp which probably conservatively puts out 800watts brings them all to their mechanical limits quite easily. Your response is flat out wrong.

While everything you've said here is true, my response is far from wrong. Enclosure specifications weren't even brought into the equation here. I'm sure most of us are assuming the use of a correctly designed enclosure was a given.

 

[vehementSPL 10+ year member]

It just doesn't, and don't believe anyone who tells you it does. Seen 4 references to this shit in the last 30 minutes alone.

I am too lazy to read all these posts I gotta do something today. Anyways in case it hasn't be covered. It does but not directly . It raises the total power by maybe 10 to 20 percent (est. only). But why it blows speakers is because of the average power(the important stuff) is so much higher. Like say your amp puts out 1000 watts non clipped. Well due to the shape of the waves the average might be 30 percent of that power so you are getting a true 300 watts average that the coil has to dissipate. Now when you send a heavily clipped signal total power might go up to 1200 watts but the average now jumps up to 1000 watts because there aren't many peaks and dips of the music anymore. So now you literally have tripled the power to that coil. . And you are from indy. Same here what part of indy man?

 

[ultimate157 5,000+ posts]

Because said amplifier is no longer producing 1500 watts, it's likely producing much more than that. This is the reason why you have protection mode and clipping lights on amplifiers. As soon as the amplifier detects that you are over driving the amp, it either shuts down to protect the amplifier and the speaker because you're sending it more than rated power. There's no doubt in my mind that a solid 1500wrms amplifier is producing more than that anyway, plus when clipping fully is sending MUCH more than that. However, the same thing would happen if you send it 3000 watts from an unclipped amp. To a speaker, power is power, and whether that's via a clipped signal's 3000 watts or a unclipped signal's 3000 watts, it'll still reach thermal failure.

Just to elaborate on what PV is saying, let's add some math...

Say you are sending subwoofer A 1500w RMS @ 1 ohm with a clean sine wave. We'll say the frequency is equal to that of a fundamental sine wave.

Voltage = SQRT(W*R) = sqrt(1500 * 1) = sqrt(1500) = 38.72v

This is RMS wattage. Divide this by .707 and you get 54.76v peak voltage.

So now we have the peak and the period of the sine wave, so lets make it into an equation we can integrate.

Y = 54.76 sin(x)

Integrate this equation from 0 to Pi, and you will get the area under the curve.

54.76*-cos(pi) - 54.76*-cos(o)

54.76 + 54.76 = 109.52 units^2

Now for the easy part. A full square wave from 0 to pi is simply multiplying the length times the height. In this case, the length is Pi and the height is 54.76 (volts)

Pi * 54.76 = 172.03

Divide 172 by 109; This will give you the percentage increase in RMS wattage.

172/109 = 157%

Multiply by the original RMS wattage.

1500* 1.57 = 2355w

Although this is the extreme case of a fully clipped signal (Which isn't too hard to achieve anyway), it shows you that you can go from 1500w to a whopping 2355 by clipping.

Edit: After doing all this work I forgot I could've pulled the 54.76 out of the equation and simply integrated sin(x) from 0 to Pi and then multiplied after !