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

[ultimate157 5,000+ posts]

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?

Read my above post. Sending a square wave will increase the power to a maximum of 57% higher.

 

[audioholic 5,000+ posts]

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.

So if one sub's "correct box" is a large ported box tuned low, while another sub's "correct box" is a tiny sealed one.... how do you plan to give any realistic comparison between the two in terms of mechanical limits versus input power?

 

[Ed Lester 10+ year member]

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 !

while this is a good example of how much power an amp can put out over its rated power when clipping, you have to note that this is in a near perfect world. Realistically amp efficiencies and power supply and amp heat and driver impedance rise will lower this number

 

[ultimate157 5,000+ posts]

while this is a good example of how much power an amp can put out over its rated power when clipping, you have to note that this is in a near perfect world. Realistically amp efficiencies and power supply and amp heat and driver impedance rise will lower this number

Yes there will be some decrease, but the ratio will still be the same. 57% from a sinusoidal wave to a square wave, no matter the wattage.

That's still a huge jump.

 

[BEAVER.989 10+ year member]

So if one sub's "correct box" is a large ported box tuned low, while another sub's "correct box" is a tiny sealed one.... how do you plan to give any realistic comparison between the two in terms of mechanical limits versus input power?

I'm assuming we are talking about one constant sub in one constant enclosure, said enclosure is correctly designed to provide a q of .707

... we apply power from a nonclipped amplifier that is capable of producing the RMS power that the sub is thermally capable of taking... we then remove this amplifier and add a considerablly lower powered unit and crank the gain until we see the same output voltage of the original unit. We are now heavily clipping.

Which sub do you think is going to fair better? The one seeing power equal to that of it's RMS rating, or the one that is underpowered but heavily clipped?

I don't know why I even typed all of that. You know the answer... I think you're just testing me. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[ultimate157 5,000+ posts]

I'm assuming we are talking about one constant sub in one constant enclosure, said enclosure is correctly designed to provide a q of .707
... we apply power from a nonclipped amplifier that is capable of producing the RMS power that the sub is thermally capable of taking... we then remove this amplifier and add a considerablly lower powered unit and crank the gain until we see the same output voltage of the original unit. We are now heavily clipping.

Which sub do you think is going to fair better? The one seeing power equal to that of it's RMS rating, or the one that is underpowered but heavily clipped?

I don't know why I even typed all of that. You know the answer... I think you're just testing me. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

The one with the clipped signal, of course.

clipped signal does not hurt the driver mechanically, unless you are reaching its mechanical limits.

 

[BEAVER.989 10+ year member]

The one with the clipped signal, of course.
clipped signal does not hurt the driver mechanically, unless you are reaching its mechanical limits.

Are you serious? You'd rather have an underpowered clipped signal than a clean high powered signal? You must have misunderstood me somewhere along the line.

If that's the case, why don't you sell your 2000D and but a 1000D and turn up the gain until you've reached the desired output voltage?

 

[ultimate157 5,000+ posts]

Are you serious? You'd rather have an underpowered clipped signal than a clean high powered signal? You must have misunderstood me somewhere along the line.
If that's the case, why don't you sell your 2000D and but a 1000D and turn up the gain until you've reached the desired output voltage?

There is a huge difference between your two posts.

The first one, that I quoted, said which is going to fair better. This means physically.

Now you're saying which one would I rather listen to. Which one is it?

 

[BEAVER.989 10+ year member]

There is a huge difference between your two posts.
The first one, that I quoted, said which is going to fair better. This means physically.

Now you're saying which one would I rather listen to. Which one is it?

I think we have both misunderstood eachother a little... but to answer your question... both.

The sub receiving the clean signal should both last longer and sound better, IMO.

 

[newusername 10+ year member]

I'm getting tired of this argument, too. For example, the following sentence doesn't even make sense:

The one seeing power equal to that of it's RMS rating, or the one that is underpowered but heavily clipped?

Part of the problem is that people only imagine power as what they read on the amplifier box....they don't understand the fundamentals.

This topic has been discussed to death here and a search will reveal your answer. Other sites have discussed/are discussing it, too.

People need to understand that clipping only increases the average power over time. Nothing magical about it.

 

[Ed Lester 10+ year member]

nothing beats high clean power

 

[BEAVER.989 10+ year member]

I'm getting tired of this argument, too. For example, the following sentence doesn't even make sense:

Quote:

Originally Posted by Beaver

The one seeing power equal to that of it's RMS rating, or the one that is underpowered but heavily clipped?

Part of the problem is that people only imagine power as what they read on the amplifier box....they don't understand the fundamentals.

This topic has been discussed to death here and a search will reveal your answer. Other sites have discussed/are discussing it, too.

People need to understand that clipping only increases the average power over time. Nothing magical about it.

Hey, I'm all for learning new things, that's why I'm here, but I do have a question...

If mild clipping is inaudible and even heavy clipping won't damage your speakers, than why is "headroom" all the rage? If clippings not harmful, shouldn't we all just buy smaller amps and clip 'em a little?

 

[ultimate157 5,000+ posts]

Headroom is the rage for future upgrades, mostly.

I wouldn't buy a 600w amp to power a single 600w sub, because I don't know what I'll want in the future.

Perfect example: I bought my 2000D to power an eclipse SW8200 (SVC 4 ohm) I am now going to wire it down to 0.5 on 2 mags.

 

[BEAVER.989 10+ year member]

Headroom is the rage for future upgrades, mostly.
I wouldn't buy a 600w amp to power a single 600w sub, because I don't know what I'll want in the future.

Makes sense if that's the only reason for it. It seems everybody is after headroom even if they never plan to upgrade, though... IDK.

 

[IgnoreMe 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.

how is it not producing 1500w if i clamped it and saw it for myself? this happened with my btl and kx2500.1.

i burped my sub before and calmped it. the highest ive ever gotten was 1600w @ 3.9 ohms out of that amp. 3.9 was my lowest impedance of all the freq. i played it on music and have gotten the btl to stink up before.

i just dont get it, considering music is dynamic and it probably did even less power than that on most songs. im not saying you dont know what you're talking about so dont take offense, im just saying its not making sense to me.