Clipping (what It Is)

[IH8PunkRok]

due to my own irratation of people not knowing ive decided to inform as best i can

What is clipping?

Clipping is a form of waveform distortion usually caused by overdriving an amplifier.

some things about clipping and its effect on subwoofers.

-clipping is not something u should worry about if u know what ur doing

-clipping causes distortion which by the human ear sounds "louder"

-clipping creates more power but it is dirty and u dont want it

-clipping creates more heat from the amp and sub

-dirty signals can come from music, the headunit or the gains of the amplifier

-underpowering is not clipping and will not harm your sub

-if u have an amp that doesnt have enough power for your sub but u want it to sound louder and u turn the gains up real high (between 65% and 100%). that will cause clipping and kill your sub

-clipping wont destroy a sub immediately. the amount of time it takes for a sub to die is depndant upon the average listening volume of the user

here is a visual example of clipping

both are 40 hz tones

the bottom one is at 0 db recording level

and the top one is at +5 db recording level

(the decibel level of a recording determines the dynamics of the music. the decibel level written on a cd determines the amount of voltage coming from the HU to the amplifier. more voltage = louder. so at 0 db recording level the max voltage is being sent out at the specified volume level your HU is set to.)

these are visualizations of the instructions the amplifier recieves. when it gets these plans it creates the power and sends it out to the subwoofer.

now as u can see the top one is missing parts of the wave on top and bottom compared to the non clipped wave.

think of these waves as the way your sub moves. the wave goes up the sub pushes out, the way goes down the sub sucks in. so naturally u want a very smooth transition so that the sound is smooth.

but when u have a clipped signal (like my example) the sub is forced to stay at its peak for .3 ms longer than it normally does. so when the amplifier gets these instructions it knows that the subs has to stay at the top of the wave for .3 ms longer than before. the only way it knows how to d o this is to create more power. so it makes more power and pushes the sub harder to keep it up there longer.

when this happens more power is going to the voice coils (which makes them hotter) but the sub is not moving more than with an unclipped signal. so it is creating more heat with the same amount of cooling. that is wut causes drivers to burn up.

so it is smarter to buy and amplifier that has more power than u need and keep the gains low to prevent clipping.

if anyone has anything to add about clipping then please do

[aznboi3644]

www.bcae1.com is very helpful for noobs to learn something

[aquill1]

My question is how do you honestly tell clipping to the naked ear? I've always wondered perhaps I may never find out...only sub I've ever blown was one that was garbage in the first place...

[IH8PunkRok]

clipping is very hard to hear by ear

the only way i can think of is have 2 systems side by side same everything have one clipping and the other not

im thinkin it should sound fairly sloppy in high volumes

[MickyMcD]

Overdriving a Class A/B, A, B, D, or H power amplifier also results in an increase in output power and induces DC current across the coil (class TD, as used by Lab.Gruppen, and valve amplfiiers behave differently). DC Current is a speaker serial killer, and should be avoided.

Overdriven amplifiers are very easy to hear if they are powering hi, hi/mid, mid or low/mid loudspeakers. However, overdriving low end amplifiers' results in almost inaudiable distortion unless it is harshly overdriven. Clipping a waveform induces Harmonic Distortion. Overdriving a 10k sine wave will result in the next harmonic overdriving at 20k, which is extremely hard to hear with human hearing. However, overdriven waveforms at a lower frequencies induce harmonics that are quite audible.

A good document writen by Peavey outlines the basics of clipping, however it focus' mainly on pre-amplifier stage distortion. Never the less, this document is extremely healpful and informative.

http://www.peavey.com/support/technotes/co...ngrevisited.cfm

Cheers,

Mick

[aznboi3644]

It is easy to hear clipping if you are playing a sine wave.

[IH8PunkRok]

Overdriving a Class A/B, A, B, D, or H power amplifier also results in an increase in output power and induces DC current across the coil (class TD, as used by Lab.Gruppen, and valve amplfiiers behave differently). DC Current is a speaker serial killer, and should be avoided.

Overdriven amplifiers are very easy to hear if they are powering hi, hi/mid, mid or low/mid loudspeakers. However, overdriving low end amplifiers' results in almost inaudiable distortion unless it is harshly overdriven. Clipping a waveform induces Harmonic Distortion. Overdriving a 10k sine wave will result in the next harmonic overdriving at 20k, which is extremely hard to hear with human hearing. However, overdriven waveforms at a lower frequencies induce harmonics that are quite audible.

A good document writen by Peavey outlines the basics of clipping, however it focus' mainly on pre-amplifier stage distortion. Never the less, this document is extremely healpful and informative.

http://www.peavey.com/support/technotes/co...ngrevisited.cfm

Cheers,

Mick

u really know wut ur talkin about dont u?

[aquill1]

How else can you test for it than? Are the clipping meters accurate say on the rockford fosgate power 1000 25 to life?

[Guest MegaloManiac]

clipping itself wont kill your sub overpowering your sub will kill it

here is a 45hz severly clipped track http://media.putfile.com/45hz-clpped. wont do anything to your equipment unless you overpower

Edited February 20, 2008 by MegaloManiac

[MickyMcD]

u really know wut ur talkin about dont u?

I am not too sure if that was sarcastic, but I think it wasn't. Thank-you. I have spent many years now learning and being taught by sound technicians across Australia. Unfortunately, as it goes with all work, if I didn't know my stuff I'd quickly find my ass out on the sidewalk and looking for another job.

clipping itself wont kill your sub overpowering your sub will kill it

here is a 45hz severly clipped track http://media.putfile.com/45hz-clpped. wont do anything to your equipment unless you overpower

Cha-ching, he's in the money. Pre-amplifier stage distortion will not harm your loudspeakers. Also, thank-you Megalo for going that one step further and conducting experiments and displaying the evidence to the forum. No-one can argue with the proof you delivered.

Cheers,

Mick