Damaging speakers with square waves?

[Electricblue]

Hey guys, I need to settle something in a heated debate with a friend. This page will be shown as proof...

Is it square-waves that kill speakers? Or does it make it easier to kill speakers because it masks speaker distortion?

I'm a regular user of heavy overdrive, and according to my friend I'm killing my speakers

[Mr. Foxen]

It is BS. Is your friend a guitarist? They like to say stuff like this, and it doesn't occur to them about the amp clipping they routinely feed to their amps when they engage the drive channel.

There are a few aspects of truth to it though. One is that a clipping amp can output more than its rated power, which means you can melt speakers with a lower rated amp (although it will sound terrible first, and they'll have farted and creased before melting). The other is that a crossover can't shunt disproportional amounts of power to high frequency drivers if fed by a clipping amp, tweeters sound terrible with drive anyway, so not really an issue. The only risk from pedals creating the distortion is that the distortion sound you expect is covering up the sound of the speakers/amp distorting and you don't think to turn down. Big Muff is a classic for this as they have a mid scoop tone knob, which makes them seem quieter, whilst outputting loads of fuzz and bottom, so can be wrecking your speakers whilst not seeming that loud.

[JimmyM]

If square waves killed speakers, then you couldn't amplify synths or distorted guitar. Total crap and nonsense. I've used distortion on bass for decades. Total amount of speakers I lost to it: 0.

[alexclaber]

Myth.

http://barefacedbass.com/uploads/BGM67%20Jun2011.pdf

[JxBass]

It's why I always play in Sine waves

[sad_katz]

Nope.

What *does* kill speakers is feeding more power than the cone's *physical excursion* limits. Either from too much volume, EQ boost (usually from boosting bass to kingdom come), power amp clipping thus sending extra power, or combination of both. Physical excursion limits information on commercial cabs are often buried away in the user's manual, if any. Speakers usually blow themselves before the voice magnets begin to melt, which incidentally triggered the next myth: underpowering :/

Just keep in mind the sound that's coming out of the cab and you'll be fine. If the sound is farting (there's no pedals that simulate fart sounds yet, right? ) or if you can see the cones moving really far, back off the volume/EQ boosts.

[walterw]

Originally Posted by JxBass

It's why I always play in Sine waves

yep, me too.

wait, according to that fourier guy, we all do

+more to the square wave thing being a myth.

a power amp being pushed into square wave clipping is putting our way more power than it's supposed to, up to twice as much. if that power is too much for too long, it cooks the speaker.

on top of that, the clipped amp is also compressed, so that if it's too much for the speaker, it's also too much constantly, with no chance for the speaker to cool back down.

[billfitzmaurice]

Originally Posted by Electricblue

Hey guys, I need to settle something in a heated debate with a friend. This page will be shown as proof...

Is it square-waves that kill speakers?

Woofers never see true square waves. What makes a square wave square is very high harmonic content. The high inductance of woofer voice coils filters out most of those harmonics. What they don't filter out still doesn't add enough power to the signal to bother them.

[Mr. Foxen]

Originally Posted by sad_katz

If the sound is farting (there's no pedals that simulate fart sounds yet, right?

Nasty farting noises can be coaxed out of loads of pedals if you try.

[spode master]

Isn't the real issue with Hard Clipping an amplifier. Some handle it more gracefully than others, and some can stick to the rails. I have Dislodged the coil of a 2245 from its gap before, bad times.

[billfitzmaurice]

Originally Posted by spode master

I have Dislodged the coil of a 2245 from its gap before, bad times.

Not as the result of clipping, only as the result of overpowering.

[madmatt]

It depends on the frequency too.
If you were driving your speaker at it's max power handling with a 1Hz square wave I would say the chances of it being damaged are pretty good. But if it is being driven by square waves in the 40Hz to 5KHz range probably not as easy if at all.

[DrSmaggs]

I've been playing with thick overdrive from my sansamp RBI since 2002. ALL of my speakers in my 8x10 are still working perfectly. Butter Zone!!!

[spode master]

Originally Posted by billfitzmaurice

Not as the result of clipping, only as the result of overpowering.

Or at least a transient peak that exceed the Xmech?

[Mr. Foxen]

Originally Posted by spode master

Or at least a transient peak that exceed the Xmech?

That is too much power.

[s_mcsleazy]

its nonsence. the only way to kill a driver like that is if you used square waves with like 300 watts more than the recomended amount

[spode master]

Originally Posted by Mr. Foxen

That is too much power.

Ohh in a ported cab its perfectly possible to exceed xmech while staying within power handling. Just means your operating bellow port tuning, out of intended range of opperation XD.

I suppose it could be to much power for that pass band :|

[onosson]

From my experience, you're far more likely to damage speakers from a very clean uncompressed signal than you are from one that is distorted (and therefore at least somewhat compressed), at similar (high) volumes.

[seamonkey]

Record yourself playing heavily distorted then look at the waveform in any DAW.
Just play one note.
It's not going to be a square wave.

Run the track through some spectrum analysis.
Undistorted first.
Distorted second.

The Distorted is not going to have a stronger fundamental.

[billfitzmaurice]

Originally Posted by seamonkey

The Distorted is not going to have a stronger fundamental.

Of course not. Those who think that square waves are problematic have no understanding of what square waves are.