Well - my speakers caught fire.

[RustyNails]

On the pedal may have caused it theory: can electricity powerful enough to start a fire even travel through a 1/4 inch instrument cable? I'm no electrician but seems unlikely if not impossible. The only way I could see the pedal even having any contribution to such destruction is if the power supplies of the board and the amp itself were on the same circuit and even then it's sketchy at best.

 

[ole Jason]

I got a hearty chuckle out of the people who think a distortion pedal can cause speakers to spontaneously combust. All those guitar players are playing with fire on a nightly basis every time they step on their trusted TS.

 

[RoadRanger]

Any audio engineer who says a distortion pedal will cause a fire is not someone who's professional opinion I trust.

If you're running an amp rated at 400wrms sinewave output at 4 ohms into a 400wrms rated 4 ohm cab the pedal can push the output as high as 800wrms of squarewave output. A 400wrms sinewave has the same peak voltage as a 800wrms squarewave. If you're running any overdrive or distortion you should run your cabs off an amp rated at 1/2 the cabs' rating and then you'll be OK.

 

[DirtyDuke]

If you're running an amp rated at 400wrms sinewave output at 4 ohms into a 400wrms rated 4 ohm cab the pedal can push the output as high as 800wrms of squarewave output. A 400wrms sinewave has the same peak voltage as a 800wrms squarewave. If you're running any overdrive or distortion you should run your cabs off an amp rated at 1/2 the cabs' rating and then you'll be OK.

Seriously?? Are u saying if you run a distortion pedal and a 500 watt amp u need a 1000 watt cab?

 

[DirtyDuke]

If this is true then I should have burned down venues from one, end of Canada to the other

 

[moody]

I have had a speaker smoke at a gig once (a long long time ago). All the transistors failed in the amp and it was producing DC to the speaker. This was due to trying to get too much power from said amp and speaker and it overheating. I was stupid and plugged the amp into another speaker at home - two down.

 

[B-string]

C. For musical instrument application, where
distorted (overdriven) output may be a musical
requirement, the system should be powered with an
amplifier capable of delivering only one-half of the IEC
rating for the system.
Discussion: Much rock music is produced at full
output with the amplifier well into clipping, and this is a
matter of musical choice. When an amplifier capable of,
say, 300 watts of undistorted sinewave output is driven
well into clipping, its output power can approach 600
watts! So, Berating the system to one-half its IEC power
will result in safe operation of the loudspeaker.

That is JBL's position, if you know better than they do you are wasting your time here

 

[RoadRanger]

Seriously?? Are u saying if you run a distortion pedal and a 500 watt amp u need a 1000 watt cab?

Yep - assuming you might turn it all the way up. But as I always say, it's your stuff so smoke 'em if yah got 'em . We always appreciate a good laugh here ...

 

[DirtyDuke]

Yep - assuming you might turn it all the way up. But as I always say, it's your stuff so smoke 'em if yah got 'em . We always appreciate a good laugh here ...

The pedal or the amp?

 

[DirtyDuke]

The pedal or the amp?

Nevermind. Don't answer. One ridiculous answer after another doesn't change anything. Theoretical BS, that stretches the boundaries of common sense of real life data doesn't make it so

A DISTORTION PEDAL CANNOT. START A FIRE.

Have a good night guys. It's been fun.

 

[blindrabbit]

C. For musical instrument application, where
distorted (overdriven) output may be a musical
requirement, the system should be powered with an
amplifier capable of delivering only one-half of the IEC
rating for the system.
Discussion: Much rock music is produced at full
output with the amplifier well into clipping, and this is a
matter of musical choice. When an amplifier capable of,
say, 300 watts of undistorted sinewave output is driven
well into clipping, its output power can approach 600
watts! So, Berating the system to one-half its IEC power
will result in safe operation of the loudspeaker.

That is JBL's position, if you know better than they do you are wasting your time here

Power amp clipping is what I believe they are speaking of. Pedals don't make power amps clip. Even a clipping preamp doesn't necessarily make a power amp clip, or a pedal running into a clipping preamp either. PA speakers play "much rock music" all the time, and even at loud volumes, but my guess is that the PA's power amp isn't being run at clipping, otherwise nightclubs and other venues around the world would have speakers bursting into flames all the time, no?

It may also be worth noting that the quoted paper appears to be from 1990. Sure, physics is rather constant over time but it wouldn't hurt to see a more current authority on the subject.

 

[RoadRanger]

The pedal or the amp?

Both

 

[DirtyDuke]

Both

See. Theoretical nonsense. Who runs an amp and pedals flat out? No one that's who

 

[BurningSkies]

Both

A pedal sitting on the floor by itself doesn't do much of anything, does it? I don't know why people are confused by the concept that all parts of the signal chain can cause failure to speakers once they make it through a device that amplifies what they're doing. I don't believe that people are saying that clipping in general causes problems either...obviously given that most of the people here frequently point out that distortion doesn't necessarily in itself (nor does wave shape) cause damage.

 

[RoadRanger]

PA speakers play "much rock music" all the time, and even at loud volumes, but my guess is that the PA's power amp isn't being run at clipping, otherwise nightclubs and other venues around the world would have speakers bursting into flames all the time, no?

Actually back in the day it wasn't unusual to run the sub amp(s) into clipping as a 800w amp was BIG back then, capable of
pushing well over 300w into each of four 8 ohm drivers. Drivers capable of those power levels were just starting to come out. Reggae in particular was diggin' the square waves bass sound .

 

[Matt O]

?...I'm going to run all 16 of my fuzz pedals, 9 distortions, 6 overdrives and 2 compressors at max settings for 30 minutes and see what happens.

I have nothing to add to this conversation other than this is probably the best potential sig quote I think I've ever seen.

Ahem, carry on...

 

[DirtyDuke]

I have nothing to add to this conversation other than this is probably the best potential sig quote I think I've ever seen.

Ahem, carry on...

Awesome. This is why I love talkbass. I'll let u know how it goes.

Look for next week's feedback friday!!!!

 

[pravus]

Power amp clipping is what I believe they are speaking of.

Not quite. What is being talked of is a compressed signal chain having a higher RMS leading to a thermal failure in a speaker. While the example of a distortion pedal is used, this doesn't have to be the case so no clipping is required.

 

[B-string]

I personally don't find childish or ridiculous ramblings sig worthy. Different strokes .

 

[Gizmot]

You didn't smoke the drivers with power - you did it with distortion. When amplifiers run out of headroom, it stops being able to control the movement of the cones. This causes the amp To put out square waves that cause the cones to go inward and outward as far as they can. This causes the voice coils to heat up much more than normal. Get your drivers repaired or replaced and get a seriously more powerful amp. You don't blow speakers with power , you blow speakers with distortion