Axiom Home Page Forums General Discussion Technical Questions 'square-wave proof' speakers?

Hi folks,

Are there any speaker technologies that don't get damaged by loud square waves?

Strange taste in music?

And my fiancee complains when I turn up Anti-Flag!

Bren R.

Are you talking about clipping?

Do you mean true square waves, in which the speaker driver must try to instantaneously move from max positive excursion to max negative excursion, or semi-rounded square waves, in which the attack is not so harsh?

Bren, hah

Basically extreme clipping, yes-- by your description, PM, it sounds like loud square waves would fry every speaker known to man?

Mike, it isn't entirely clear to me from what angle you're appoaching this. Although I rather like Bren's suggestion, I suppose that you're really thinking about clipping. A square wave of the same amplitude as a sine wave at the same frequency requires the square root of 2(i.e. 1.414)times as much voltage, and since power is proportional to the square of the voltage(i.e. P=V(squared)/R), this amounts to twice the power going into the speaker voice coil on a fully-clipped or square wave signal. Since the voice coil has to absorb twice the power, but it doesn't move any farther on the clipped or square wave to help it in cooling, it can overheat and fail if it can't dissipate the exta power over the time period involved. So, I suppose that answer is that no speaker is "square-wave proof", but the greater its power handling capacity, the greater its ability to play square waves at high level or to handle clipping without permanent damage.

John, that was very helpful. I had been of the thought that square waves damaged drivers through sort of 'jerking' them back-and-forth instead of a more normal sine-wave curve-- to hear it's a power / heat issue makes everything clear.

Thanks folks!

The power/heat issue and 'jerking' back-and-forth are closely linked.

At either flat end of a square wave, the driver is not moving yet a lot of power is flowing through the voice coil. The back-and-forth motion of a voice coil is what cools it, so the only chance the voice coil has to cool while reproducing a square wave is while it's in transit between the two extremes.

Since more time is spent "excurded" (the horizontal parts of the wave) than in transit (the vertical parts of the wave), this leads to rapid head buildup.

i believe these subs are designed to handle square waves http://www.globalsupersale.com/inc/pdetail?v=1&pid=3123

Obviously that's the case, Ron, but now even the sine waves will come out square.

Ah, didn't know that PM.

Makes me happy that Axioms have more than decent power handling.

Ok.. I'll bite.

Why on Earth would you want to listen to square waves?
(For some reason or another, I have a feeling the answer will be "to listen to my Wierd Al Yankovic album".)

And if you don't want to listen to them, why else would it be necessary to run them through your speakers?

hehe..
I listen to square waves all the time when im playing with my synth..It's kindof cool listening to square, sawtooth, triangular and sine wave thru high performance speakers..
If your a tweaking around with an analog synth the sound your making with begin with a basic wave like above and then youll start to fool around with the attack, delay , sustain , release and all that other fun stuff.

Reminds me of this keyboard my family had when I was in junior high.

Oh... That makes sense. Thank you stbean.

Hah pmbuko!! I still have that bad boy! Its a great little synth.

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Are there any speaker technologies that don't get damaged by loud square waves?

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One thing you could do if you WERE looking to protect your speakers is find the Speaker Z (in ohms - 8 for most Axioms) and the Peak Power (or 4x Continuous Average Power is a good base) and cross reference them on a fuse nomograph, and put a slo-blo fuse in serial to protect them from thermal damage (or a fast-blo instrument fuse to protect tweeters from large transient voltages).

(ie: 8 ohm, 75W Peak = 1.5A)

If anyone's that interested, I can bring home and scan the nomograph.

Bren R.

Your welcome....pardon my horrible grammar in that reply. I probably didnt have my coffee yet!

Bren, I'm not far enough into applied electronics to set that up, but I enjoyed the information regardless.

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Bren, I'm not far enough into applied electronics to set that up, but I enjoyed the information regardless.

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My math stinks... so anything past basic + - x /, I like to have a chart.

Find two points, draw a straight line through the answer.

Bren R.