capacitor in series protect speakers from getting damaged due to signal clipping

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A sub will not get damaged by clipping, it's the tweeter that's in danger.
Clipping generates higher harmonics that can overdrive a tweeter because there is where the xover sends the higher freqs.
So to protect your tweeter from clipping, you need something that blocks the signal more with higher freqs. That's an inductor.

jan
 
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well why not ? The head of a square wave cannot go pass a capacitor. It will be blocked . wont it ?

Not sure this was addressed at me, but here goes:
The 'head' of the square wave is the low frequency signal itself. Woofers are carefully engineered to handle that ;)
The cap in series would only attenuate the signal you want to hear.
Its the spray of higher harmonics that is created by clipping that can damage your tweeter.

jan
 
Yeah. You can reduce treble frequencies by putting an inductor in series with the speaker. These are expensive. You can also put a small capacitor to ground (bypass) ahead of the low power parts of your power amp. This would be the input transistor or the input op amp. These are cheap and can be salvaged from old TV's or some other junk.
Peavey has a dynamic treble cut circuit in the input stages of their amps called the "DDT" , like the old PV-1.3K I'm working on . the schematic is on electronicservice.com. When too much high frequencies are detected, it squeezes the input signal to the supply rail (+16v) with a jfet. This cuts the input to the first op amp. There are a pair of PV-4 's with DDT for sale this week in my area for $150 ea. Probably need heat sink cleaning, input jack cleaning, re-e-capping and maybe a newer fan, but a good project to learn soldering on.
If you read Peavey's "white paper" on their website about speakers, he was paying for a lot of service replacements for speakers because of too much high frequency. So he asked somebody to invent the DDT.
 
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Yeah. You can reduce treble frequencies by putting an inductor in series with the speaker. These are expensive. You can also put a small capacitor to ground (bypass) ahead of the low power parts of your power amp. This would be the input transistor or the input op amp. These are cheap and can be salvaged from old TV's or some other junk.
Peavey has a dynamic treble cut circuit in the input stages of their amps called the "DDS" , like the old PV-1.3K I'm working on . the schematic is on electronicservice.com. When too much high frequencies are detected, it squeezes the input signal to the supply rail (+16v) with a jfet. This cuts the input to the first op amp.

Oh actually i do not have access to the tweeter's crossover circuitry. In fact its inside the speaker enclosure. However i can lower the treble frequencies through my graphic equalizer. Will this measure protect my tweeters ?
 
If the clipping happens before your graphic equalizer (like in a pedal or zener diode clipper or something). then, yes. If the clipping is happening in your power amp, you'll have to buy a "crossover" between the speaker and amp, which is expensive. Or build one out of high current inductors, which is also expensive.
Bottom line, learn to clip with a pedal or a tube preamp or tube head or something.
 
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The OP didn't mention anything about a tweeter, I'm very literal and since he mentioned "subwoofer" I'm assuming that's what he meant and that this sub-woofer either has an integral amplifier or an external power amplifier. I suspect he is probably talking about a typical home theater speaker package. Hopefully he will clarify what he means.

The OP has not mentioned whether this is a reflex, acoustic reflex, horn or bandpass. I suspect based on limited experience that clipping will be less obvious with a bandpass box than the other types.

The issues I can think of are running out of xmax if the woofer power handling and box design result in insufficient power handling under the specific clipping situation, and potentially overheating the VC.

A limiter and/or compression ahead of the power amplifier has been a traditional way of handling these issues, but of course just turning the volume down a few dB could be helpful as well.

Hopefully the OP will tell us a bit more about drivers, box(es) and amplifiers used, and whether the issue is mainly LFE related or more generalized.
 
Oh actually i do not have access to the tweeter's crossover circuitry. In fact its inside the speaker enclosure. However i can lower the treble frequencies through my graphic equalizer. Will this measure protect my tweeters ?

It will help but your music will be missing the high end. The above light fuse is what you need, but it has to match your tweeter (power).
 
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