Hello. I've seen quite a few posts on other forums and facebook groups where people are claiming that under powering a speaker is very dangerous and can damage the speaker more than overpowering it. The explanation is added that under powering leads to clipping the amp and that will create a square wave that basically destroys the speaker. Something doesn't sound right to me, so I came here to ask the experts. Is this true? What's the whole story? What really destroys the speaker? I've personally under powered speakers before and haven't experienced any problems, but I've also kept things out of the red.
Clarify the point
- Thread starter Carlos Doyle
- Start date
Hi Carlos,
Underpowering a speaker is not dangerous at all so long as you avoid excessive clipping. Different amplifiers have varying degrees of how well they handle clipping. This was more of an issue with older amps that had no internal DSP, in which case you needed to use your ears (hear the distortion) or see with your eyes (via the limit light). Modern amps with DSP typically have limiters which you can set which will significantly reduce the risk even further.
The short version of this is: don't abuse your system and you'll be just fine underpowered.
My main reason for wanting to provide lots of power has nothing to do with speaker damage, it has to do with having the headroom to cleanly reproduce transient peaks. This can be a factor in the perceived sound quality in live band mixes. It's less of a factor for DJ and track playback purposes, as that content is highly compressed.
Underpowering a speaker is not dangerous at all so long as you avoid excessive clipping. Different amplifiers have varying degrees of how well they handle clipping. This was more of an issue with older amps that had no internal DSP, in which case you needed to use your ears (hear the distortion) or see with your eyes (via the limit light). Modern amps with DSP typically have limiters which you can set which will significantly reduce the risk even further.
The short version of this is: don't abuse your system and you'll be just fine underpowered.
My main reason for wanting to provide lots of power has nothing to do with speaker damage, it has to do with having the headroom to cleanly reproduce transient peaks. This can be a factor in the perceived sound quality in live band mixes. It's less of a factor for DJ and track playback purposes, as that content is highly compressed.
Clipping causes more heat in the voice coil and heat is the long-term enemy of both transducers and electronic components. A clipped waveform has more output which must be dissipated.
It's not a form of instantaneous failure, but over time is detrimental. That said, I tended to power-limit subwoofer signals to 1/4 (or less) of the maximum input rating for long term operation. No clipping at the amp output but the same might not have been the case for INPUT signal sent to the amps.
It's not a form of instantaneous failure, but over time is detrimental. That said, I tended to power-limit subwoofer signals to 1/4 (or less) of the maximum input rating for long term operation. No clipping at the amp output but the same might not have been the case for INPUT signal sent to the amps.
Totally agree with the responses, and sadly have seen it happen far too many time. Even worse is that because sub bass content doesn't sound like ‘music’ seeing an amp running attenuators mid way is to some people, evidence it could go louder, so they turn up, and hear no real change, so turn up more. Then speakers die. In my theatre after losing numerous subs, i realised visiting shows were not hearing enough low bass, spotting our amps in the rack and while we were not looking, would turn them up, and down again after the show. We then found next show one of the subs was dead. We even worked out which show it was when the same thing happened next time. Too late, of course, but the amp rack grew a locked door!
Loudspeaker drivers are damaged from being overpowered in some way, too much peak power(causes over excursion) or too much continuous average power(causes VC overheating), the catch is that it is possible to achieve either of these with any size of amplifier it just depends on the specifics of the situation. Clipping a signal in itself is of no real danger, but when an amp is driven into clipping the average signal level increases and most of the extra energy is at higher frequencies and that could lead to the HF driver being overpowered. LF drivers are less susceptable to amp clipping, the inductance of the voice coil acts as a low pass filter so all that extra clipping energy doesn't amount to much of a power increase for these drivers. So yes an undersized amp can be dangerous if the operator doesn't care what the system sounds like, but a more powerful amp is even more dangerous in the same hands.
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