I've read on this message board and in other forums that when a speaker is underdriven, you'll get distortion. That's to be expected, I suppose, but I'm curious about how much power is actually required.
Take an example component system rated at 80W RMS (for example, the BA SL60). Does one really need to drive these speakers at 60-80W to avoid the underdriven distortion that so many folks refer to?
Continuing with the BA SL60 example, these guys are rated at 90db @ 1m @ 2.83V so basically 90db @ 2W input. At, say 64W input, I figure the SPL would be around 105db @ 1m (5 power doublings @ 3db per doubling). A pair of these guys running at 64W would yield upwards of 108db @ 1m.
I haven't used a sound meter to measure my typical listening volume but I'm sure it's below 108db. I would guess somewhere in the 85-90db range. Does this mean that if I were to install a pair of 80W RMS components (like the aforementioned SL60s) that I would be underdriving these speakerss and thus be better off using something else?
Apologies if this is a naive question but there is a method to the madness. For my install (I'll make a second thread later with details seeking commends/recommendations), the amp will need to fit under the seat. If I were to go with a 4ch amp to power fronts and rears, I'm probably going to be limited to something like 60x4.
if you use your volume control responsibly and set your gains correctly, you won't be clipping the signal and sending distortion through your speakers, regardless of how far under the speakers rated RMS your amplifier is rated at.
Thanks, guys. That's what I was scratching my head about. I was aware that severe clipping could cause damage and distortion but it didn't make sense how simply playing at a low volume could cause damage unless the speaker is designed such that it absolutely needs the cone to travel the full excursion distance in order to cool the voice coil (surely that would be considered a design flaw and would never make it to market).
its not that clipping causes distortion, clipping is distortion, just like the waveform of a distorted electric guitar. Music is filled with clipped signals and it won't damage your speakers until you crank up the volume to a level where the speaker can no longer dissipate heat created by current flowing through its coils. The trick is that clipped signals cause the speaker assembly to move in a way that cuases heat be dissipated less effectively. People fear damage due to clipping their amplifiers because if they matched up the rated output with the speakers rated handling, if you're driving the amp to a level where its clipping the singal, its putting out more power than its rated output, which may very well blow the speaker.