Originally Posted by Megasabin
How do you know if you "blow" something. Is it very noticeable?
Most definitely. With a blown tweeter you'll hear nothing in the upper register. Music will sound very very bloated.
With a blown woofer or midrange, pretty much the same thing - you won't hear anything in that range, or at least anything that will sound very good.
One way you can blow your speakers is by having an H/K. Well, almost. I have an AVR 520. Though the sound is wonderful, I'm grateful it's a high current. Approximately 4 times (last just on my new Energy RC-70's, but twice on my Polk RT800i and once on my Ascend 340's) I had the volume to max (about +8, not sure). Sound was distorted, I think, but not as bad as you'd think at full volume gain. The last two times iit occured was when I had my 100 watt/ channel PA2000 driving my mains.
Now I know what you're thinking, why on earth would I increase the volume to max. Answer is - I wouldn't. Far far too loud. Nice to know that no clipping occurs though as my speakers all held up fine. It was reported here once, but I have a faulty volume control. Very rarely, but once in a while, the volume just starts increasing like someone is holding down the volume gain button on the remote. It just does it. I've caught it a couple of times. But once I was painting when it happened, and the three other times I was doing some other kind of housework when it occurred. By the time I got to the receiver to turn it down, with my ears bleeding, she was already at max volume.
First thing I do is listen....well, first thing I do is let my ears recover. Next thing is put my ear up to each driver in my speaker to listent to make sure sound is coming out of it and it sounds OK (not like static, or pops, or no sound at all). Luckily I've never had my speakers blown. I believe it is because the h/k is a 'high current' amp it can get very loud and supply the current without clipping, at least in short bursts. As the sound was distorted at top level but no where near as bad as you'd think it would be.
So since my watas are far below my speaker rating, I agree that watts do not play as big a part as what people here say, but rather the current being drawn. Can it supply the current required for the watts at a certain volume level? If it can - even if you only have a 20 watt rated amp, like a tube amp, then you'll be fine if it can handle the current. A 300 watt amp / receiver means squat if the current can't provide the power being called for by the speakers at a certain volume level.
Speaker design also plays a lot into it IMO. Though I'd like to hear Paul's comments on that as being in the business he knows far far more than I ever will about that. But like amps (and receivers) you can buy 200 watt rated speakers for a ridiculously low price, but if you hooked those up to my receiver and it played one of it's tricks, I highly doubt a cheap speaker with badly designed crossovers would be able to handle it and would probably fry.