Wattage and power handling question?

Metaltastic

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Feb 20, 2005
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Alright, bear with me on this one, because while it may sound stupid, I just wanna be sure I understand it correctly.

Now then, my 2x12 cab with a pair of V30's can handle 120 watts (RMS I assume). However, what's really the deal with wattage, anyway? People have said that I can run a power amp with a higher output (say, 150 watts) than the cab can handle as long as I don't turn it up too loud, but wouldn't that mean that wattage = volume, when in reality, in kinda does but much more so means wattage = headroom?

Basically, I just don't get how if a 100 watt and a 200 watt amp are running at the same high volume into my 120-watt cab (but the 100 is distorting a bit more because of less headroom), the 200 is doing damage but the 100 isn't.

Clarification would be much appreciated, techies! (as well as a more practical answer than this theoretical hooha, which is whether I will be safe running a bridged mono 200-watt solid state power amp into my cab so I can have greater headroom than just running one of the channels at 100 watts)
 
Love to help you out, but... fuck that shit.

Basically, if it sounds like one of the speakers is going to implode, turn it off. Expressing an amp's power in watts is like trying to describe how blue a shirt is in terms of how long it takes to catch on fire when you microwave it. If the speaker can't handle the power going into it, it'll sound funny and pop... that's really about it. So don't pop them.

Jeff
 
Oh come on Jeff, you're god of all things tech around here, you can do better than that! Or maybe you're not as good as they say you are...maybe you're not my hero after all...

Now that I've busted out the reverse psychology card, I'm not surprised that wattage is a poor way to express an amp's power, but how (and why) do speaker companies determine the power handling in watts? Really, the active ingredient of my question is that I assume it's volume at certain levels that causes speakers to distort/rip, but if a 100-watt and a 200-watt amp can produce the same volume (just that the 100 might be distorting a bit more at the amp because of less headroom), is there any way the 200-watt would do more damage to the speakers than the 100-watt?
 
There's a very good reason why I don't give half a shit about amp power ratings beyond differences like 5W and 50W...

Put an old Marshall 50W up against a H&K 100W at full blast. If you survive, you won't think too much of such things anymore.

There's also a lot more to it than volume... putting the *wrong signal* through a speaker (playing bass through a guitar speaker and melting things, playing fuzzed bass through an amp with a tweeter and popping it) can kill something, mismatching impedances can kill lots of things... hell, different signals will stretch speaker limits differently. Take a compressed-as-80s-pants distorted sound and a fully clean and uncompressed sound with the same RMS loudness and you're going to have some very different peaks - and some very different risks to the speakers, as one is going to be constantly bouncing off the walls with hot, squished, distilled evil and the other is going to be stabbing its way out with its forehead because the thing is a mix of peaks and significantly quieter sustain.

Finally... ever put an 800W subwoofer in front of a 1200W amp? Recipe for disaster, right? Wrong-fucking-o... the amp very likely isn't using steady shots of hell to drive the sub so the woofer isn't necessarily going to die... but put a fuzzy bass tone into a bass cab with tweeters and you've got the steady square-wave-approximating noise whose effect on a speaker could best be described as getting chlamydia, going to take a piss, and then having every microbe inflate to the size of a Tic-Tac. Whoops.

Jeff
 
That's still short on technical shit, so I will be posting more later (I really should start studying this shit for the GRE, have yet to do any of that and I'm going to fucking need it), but for right now that's enough on why I tend to just go with 'turn it up until it sounds bad, and back off from there' with this sort of thing.

Jeff
 
Kickass dude, that's the Jeff I know! :headbang: It's less of an issue for now cuz I found out that while the ADA Microtube 100 watt poweramp is MosFET's, the Microtube 200 watt actually isn't...tricky sons of bitches.
 
Oh, and I definitely get your description, and it makes a lot of sense - I guess the dynamic range is why Celestion recommends a really bassy totally clean tone to break in speakers, rather than a totally compressed saturated one. Question about the bass thing, though - is "fuzz" achieved differently than just distortion? Cuz I would figure it'd be the same thing, between a compressed dirty tone being safer than a clean one with lotsa headroom (and therefore way more transients), but I take it by your tic-tac urine example that there's more to "fuzzing" then just overdrive...
 
Fuzz is usually referring to the saturation/buzz/messy shit that happens when a signal is distorted. I was just referring to distortion, yes. More or less distortion, or more or less graceful distortion (graceful distortion: SLO-100... not-so-graceful distortion: Fuzz Face...), EQ, and other such fun stuff will contribute to the 'fuzz', for example speakers (which are frightfully lo-fi, all things considered) or speaker simulators.

The thing with fuzz is that reproducing things that approximate square waves (more fuzzy tone gets closer to a square wave than less fuzzy tone) is a bitch and three quarters. It's entirely unnatural movement - speakers are used to going in and out, but with a square wave the motion is ININININININININIFUCKOUTOUTOUTOUTOUTBALLSGOBACKINININININININFUCKMENOWIT'SOUTOUTOUTOUTOUTGODSAVEUSALLOUTOUTOUT and that's just really not healthy for most things. Tweeters have the burden of a ton of the toppy hissy shit thrown on them, so instead of a nice, gentle reproduction of a 'natural' sinusoidal (fucking a girl gently and smoothly) we're jerking them back and forth and just asking for trouble (taking a jackhammer to an Asian nun in an earthquake, with donkey punches and wrecking bars thrown into the mix just for the hell of it) and, while the RMS for a square wave may not be very high, it doesn't take much to fuck things up.

Jeff