Speaker Power Handling vs Amplifier Power - Audio Myths

Andrew discusses the power handling of a loudspeaker vs amplifier power - the reason why this is a myth, standardization issues, what to do if you hear a 'thump', and what to do really quickly if you smell something coming out of your speaker suddenly.

Speaker Power Handling vs Amplifier Power - Audio Myths

Today in our ongoing series of audio myths and trying to dispel them, we're going to talk about something that confuses people greatly, and that is power handling of a loudspeaker versus amplifier power. Now, this came out of some comments to a previous video I did on are my speakers blown and how to tell. There is this common misconception that people have that if they have a speaker that's, let's say, rated to handle 200 watts and their amplifier is only 100 watts, that there's no way that they can actually damage their speaker because if the speaker can handle 200 watts and the amp's only a hundred, well, I'm fine. I'm below the power.

Well, unfortunately, it doesn't work like that. There are many different things at play. One problem is that there isn't really standardization that most manufacturers use on how they rate power handling of a loudspeaker. There are actually international standards that tell you how you should measure and how you should specify the power handling of a loudspeaker, but many manufacturers just throw a number out there. Unless they've specified they're following a particular standard, who knows how they come up with that number?

One thing that's very important to realize is that even if you follow a standard for power rating of a speaker, usually, the test signal that's used is wideband and it's fairly continuous. What I mean by that is that it handles pretty evenly a wide range of frequencies that the speaker might cover. Sometimes it's what's called "pink noise" or "white noise" or some modifications of those things. But often, those power tests don't include the kind of dynamics and the kind of frequency response bumps that you might encounter in music or in sound effects in movies.

Let's say, for instance, that you put on a track that's got a real heavy, really low thumping bass note. Well, you can easily, even with only that hundred-watt amplifier, overdrive the woofer in a speaker that has a power rating of 200 watts because those peaks of every one of those heavy thumping bass beats might be either clipping the amplifier so you're overdriving the amp and producing a bunch of distortion and other nasty things into the loudspeaker and actually dumping more power than the actual rating of the amplifier seems to be into the speaker, or if it's a really good amplifier, it may have dynamic power capability that is way above a hundred watts, might be 200, 300, 400 watts for a short amount of time when those bass thumps are happening in the music.

Just because you're following some numbers, specifications will lie to you. This is a perfect case. You cannot simply go, "Well, I can't possibly have damaged my new speakers because the volume control was only at 75% and my amplifier's only half or three-quarters of the power handling of the speaker, so nothing can be wrong with them." Unfortunately, when that person goes on to the forums to say, "Why is my speaker sounding funny?" people may or may not tell him, "Hey, guess what? You may have damaged your speakers," so don't follow those rules.

Now, what should you follow? This is just really a common sense thing. If you hear your speakers making any sort of strange noises, like every one of those bass thumps, there's a little click or a tick or a crack sound or something like that, sounds like something mechanical is going on that doesn't seem to be part of the music, turn the volume control down. You are probably going to damage your speakers if you keep that up.

Another thing which coincides with amplifier clipping is the speaker, is the music starting to sound really harsh, really shrill, something, it really hurts your ears? Often, that means you've hit the limits of something, whether your amplifier or your speaker, and it's telling you to turn it down. That's one thing that you can really, really use and it's really, the only thing is use your ears and use your common sense.

Now, there is one other thing. If you really massively overdrive your pair of speakers, you may actually start to smell something. When voice coils heat up, typically, the resin that's used to bond the magnet wire that makes up the voice coils, there's a distinct electrical smell. It's not really a burning smell, but it's like, I don't know how to describe it, hot electronics, if you've ever been around something that's got too hot, some wires or whatever that's got too hot. Absolutely, if you start smelling something that sounds like something electronic, some really foreign thing that you're smelling in your listening room, boy oh boy, if you've got the tunes cranking, turn it down, you're going to break something.

Hopefully, that dispels one of the common myths about just because my amp is not as powerful as my speakers will handle doesn't mean you can't still damage them. Thanks a lot for watching. If you have any comments, please include them below.



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