Can a power amp have too much power, risking damage to a speaker?

@joelepo Wrote:

Can a power amp have too much power, risking damage to a speaker?

See full article here!

Mike

Of course. Don't try this at home.
My 100 Watt MF integrated completely melted the midrange drivers of a pair of brand new Hyperion speakers.

Thanks much Mike for that info! I'll look for an amp with much lower powered if I get speakers with limited power handling capacity. 

NO!

Too much power generally isn’t an issue when pairing hi-fi /home theater speakers and amplifiers. It’s the opposite situation—too little power—that can create problems. When an amplifier is driven into clipping (distortion) by being asked to produce more power than it’s capable of delivering, the voice coil of the speaker it’s attached to can overheat and become damaged. That said, an RMS power rating on a speaker doesn’t even begin to tell the whole story. Two other specs, sensitivity and impedance, are much more important in determining how much power a particular speaker requires to deliver sufficient volume levels.

Ya, too much gain.

Rock "in" Roll

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You'll likely damage your hearing before the speakers 

Technically yes, you could damage your speakers with over wattage, but as someone stated, your ears would probably be damaged first. There is more risk with an underpowered amp that starts clipping at high volumes, this will trash your speakers much faster. 

THANK ALL of you for usefully responding to my query.
My overall take-home: an underpowered amp driven to clipping seems more likely to damage a speaker than clean power that controls the linear motor of audio transducers. An amp driven at its upper limit is more likely to clip tops of waves, causing the voice coils to stay in one position just drawing current [may not have said it perfectly]. 
I still have great hearing even after being in a rock band during my 20s [took great care to protect ears during all performances], and we often get out an audiometer to ensure the sound-pressure-level is well under 95dBA for sustained periods. So far, so good! 

There is no such thing as too much power. It is far more common for an underpowered amp to destroy speakers with clipping which can easily overheat fragile voice coils.

High powered systems are always limited unless you like destroying your ears. K horns will easily destroy your ears before they get into trouble. 

Thanks! mijostyn! 
I follow some Audiogon discussions, but this is my first time to submit a query.
Impressed that there are folks out there who as OCD perfectionist regarding good audio as I! 
Based on this experience, I'll likely join some other discussions groups. It's a great community! 
 

Amplifiers can damage loudspeakers with too much sustained high power.  If you treat your loudspeaker's voice coils as if they were a fuse, they will eventually fail.  Use some common sense. 

sometimes these discussions leave me speechless

It really can. I've damaged my speakers with large power!

I’ve always had power amps that far exceeded the power handling capacity of my speakers. Never damaged a speakers. Particularly with solid state amps most speakers benefit from having large excess capacity, yielding more solidity.

As my systems got better the volume of maximum enjoyment went down, until now 65db to 75db is typical… cracking 80 if I am enjoying it really loud..

....nothing like the fragrance of fused voice coils to flip enthusiasm into ennui...

Note that any tube guitar amp from a 5 watt studio amp to a 100 watt whatever will often be used overdriven with distortion into the speakers for DECADES with no harm done. If people are lame enough to drive their delicate little home stereo speakers to the edge with a high powered amp (especially a solid state one) there's little to be done for them.

As pointed out in one of the threads, when the maximum power of an amp is reached, the distortion rises very quickly. It is a "bell" curve rise. The distortion goes from "zero to a hundred" really fast (smallest movement of the volume control), and the distortion created plays havoc with the tweeter/s and midrange speakers.

Not so much with a group like this, but what I saw with the "how loud will it go" crowd was, they "cracked it" and after a while the tweeter went. Five to ten percent of the sound was lost, so they "cranked it" again.  A short time later there was less sound again because the mids were fried.

Woofers pretty much have to be abused with brute over powering or "bottoming" them out with excessive bass and power. I had knuckle heads complain that their speakers were  making a "whip cracking" sound, or a "blatty" sound. As it turns out, they have the loudness button in, bass control cranked to the max, and  the volume control at 3:00 (because that's only 3/4's of the way up, it should be able to do that).

In my experience, less than 5% of the time did speaker repairs result in a woofer failing.

To go along with that, I saw more blown speakers caused by them being under powered, than over powered, and that goes back to how the distortion increases when full volume is reached..

As for the guitar amp being over driven, in most cases you are dealing with a speaker that is basically a woofer. The distortions being generated by the "stomp boxes" are in the mid and upper range frequencies. This is not really taxing or putting the speaker in any danger. 

I have a pair of B&W speakers that have a recommended power of 50 to 300 watts. I'm driving the pair with a 120 watt tube monoblock amp attached to each. Other than having to chase down a ground loop issue (which I solved the other night), this setup is flawless. It may be "underpowered" but sure does not sound like it. I may build two more monoblocks and Bi-amp the speakers, for now, I have no need and it sounds amazing.

@joelepo wrote:

I have a McIntosh 402, rated 400 watts continuous per channel. If I use it to drive a pair of Klipshorns or LaScala [specified to handle 100 watts continuous] or similar high-efficiency speakers, do I risk damage to such speakers?

The La Scala’s are just around or slightly above 100dB’s measured sensitivity, and so would be very loud even with limited power supplied by the McIntosh; practically you likely won’t get to where your speakers are challenge thermally let alone mechanically, whereby the power in reserve will come in handy with loads of headroom (which is a good thing). However, something tells me the La Scala’s thrive on tube-based amps, preferably moderate to higher powered variants, so that might be worth experimenting with.

With inefficient and passively configured speakers in general (and most are), I’d recommend at least double the amp output power of the speaker’s long term max. power handling capacity. Less SPL requirements/shorter listening distance/more lively damped rooms can do with less amp output power.

Efficient and typically passively configured speakers of yore/vintage origins or inspired (with lower to moderate power handling) seem to thrive on and get by with low powered amps, tube-based in particular, whereas more modern and pro segment high efficiency speaker designs with larger voice coils and stiffer suspensions like to be fed by high powered SS amps - they simply come better and more assuredly to life this way, not least actively. Both approaches have their strengths; the former can come across seemingly a bit more lively and with more character, while the latter has the more solid and, to my ears, "neutral" and resolved imprinting. I prefer the latter camp for a variety of reasons, but I can appreciate either approach.

Thanks all for contributing to my education.
I play guitar and 5-string bass and have one Fender Pro tube amp with twin 10" speakers and a Fender SS Bassman with four 10" speakers. Guitar amps and speakers differ from high-fidelity amps and speakers. The former are designed to "produce 'music'" -- so as long as they hold together and generate the sound the musician want, all is OK. In contrast, seems to me that "high fidelity" speakers should not contribute any of their own voice to the sound that comes out. I KNOW... achieving that ideal is far more complicated than that. 

I've been playing electric bass for decades and I have a couple of pro bass amps (15s, 12s, mondo pro sub) and one learns that there's obvious limits on how loud you can play before the speakers get annoyed. Is this too basic? Over 6 maybe? Electric Bass teaches an interesting tone exercise.

Yes, but the speakers will hurt you before you can hurt them.

"we often get out an audiometer to ensure the sound-pressure-level is well under 95dBA for sustained periods."

This would be less than ONE WATT fed to your Klipsch speakers. I think you’re good.

A little historical context:

When Bose 901s were first introduced to the audio world, they had a power rating of 270 watts (If memory serves correctly). They were having incidences of catastrophic driver failure. A quick study revealed that little Pioneer receivers (around 10 WPC true RMS power) were the culprit. These little boxes were, essentially, turning into low amperage DC power supplies at sustained clipping for long periods of time (hours). Bose raised the "recommended" minimum amp power rating to 50 WPC. Problem solved.

@waytoomuchstuff  That is exactly right. Too little power is more likely to do damage than too much, but there are some caveats that most audiophiles are aware off. With high powered systems it is stuff like dropping the tonearm on the record with the volume up. Or switching to a higher gain source with the volume up. 

waytoomuchstuff: old enough to be familiar w the Bose901power issues. 

To mijostyn and others who warn about TOO LOUD sound: We use an audiometer to monitor our listening room and most of our listening is below 70dB; if we are watching an action movie with lots of special effects, we find transient peaks of 100dB or more. A few minutes a day of over 95dB is unlikely to  cause permanent damage.

BTW, the new Apple Watches have an App that monitors SPL and seems to deliver readings pretty close to what I get from our more sophisticated audiometer. 

Doing some quick math here, your Mac and K'horns or LaScalas should hit peaks of over 130 decibels in your room. Should be plenty of dynamic range available on demand.

agree... with your math😁. And will not even approach 130db in our theater. 

About 30 years ago a dealer (who shall remain nameless) in Philadelphia told me that basically, "Too much clean power has never hurt a speaker."  He told me a lot of other things that I suspect would get pushed back on here.

JBL warns about loud levels. See JBL studio monitor technical manual here last page caution section SPL!

Mike