overpowering speakers.

[Relishh13]

Hi, I didn't see anything like this posted but will ask.I am wondering about receiver /amp power vs speaker handling power. If say a amp puts out 110 at 8 ohms/150 at 6(these are continuous) all channels driven. what would the power handling of the speakers need to be. I have seen that front r/l are usually higher than center,but why is this does not the center need to be the same considering it's job.I am looking at a few specific models but don't want to end blowing the damn things if I get them. the ratings were front 15-120..center 15- 80 surrounds 15-90.Now if these were put with this amp wouldn't it blow the center and surrounds?...Any pointers or links or anything is really appreciated.

 

[j_garcia]

There is pretty much NO SUCH THING as over powering speakers (there IS such a thing, but it is highly unlikely in normal use). In general, clean power will NOT fry speakers, not to mention you aren't going to use 100% of the amps power all the time to drive them at typical listening levels. During normal listening, you are using maybe 5-10 watts of that 110 total; that power is needed to handle dynamic peaks when things get heavy, so power is a good thing to have in reserve. In other words, as long as you have sufficient power to drive your speakers to the level that you want without distortion, you will be fine.

The other side of that coin, especially when talking about receiver's amps, is that their ratings are almost always optimistic at best.

 

[Pyrrho]

Hi, I didn't see anything like this posted but will ask.I am wondering about receiver /amp power vs speaker handling power. If say a amp puts out 110 at 8 ohms/150 at 6(these are continuous) all channels driven. what would the power handling of the speakers need to be. I have seen that front r/l are usually higher than center,but why is this does not the center need to be the same considering it's job.I am looking at a few specific models but don't want to end blowing the damn things if I get them. the ratings were front 15-120..center 15- 80 surrounds 15-90.Now if these were put with this amp wouldn't it blow the center and surrounds?...Any pointers or links or anything is really appreciated.

When looking at power ratings of amplifiers, they are giving maximum power with particular levels of distortion (as the power goes up beyond the maximum RMS ratings, distortion levels tend to rise rapidly). The amplifier is NOT putting out that power always whenever you turn it on; the amount of power it is putting out at any moment is dependent on the input level (which, being music, is somewhat variable) and the position of the volume control. So an amplifier rated for 1000 watts may be putting out less than 1 watt, depending on the input level and the volume control setting. So you can use a powerful amplifier with speakers that cannot handle the total power that the amplifier is capable of putting out.

Basically, whenever the sound starts to become audibly distorted, you should turn down the sound. That, however, will not tell you whether the distortion is due to the amplifier reaching its limits, or the speaker reaching its limits, or both.



Unfortunately, power ratings for speakers are not standardized, and so they mean virtually nothing for comparing between different brands. If you are interested in details regarding power and what it takes to destroy speakers, here are some links:

http://www.audioholics.com/education/loudspeaker-basics/loudspeaker-power-handling

http://www.audioholics.com/education/loudspeaker-basics/loudspeaker-power-ratings

http://www.audioholics.com/education/loudspeaker-basics/loudspeakers-power-ratings-part-iii-the-test-results

 

[highfigh]

Speakers can be damaged by excessive power but it's probably more rare than from clipping or some kind of oscillation. Overpowering speakers usually can be seen in woofers first, because the excursion goes beyond what they're designed for and also in thermal compression, which is due to the voice coil becoming hot and resisting current flow more than at normal temperatures. A conductor has some resistance and that will vary with temperature, increasing as the temperature rises. This shows up as a decrease in SPL at any power level when compared with lower voice coil temperature. Dynamics are reduced and in extreme cases, the SPL drops considerably.

 

[KEW]

Hi, I didn't see anything like this posted but will ask.I am wondering about receiver /amp power vs speaker handling power. If say a amp puts out 110 at 8 ohms/150 at 6(these are continuous) all channels driven. what would the power handling of the speakers need to be. I have seen that front r/l are usually higher than center,but why is this does not the center need to be the same considering it's job.I am looking at a few specific models but don't want to end blowing the damn things if I get them. the ratings were front 15-120..center 15- 80 surrounds 15-90.Now if these were put with this amp wouldn't it blow the center and surrounds?...Any pointers or links or anything is really appreciated.

Forget the ratings.
The easiest thing to do is to get the place you are buying them from to pair the speakers you want with the weakest receiver you'd consider and make sure it plays louder than you would ever play it in your house without maxing out the volume!
If you end up with a more powerful receiver, that is no problem because you are still not going to turn it up louder than you did in the store.

 

[Relishh13]

Thanks everybody for the info.I think I have made a decision on what speakers I'm getting.By the way I have http://www.pioneerelectronics.com/PUSA/Home/AV-Receivers/Elite+Receivers/VSX-81TXV.The question was based on whether I would have any problems with this thing killing off a 5.1 set up of mordaunt short I was looking at.I think I'm going to end up with a 5.1 scratch and dent from EMP.I t 'll save a little cash.I hope the b-stock from them isn't too bad off.Oh and Pyrrho thanks for the links I'm kinda geeky about that stuff anyway.

 

[Relishh13]

http://www.pioneerelectronics.com/PUSA/Home/AV-Receivers/Elite+Receivers/VSX-81TXV

 

[Pyrrho]

Thanks everybody for the info.I think I have made a decision on what speakers I'm getting.By the way I have http://www.pioneerelectronics.com/PUSA/Home/AV-Receivers/Elite+Receivers/VSX-81TXV.The question was based on whether I would have any problems with this thing killing off a 5.1 set up of mordaunt short I was looking at.I think I'm going to end up with a 5.1 scratch and dent from EMP.I t 'll save a little cash.I hope the b-stock from them isn't too bad off.Oh and Pyrrho thanks for the links I'm kinda geeky about that stuff anyway.

If you keep the volume down, you will not overpower the speakers. I used a receiver rated at 160 watts RMS continuous per channel (an old Pioneer SX-1250) with speakers that were rated for about half that power. I used that system for more than a decade, with no problems ever. Most of my current systems involve amplification whose abilities exceed what the speaker manufacturers recommend (I have 4 systems set up in my home). I have never damaged a speaker from doing this, and I have had various systems for a few decades now.

Generally speaking, you can find out about how loud you can play a system by putting on music that is at a fairly constant level, and slowly turning up the volume until you start to hear distortion, and then turn it down until the distortion goes away, and you have found what is likely your maximum safe volume (though obviously playing it that loud all day could lead to excessive heat). Keep in mind, that does NOT mean that you will always be safe with the volume control at that setting, because a higher input at that setting will result in the amplifier putting out more power.

But it does give you a kind of reference point, and if that is not loud enough for you, you either need more sensitive speakers, or speakers that can handle more power, or a more powerful amplifier. Or, if you are one of the many crazy people who literally listen at levels that are so loud that they do permanent damage to their hearing, you should learn to enjoy music at safe levels instead, unless you don't want this to be a lifelong hobby and would like to end your days with a hearing aid and even then not hearing well while using that aid.