# Speaker wattage against Onkyo Receiver output rating advice



## fiezdude (Jan 28, 2014)

Hi, Hope every one is well. I have been looking for options to upgrade my jamo A 102 satellite speakers with some book shelf speakers which have more fidelity/power and got a local deal for some BIC America FH-65B. What am not sure about is that the power rating considering my onkyo TX-sr313 has 100 W/Ch (6 Ω, 1 kHz,1% THD, 1 Channel Driven, IEC) and the BIC America FH-65B have the power rating as per the screen shot attached. Am also having thoughts of getting Onkyo D-77xx from 1987 but i can get new ones. This is all in view of the power rating of speakers against the specs of a receiver. Very confusing, please help on some light on this. :sn:

ps: Advice an option of the two will be appreciated.



http://www.smarthome.com/82029/BIC-...-Series-Home-Theater-Bookshelf-Speaker/p.aspx

http://www.bicamerica.com/showpage.php?brand=2&type=7&spkrID=114

http://audio-database.com/ONKYO/speaker/d-77xx-e.html


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## hjones4841 (Jan 21, 2009)

I would not worry about the power rating of the speakers unless you plan to play them at full volume all the time. The actual average power in most music and moves is fairly low.

What other members will also tell you is that a speaker can be damaged easily by amplifier clipping. Clipping is the point where you ask the amplifier to produce more power than its power supply will allow. The result is rather harsh square wave (or close to square wave) output which contains many harmonics at high power. Those harmonics (or multiples of the original waveform) are usually outside the rated frequency capability of the speakers. Tweeters are not designed to handle high power; again, the average music or movie power at tweeter frequencies is rather low. So, by putting the amplifier into clipping, it delivers higher power at high frequencies that can fry the tweeter's voice coil. So, it follows that an underpowered amp that is "asked" to deliver more power than it is designed for can damage the rather fragile voice coils of tweeters. So, this is a case for which "more" is "more."

Now, buying an amplifier whose power is grossly over the rating of the speakers does not make sense since it "invites" playing a loud volumes which can generate more heat than the voice coils of other than tweeters can be damaged.

One of the popular "myths" is that an amp rated at 150 watts will sound 1.5 times as loud as a 100 watt one. Not true! The ear is a logarithmic "device." Even double the power is only 3db; many folks can barely tell the difference in hearing 3db.

So, to answer your question, almost any speaker will be OK attached to your receiver. There are exceptions, such as those rated 4 ohms or less, that can cause the receiver to overheat, but that is rare.


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## fiezdude (Jan 28, 2014)

Thank you soo much for your detail response. It has always been a tough debate in my mind about the wattage thing. This brings it out very clear.


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## apilon (May 18, 2006)

Speakers needs to have clean power meaning that for example a speaker rate at 100 watts will need an amp or receiver capable to deliver 150 to 200 watts to provide clean power to the speakers. 

It is more damageable for a speaker not to receive enough power .........And youwill hardly send too much poer to the speakers to blow them out 

Alain


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## lcaillo (May 2, 2006)

I have seen many speakers damaged by too much power. I have also seen many damaged with amplifiers rated lower than the speaker power rating. Severe clipping can be damaging, as can over powering with "clean" power. 

Make sure that the combination plays as loud as you want without distortion and the speakers are appropriately powered. That does not mean that the amp and speaker power ratings need to match. I would typically want at least as much power in the amp as the speaker rating, but only if the speakers are efficient enough to comfortably play as loud as I want without pushing the limits of either the amp or speakers.

It is more about having a system that does what you want it to do cleanly than precisely matching power ratings.


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## fiezdude (Jan 28, 2014)

Thanks guys for the feedback. Second thing, Was trying to understand amplifier clipping and how to avoid it. What occasions does it occur.


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## Almadacr (May 5, 2011)

fiezdude said:


> Thanks guys for the feedback. Second thing, Was trying to understand amplifier clipping and how to avoid it. What occasions does it occur.


Amp or receiver ? Well anyway playing at high levels for long periods can cause clipping and should be avoided but keep in mind that , it can also damage your speakers .


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## fiezdude (Jan 28, 2014)

Receiver mostly. That would be my subject matter at the moment.


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## tonyvdb (Sep 5, 2007)

Distortion and then clipping of the internal amps of the Onkyo can damage speakers. The particular Onkyo would very likely only output 60wattsper channel under load. The best way to help is to set the crossovers on all speakers to small or 80Hz but this is no guaranty that you still would get into distortion when driving it at loud levels.


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## hjones4841 (Jan 21, 2009)

Clipping happens when an amp tries to put out more power than it was designed for. At some point, the power supply just won't do any more and instead of nice clean sine waves, you get some rather nasty almost square waves. The leading and lagging edges of square waves have tons of harmonic content, which is what fries delicate tweeter voice coils. Tweeters normally get only a fraction of the amp power - bass uses most of it. So, when nearly the full output of the amp is aimed at the tweeter via those nasty almost square waves, it cannot handle it.

To avoid clipping, play your music at lower volumes. If it starts to sound distorted, then that is a clue to turn it down.


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## fiezdude (Jan 28, 2014)

tonyvdb said:


> Distortion and then clipping of the internal amps of the Onkyo can damage speakers. The particular Onkyo would very likely only output 60wattsper channel under load. The best way to help is to set the crossovers on all speakers to small or 80Hz but this is no guaranty that you still would get into distortion when driving it at loud levels.


I guess currently i would be safe coz am currently running some 70wat 6 ohms jamo satellites which i have put a crossover setting of 150hz. 80 would be abit too low i think. Maybe for bigger floor standing speakers. Whats your take?

JK


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## tonyvdb (Sep 5, 2007)

Yup, thats a good call as long as the sub your using can go that high.


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## fiezdude (Jan 28, 2014)

hjones4841 said:


> Clipping happens when an amp tries to put out more power than it was designed for. At some point, the power supply just won't do any more and instead of nice clean sine waves, you get some rather nasty almost square waves. The leading and lagging edges of square waves have tons of harmonic content, which is what fries delicate tweeter voice coils. Tweeters normally get only a fraction of the amp power - bass uses most of it. So, when nearly the full output of the amp is aimed at the tweeter via those nasty almost square waves, it cannot handle it. To avoid clipping, play your music at lower volumes. If it starts to sound distorted, then that is a clue to turn it down.


I sually got my sp levels set well just to avoid turning up the volume too high. Tested and every thing sound normal at 90% volume which i would rarely or never turn up to. This is a problem i have noticed with conventional or beginner kit home theaters.

JK


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## fiezdude (Jan 28, 2014)

tonyvdb said:


> Yup, thats a good call as long as the sub your using can go that high.


Hmmm, thats now confusing. The sub has its own cut of frequency adjustment. The receiver crossover doesn't seem to affect the sub connected via sub out.

JK


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## tonyvdb (Sep 5, 2007)

Take the subs crossover and turn it up as high as it will go. The receiver will control the crossover internally.


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## fiezdude (Jan 28, 2014)

tonyvdb said:


> Take the subs crossover and turn it up as high as it will go. The receiver will control the crossover internally.


The sub cut of runs from 40 to 200 hz. I have put it at aprox 120 hz, phase at 0 degrees and level at half. At this point, it sounds ok for all type of music especially acoustics. ( Diana Krall) ;-). Hope these settings are recommended for the speaker types that i uses.

JK


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## tonyvdb (Sep 5, 2007)

You should turn off the crossover on the sub if you can or turn it all the way up to 200Hz
otherwise you can have two crossovers fighting each other.


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## fiezdude (Jan 28, 2014)

tonyvdb said:


> You should turn off the crossover on the sub if you can or turn it all the way up to 200Hz otherwise you can have two crossovers fighting each other.


I think my biggest question would be ( this the manufacturer doesn't seem to say) If the sub pre out is set by the same in built crossover of the receiver. On the jamo sub 210, there is actually no option to switch off the cut of but just a dail from 40-200. If i turn it to 200, the bass sounds too dry/ stiff just to described. There something am not just getting about sub an receiver crossover. Sorry for not being on the same page.

JK


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## tonyvdb (Sep 5, 2007)

Yes, thats possible. What is happening is now your hearing the frequencies that normally a larger speaker would be doing. Because your Speakers are small and only go down to 150Hz your sub is going to have to reach higher than what we would normally like them to. Anything above 80Hz can be heard.


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