Watts per channel vs. Receiver setting ?

JKnPA
JKnPA Posts: 41
edited September 2006 in Speakers
My question concerns the receiver volume setting and the power(watts) going to my speakers!
If I set my Denon receiver to read 0db, how many watts are going to my speakers?
Do I need to measure the 'SPL' at the speakers with a meter, or does my receiver volume setting tell me the power level?
My Denon is rated at 85watts/channel, and my speakers have a range of
20-120w.
Any comments would be apprecited.........
Just received my new Polk speakers!
Beautiful cherry cabinet....
John
Denon 1906AVR
Polk... M40s, Cs1
JVC DVD player XV-SA600
Sharp LC-37D6U
Post edited by JKnPA on
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  • steveinaz
    steveinaz Posts: 19,538
    edited September 2006
    You cannot judge power output by volume level. There's too many varibles; frequency, impeadence, efficiency of the speaker, different output levels of different sources, the list goes on and on.

    The only way to measure output in decibels is with an SPL meter.
    Source: Bluesound Node 2i - Preamp/DAC: Benchmark DAC2 DX - Amp: Parasound Halo A21 - Speakers: MartinLogan Motion 60XTi - Shop Rig: Yamaha A-S501 Integrated - Shop Spkrs: Elac Debut 2.0 B5.2
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  • JKnPA
    JKnPA Posts: 41
    edited September 2006
    Steve,
    Thanks for the reply.
    So the volume reading (receiver window) in dbs means nothing?
    I know an 89SPL reading( Polk speakers) means 1watt of power is delivered to the speakers at a distance of 1meter, and there is a loss of 3db per meter, if you want to measure SPL to your listening position.
    I thought maybe a setting of 0db(receiver) would normally equate to 1watt of power producing 89SPL at a distance of 1 meter.
    see link to 'Education' in Polk questions.......
    http://www.polkaudio.com/education/article.php?id=4
    ***********************************************
    With powered subwoofers and other self-powered speakers, the power rating, whether FTC government approved or WLS (When Lightening Strikes), doesn't really tell you much. Why? Because loudspeaker efficiency is by far the most important factor in determining how loud a system will play. Efficiency (a.k.a. sensitivity) is usually given as the amount of sound produced by 1 watt at a distance of 1 meter. A medium efficiency loudspeaker rating would be around 87 dB from 1 watt at 1 meter. A highly efficient loudspeaker might be 90 dB. Each 3dB increase in efficiency doubles the sound output for a given power input. So a 100-watt, 90 dB self-powered speaker and a 200-watt 87 dB unit would produce exactly the same sound output.

    John...
    Denon 1906AVR
    Polk... M40s, Cs1
    JVC DVD player XV-SA600
    Sharp LC-37D6U
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  • steveinaz
    steveinaz Posts: 19,538
    edited September 2006
    The reading is a ball park guess of the level of attenuation; that's why the louder you go, the smaller the dB attenuation gets. 0 dB would be full output. the SPL (or efficiency rating) of 89dB's means that the speaker puts out 89 decibels of output at 1watt/1meter as measured in an anechoic (soundproof) chamber.

    Remember, it takes a doubling of wattage to increase decibel my 3dB; so with an 89dB speaker, 1 watt=89dB, 2 watts=91dB, 4watts=94dB, 8watts=97dB, 16, 32, 64...and so on....you can see how quickly amplifier power gets eaten up.
    Source: Bluesound Node 2i - Preamp/DAC: Benchmark DAC2 DX - Amp: Parasound Halo A21 - Speakers: MartinLogan Motion 60XTi - Shop Rig: Yamaha A-S501 Integrated - Shop Spkrs: Elac Debut 2.0 B5.2
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  • JKnPA
    JKnPA Posts: 41
    edited September 2006
    Steve,
    The Denon actually has a range of -70 to + 18db.
    That is why I asked about the power output at 0db.
    If I set the volume to 0db, that seems just about a normal listening
    level from 10ft. away from the speakers.
    Since all of us have different hearing capabilities, we would have different volume level settings for our 'normal level'.
    I was just trying to determine the near maximum level before the speakers were being stessed!
    JK
    Denon 1906AVR
    Polk... M40s, Cs1
    JVC DVD player XV-SA600
    Sharp LC-37D6U
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  • michael_w
    michael_w Posts: 2,813
    edited September 2006
    It's pretty tough to determine that level by just looking at spl, wattage and the little numbers on your receiver. I would be more concerned about pushing your receiver too hard and clipping it.
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  • Frank Z
    Frank Z Posts: 5,860
    edited September 2006
    I know an 89SPL reading( Polk speakers) means 1watt of power is delivered to the speakers at a distance of 1meter
    Close. One watt supplied to a speaker with an efficiency of 89db will generate an 89db signal at 1 meter from the speaker.
    9/11 - WE WILL NEVER FORGET!! (<---<<click)
    2005-06 Club Polk Football Pool Champion!! :D
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  • F1nut
    F1nut Posts: 50,494
    edited September 2006
    JKnPA wrote:
    Steve,
    The Denon actually has a range of -70 to + 18db.
    That is why I asked about the power output at 0db.
    If I set the volume to 0db, that seems just about a normal listening
    level from 10ft. away from the speakers.
    Since all of us have different hearing capabilities, we would have different volume level settings for our 'normal level'.
    I was just trying to determine the near maximum level before the speakers were being stessed!


    The dB scale on your AVR is just a guide with 0 being "reference level" as determined by Denon. The power output will vary as Steve indicated.

    Maximum level will be recognized by you very quickly as everything will start to sound like crap.
    Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a t-u-r-d by the clean end."

    President of Club Polk

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  • JKnPA
    JKnPA Posts: 41
    edited September 2006
    Thank you for all the quick replies......... ;)
    Nice website...............

    John
    Denon 1906AVR
    Polk... M40s, Cs1
    JVC DVD player XV-SA600
    Sharp LC-37D6U
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  • reeltrouble1
    reeltrouble1 Posts: 9,312
    edited September 2006
    I guess you could get close if you measured the SPL at 0 on the relative scale at 1 meter, knowing it takes 1 watt to get a reading of 89 you could keep doubling the watts for every 3db increase until you get to where ever you found the measurement at 0. I suspect it will be fairly close.

    It might be fun to do but is really not necessary as stated the scale is just a reference point.

    RT1
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  • jdhdiggs
    jdhdiggs Posts: 4,305
    edited September 2006
    Frank Z wrote:
    Close. One watt supplied to a speaker with an efficiency of 89db will generate an 89db signal at 1 meter from the speaker.

    and only @ 1 frequency... Typically 1Khz
    There is no genuine justice in any scheme of feeding and coddling the loafer whose only ponderable energies are devoted wholly to reproduction. Nine-tenths of the rights he bellows for are really privileges and he does nothing to deserve them. We not only acquired a vast population of morons, we have inculcated all morons, old or young, with the doctrine that the decent and industrious people of the country are bound to support them for all time.-Menkin
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  • JKnPA
    JKnPA Posts: 41
    edited September 2006
    If I use an 'SPL' meter, will I be getting an 'average' reading for the audio range I am listening to? If so, wouldn't that give me a more accurate (realistic) idea of the audio(music) level I am hearing?
    I'm just trying to get a general idea of the power going to the speakers, not in tuning the speakers for bass/mid/tweeter response.
    I know you can buy 'test disks' to tune your system, but that is not what I want!
    If I set the receiver to 0db reading, and place the 'SPL' meter a distance of 1meter from the center speaker....... that should give me a general idea of the power at the speaker vs. the 'SPL' reading.
    Would that be fairly accurate or not ???
    JK.
    Denon 1906AVR
    Polk... M40s, Cs1
    JVC DVD player XV-SA600
    Sharp LC-37D6U
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  • JKnPA
    JKnPA Posts: 41
    edited September 2006
    I think I'll buy a 'SPL' meter and do some measurements!
    Perhaps I will buy an audio test disk, if it proves interesting.
    I found this link in another section of this site........
    http://www.audiophilia.com/hardware/spl.htm

    JK.
    Denon 1906AVR
    Polk... M40s, Cs1
    JVC DVD player XV-SA600
    Sharp LC-37D6U
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  • michael_w
    michael_w Posts: 2,813
    edited September 2006
    That's basically the same spl meter I have as well. Despite being the same one my dad used thirty years ago when he was into audio it's still alive and kicking (probably needs to be recallibrated though).

    I think you'll find you're only actually using a watt or two when listening to loud music. To test the power going to your speakers you might get better results with a multimeter. SPL meters are generally used more for calibration and fiddling around. It would be hard to accurately figure out how much power you're using with an spl meter just because there are so many variables (eg room gain) but you could probably get a small idea.

    Search around for an Avia disk. Never used one myself but they seem to be the standard for calibration tests.
    Avia guide to HT
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  • JKnPA
    JKnPA Posts: 41
    edited September 2006
    Mike.....
    I found this yesterday. http://www.svsound.com/products-parts-avia.cfm

    Since I'm at a 'Polk' website, I won't mention the other sub!..:rolleyes:
    Denon 1906AVR
    Polk... M40s, Cs1
    JVC DVD player XV-SA600
    Sharp LC-37D6U
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