Frequency Response question

Josh-S
Josh-S Posts: 160
edited November 2005 in Speakers
I have noticed that some specs have this,

Overall Frequency Response 38Hz - 25kHz
Lower -3dB Limit 48Hz
Upper -3dB Limit 24kHz


What does the red ones mean? Sorry, this is al new to me... :o
Post edited by Josh-S on
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Comments

  • jdhdiggs
    jdhdiggs Posts: 4,305
    edited November 2005
    The red ones are real, the others represent areas where the speaker may be making some sound, but is no longer in a flat frequency response area. Typically you would only want to look at the -3db specs. Remember that the response curves are not neccessarily indicative of the quality of sound a speaker can produce.
    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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  • PolkThug
    PolkThug Posts: 7,532
    edited November 2005
    It means that the amplitudes are 3 decibels lower than the average at those frequencies. As the decibels decrease the speaker is less effective at those frequencies and beyond. The number basically give you an effective operating range of the speakers.
    Never Forget
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  • steveinaz
    steveinaz Posts: 19,538
    edited November 2005
    Generally (but not always) your "overall" response is measured at -10dB points. Still audible, but at less than a third of the output. The +/-3dB spec is popularly used because its thought to be threshold of hearing a difference in amplitude.
    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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  • ND13
    ND13 Posts: 7,601
    edited November 2005
    Isn't that where the fall off begins??
    "SOME PEOPLE CALL ME MAURICE,
    CAUSE I SPEAK OF THE POMPITIOUS OF LOVE"
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  • steveinaz
    steveinaz Posts: 19,538
    edited November 2005
    Technically a speaker should remain +/-3dB within its rated frequency response to be considered a fairly flat response. Of course none of this has much to with "real world" in-room response, unless your living room is the perfect environment.
    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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  • Josh-S
    Josh-S Posts: 160
    edited November 2005
    As always, you are all a great help! :D
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