The proper specs of subwoofers

Hi, I am considering to buy XT10/XT12 subwoofer.
One problem is there is no information about the specs / measurement.
The official datasheet says it can play 24hz. So is the frequency response is 24hz~ ?
What is Lower and Upper -3dB Limits of xt10 and xt12?

Sorry for my bad english.
Thank you for reading.

Comments

  • F1nut
    F1nut Posts: 49,704
    XT12 Specs

    built-in 50-watt RMS Class AB amplifier (100-watt peak)

    bass-reflex (ported) enclosure

    braced MDF cabinet minimizes resonance for clean bass

    frequency response: 24-160 Hz

    low-pass crossover: 80-160 Hz

    phase switch: 0/180°

    line-level stereo RCA input

    spring clip speaker-level input and output
    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

  • hans_
    hans_ Posts: 2
    Thank you for replying.
    My question is 'frequency response: 24-160 Hz'.
    Is that Lower and Upper -3dB Limits data?
    So offical Lower and Upper -3dB Limits frequency response of xt10 and xt12 is 24-160 Hz, right?
  • Emlyn
    Emlyn Posts: 4,346
    edited January 2023
    Polk only lists the overall frequency response in the manual and on the website for the XT10 and XT12. One could guess the -3dB lower frequency limit of an XT10 as being somewhere around 40 Hz based on other similar sized and powered models from Polk that have listed the frequency responses. That's only a guess but room gain from placement will also play a factor in the sub's performance. The XT subs are designed to integrate well with the XT line of budget speakers. The XT subwoofers will be nowhere near a clean 24 Hz signal in real world use but they'll be ok with the speakers they're designed to integrate with.
  • Clipdat
    Clipdat Posts: 12,557
    edited January 2023
    If they don't publish the -3db detailed specifications and/or frequency response charts, there's probably a reason for that.

    It's a cheap 12" woofer with a 50w RMS amp. It's not going to be doing anything with any sort of authority around 24hz.

    Save up your money and put it toward something that doesn't just make boom boom sounds.
  • mhardy6647
    mhardy6647 Posts: 32,922
    All generalizations are false, including this one ;) -- but, generally, when frequency "range" or response is quoted without limitations (i.e., +/- "x" decibels), the implied limitation is - 10 dB. Minus 10 dB is ten times quieter than the zero dB ('flat') output level, so... yeah... such specifications are pretty much meaningless.
    @Emlyn's post pretty well covers the bases.
  • Gardenstater
    Gardenstater Posts: 4,133
    edited January 2023
    I read an article by an ex Polk employee (Sales manager?, RIP) with a name I cannot remember (at the moment) where he stated that when Polk gave no dB qualifiers it meant -9dB. That may have changed since then for all I know but just putting that out there.

    PS: I remember the name now. Paul DiComo. You could do a search on the forum and I believe I posted the article here at some point in time....

    Found it: https://www.ecoustics.com/articles/understanding-speaker-frequency-response/

    "How Polk Specifies Frequency Response
    Polk Audio publishes two frequency response specifications: “Overall” and “-3dB.” “Overall” describes the frequency range limits of the speaker within an amplitude drop off of 9dB. Any frequency reproduced more than 9dB down from the rest of the frequencies will contribute little to the sound. The “-3dB” spec describes the frequency range limits of the speaker within an amplitude drop off of 3dB."
    George / NJ

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