LSI25 sound difference

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Hello,
I'm hoping someone here might have some good advice for me because i'm feeling pretty lost at this point. I have recently purchased a pair of LSI25s used, for what I thought was a good deal (at the time). However, after getting them home and listening to them using multiple amplifiers it is clear that one speaker is louder than the other. I switched the drivers from one speaker to the other and nothing changed, the left channel stayed louder. However, when I switched the crossover, the right channel became the louder one. Thinking I had discovered the problem I took the crossover to a local electronics repair shop who tested the components and found them to be perfectly in spec, leaving me pretty baffled. He also was unable to think of a reason for the difference and agreed something was pretty strange. Now ive also noticed a couple other differences between the two. When looking at the driver dates it is clear that one speaker was made probably 3-4 years before the first based on dates on drivers and internal components, and the subwoofer drivers have a different appearance and one is deeper than the other by about 1/2 an inch even though they have the same part #. My main question is would it be possible for the difference in sound to be due to a late model vs early model having a slightly different sound? or should I stay with my feeling that the crossover is the problem (not that I can find one anyway). I love the sound of the louder speaker and would appreciate any help to restore these speakers to the way they should sound if possible. Thanks.

Comments

  • F1nut
    F1nut Posts: 49,801
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    The schematic is posted in this thread, https://forum.polkaudio.com/discussion/38755/polk-audio-speaker-wiring-schematics-amp-more-all-models-except-sda

    You're going to have to compare everything between the two speakers including the subwoofer amps. I'm unaware of any changes during production, but anything is possible.
    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

  • skrol
    skrol Posts: 3,338
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    The speaker drivers should have stickers with the model numbers. Are they the same between the two speakers?
    Stan

    Main 2ch:
    Polk LSi15 (DB840 upgrade), Parasound: P/LD-1100, HCA-1000A; Denon: DVD-2910, DRM-800A; Benchmark DAC1, Monster HTS3600-MKII, Grado SR-225i; Technics SL-J2, Parasound PPH-100.

    HT:
    Marantz SR7010, Polk: RTA11TL (RDO198-1, XO and Damping Upgrades), S4, CS250, PSW110 , Marantz UD5005, Pioneer PL-530, Panasonic TC-P42S60

    Other stuff:
    Denon: DRA-835R, AVR-888, DCD-660, DRM-700A, DRR-780; Polk: S8, Monitor 5A, 5B, TSi100, RM7, PSW10 (DXi104 upgrade); Pioneer: CT-6R; Onkyo CP-1046F; Ortofon OM5E, Marantz: PM5004, CD5004, CDR-615; Parasound C/PT-600, HCA-800ii, Sony CDP-650ESD, Technics SA 5070, B&W DM601
  • Sandyman14
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    Same model number non consecutive serials. I'm getting a dead link for the schematic.
  • F1nut
    F1nut Posts: 49,801
    edited June 2019
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    I see what you mean, oh well.
    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

  • Sandyman14
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    Anyone have an idea what i should be checking/ have the XO schematic? Any help would be very appreciated.
  • F1nut
    F1nut Posts: 49,801
    edited June 2019
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    You'd have to pull everything to compare components, but as you already noted they are years apart and have different subwoofers, so it's obvious they are a mismatched pair. As parts such as the subwoofer are not available it may simply be time to punt.
    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

  • polrbehr
    polrbehr Posts: 2,826
    edited June 2019
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    Didn't I read somewhere that there was a drop-in replacement subwoofer for these? I could have sworn some folks swapped in different drivers, maybe like an 8" car audio sub? If it won't cost too much to try, it may be worth it.

    *eh, maybe not, I see the OP swapped Xovers and the problem was still there.

    So, are you willing to put forth a little effort or are you happy sitting in your skeptical poo pile?


    http://audiomilitia.proboards.com/
  • txcoastal1
    txcoastal1 Posts: 13,132
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    polrbehr wrote: »
    Didn't I read somewhere that there was a drop-in replacement subwoofer for these? I could have sworn some folks swapped in different drivers, maybe like an 8" car audio sub? If it won't cost too much to try, it may be worth it.

    *eh, maybe not, I see the OP swapped Xovers and the problem was still there.

    That was the LSi15 not the 25's
    2-channel: Modwright KWI-200 Integrated, Dynaudio C1-II Signatures
    Desktop rig: LSi7, Polk 110sub, Dayens Ampino amp, W4S DAC/pre, Sonos, JRiver
    Gear on standby: Melody 101 tube pre, Unison Research Simply Italy Integrated
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