SDA1b refurbish.

vintagenut
vintagenut Posts: 28
edited January 2014 in Vintage Speakers
Please forgive me if this has already been asked, but I could't really find my exact answer in the forum. I have a set of SDA1Bs that i really love. The speakers sound very good and have no known issues. I realize there are several ways to mod the crossovers etc. But I really just wan't to know if my 1Bs are still performing about as well as when they were new. I did read in the forum that some of the caps age and others not so much.. Is there any way for me to check the crossovers with a multi meter to see if there in spec? With my limited experience in de-soldering and re-soldering I would feel comfortable replacing a cap or two, but that's about it. Or do I need to take the crossovers out and send them somewhere for the work to be done? Anyone here interested in doing the work if I do? I am willing to spend some money to have them back to spec but don't want to spend more than I have to. Thanks for any help.
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Comments

  • F1nut
    F1nut Posts: 50,554
    edited January 2014
    There's a million posts here about SDA crossver upgrades. Bottom line, replace all caps and resistors regardless of the condition of your originals.
    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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  • bigaltx24
    bigaltx24 Posts: 141
    edited January 2014
    They'll sound a lot better with good quality film caps, Mills resistors and bypassing the polyswitch. If you've done any soldering, it's not hard to rebuild crossovers. If you decide to tackle the job, make sure to take pictures or draw yourself pictures of where everything goes before you pull them apart.
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  • GlennDog
    GlennDog Posts: 3,120
    edited January 2014
    vintagenut wrote: »
    But I really just wan't to know if my 1Bs are still performing about as well as when they were new. I did read in the forum that some of the caps age and others not so much.. Is there any way for me to check the crossovers with a multi meter to see if there in spec?

    After all these years, I highly doubt they could ever perform as designed. You need to mod all aspects of these speakers. They may sound good/great but can sound MUCH better!
    vintagenut wrote: »
    Or do I need to take the crossovers out and send them somewhere for the work to be done? Anyone here interested in doing the work if I do? I am willing to spend some money to have them back to spec but don't want to spend more than I have to. Thanks for any help.

    Reach out to Trey (VR3Mods.com) He can do the X-over upgrades for you
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  • drumminman
    drumminman Posts: 3,396
    edited January 2014
    The Xover mods are not difficult. One tip is to pull both boards out and replace the caps and resistors (I recommend doing the inductors too) on one board while using the other as a reference. What you're doing essentially is swapping parts.

    If you order a set of Gimpod's boards it will be much easier (more room) than using the stock ones. Trey has a great reputation around here for Xover rebulds.

    Good luck and feel free to post questions.
    "Science is suppose to explain observations not dismiss them as impossible" - Norm on AA; 2.3TL's w/sonicaps/mills/jantzen inductors, Gimpod's boards, Lg Solen SDA inductors, RD-0198's, MW's dynamatted, Armaflex speaker gaskets, H-nuts, brass spikes, Cardas CCGR BP's, upgraded IC Cable, Black Hole Damping Sheet strips, interior of cabinets sealed with Loctite Power Grab, AI-1 interface with 1000VA A-L transformer
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  • Schurkey
    Schurkey Posts: 2,101
    edited January 2014
    drumminman wrote: »
    The Xover mods are not difficult. One tip is to pull both boards out and replace the caps and resistors (I recommend doing the inductors too) on one board while using the other as a reference. What you're doing essentially is swapping parts.
    Don't be afraid to do this yourself. Polish your wire-soldering skill on some wire scraps, and then have some fun. Made a HUGE improvement to my 1Bs.

    Depending on who you talk to, the SDA 1B can take the RD0-198 tweeters with a simple and cheap High-frequency crossover modification. I did this with mine. (Remove 4.4uF capacitor, replace with 5.8uF cap on each HF circuit board. 5.6uf is easier to find, and satisfactory)

    The new caps are much larger than the old ones, you'll have to be creative to get it all to fit on the circuit board.

    My 1B low-frequency crossover and parts:
    PolkLF_CapacitorComparison2SM.JPG

    PolkLF_FinishedSM.JPG

    drumminman wrote: »
    If you order a set of Gimpod's boards it will be much easier (more room) than using the stock ones. Trey has a great reputation around here for Xover rebulds.
    DO NOT order Gimpod's boards, as they are not compatible with the SDA 1B.
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