SDA-1 midranges subdued- recap?

Love my SDA-1 C's, and feel a loyalty to them after I put in new RD0194's in and (thanks to @lawdogg 's seized woofer thread) fixed three of the of the seized woofers. I want to keep them, but the only thing bugging me is a noticeably subdued lower midrange (piano and horn elements are just really quiet compared to the rest of the instruments). Is this something that a recap might fix? I'm bot very savvy with electronics, but I did replace the caps in my old Klipsch Heresy's. (though that was a super simple swap out).

SO:

1. Would recapping SDA-1 C 's potentially help with subdued midrange?
2. If so, is it a pretty easy recap?

Thank all!

Answers

  • Gardenstater
    Gardenstater Posts: 4,136
    I have heard that electrolytic capacitors especially, when they age their ESR (effective series resistance) can go up dramatically. I'd wager that could throw off the voicing in speakers. Upgrading the capacitors and resistors will work wonders, especially if you also upgrade the internal wiring and binding posts. Just my 2c.
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
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  • robosdad
    robosdad Posts: 48
    Thanks @Gardenstater Is it pretty easy and inexpensive to replace the capacitors and resistors? Like I said, I did them in my heresy's, but they were super simple and I'm a little leary that the SDA-1 will be beyond me (though I hope not and am willing to try if there's not a huge chance or ruining them).
  • Schurkey
    Schurkey Posts: 2,100
    edited March 2023
    The Polk SDA crossovers can be more-complex than what is used on other speakers.

    Doesn't matter. Process is the same, you may be working longer to get all the parts changed. Figure out what capacitors, resistors, and (maybe) inductors you want to replace, do one crossover at a time, and have fun.

    Rebuilding the crossovers on my 1Bs made them much more enjoyable.
  • robosdad
    robosdad Posts: 48
    Schurkey wrote: »
    The Polk SDA crossovers can be more-complex than what is used on other speakers]

    Doesn't matter. Process is the same, you may be working longer to get all the parts changed. Figure out what capacitors, resistors, and (maybe) inductors you want to replace, do one crossover at a time, and have fun.

    Rebuilding the crossovers on my 1Bs made them much more enjoyable.

    Awesome- thanks. I'll start researching it, but if you know of any good resources (especially ones written for a beginner) please let me know. At this point I don't even know what or where to order (for the Heresy's I bought a kit). Thanks!
  • Gardenstater
    Gardenstater Posts: 4,136
    robosdad wrote: »
    Thanks @Gardenstater Is it pretty easy and inexpensive to replace the capacitors and resistors? Like I said, I did them in my heresy's, but they were super simple and I'm a little leary that the SDA-1 will be beyond me (though I hope not and am willing to try if there's not a huge chance or ruining them).

    If you have done the process on a smaller scale I don't think you should have any trouble. The most recent person to do this on the SDA 1C was @plasticavatar and you can read his thread for some info. and people advised him who had done it.
    George / NJ

    Polk 7B main speakers, std. mods+ (1979, orig owner)
    Martin Logan Dynamo sub w/6ft 14awg Power Cord
    Crown D150 amp
    Logitech Squeezebox Touch Streamer w/EDO applet
    iFi nano iDSD DAC
    iPurifier3
    iDefender w/ iPower PS
    Custom Steve Wilson 1m UPOCC Interconnect
    iFi Mercury 0.5m OFHC continuous cast copper USB cable
    Custom Ribbon Speaker Cables, 5ft long, 4N Copper, 14awg, ultra low inductance
    Custom Vibration Isolation Speaker Stands and Sub Platform
  • F1nut
    F1nut Posts: 49,711
    robosdad wrote: »
    Schurkey wrote: »
    The Polk SDA crossovers can be more-complex than what is used on other speakers]

    Doesn't matter. Process is the same, you may be working longer to get all the parts changed. Figure out what capacitors, resistors, and (maybe) inductors you want to replace, do one crossover at a time, and have fun.

    Rebuilding the crossovers on my 1Bs made them much more enjoyable.

    Awesome- thanks. I'll start researching it, but if you know of any good resources (especially ones written for a beginner) please let me know. At this point I don't even know what or where to order (for the Heresy's I bought a kit). Thanks!

    I strongly suggest you not follow what the plastic person did. Instead do a Google search for Polk SDA 1C crossover upgrades. Ignore the eBay ad for their upgrade. Read the links to the forum here. This is one example, https://forum.polkaudio.com/discussion/89067/sda-1c-crossover-upgrade-journey-begins
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