sda

seth purvin
seth purvin Posts: 6
edited August 2008 in Vintage Speakers
please help my SDA1A


Hi all I have a few questions about my SDA1a. (They are 2 inline vertical tweeters, over 4 midrange, over 1 radiator vinyl wood cabinets) I bought them new back in 1986 I have done nothing to them at all. Now that I find myself getting back into vinyl I’m thinking they might need some TLC.

I’m running a B&K st140amp and a pro 5 pre amp
At what most would consider normal volume and appropriate music they are flawless.

At LOUD volume these are my problems
First problem is that at loud volume the tweeters cut out but will rest themselves over time.
Second at loud volume with newer music the radiators pop hard and must be turned down.
Are there any upgrades that can be made? I’m more of the swap stuff out kind of guy not the soldering gun type.
Also were can I get these replacement parts and I’m thinking of selling them what is a good price
Thank you all
Post edited by seth purvin on

Comments

  • ben62670
    ben62670 Posts: 15,969
    edited August 2008
    Well welcome back. Tweeter problem is you might have bad Poly Switches. These go bad over time,but... This is a big butt. You also complain about your PR's popping. It sounds like you have the bass, and treble turned up. It should be set to flat at high volumes, and no more than +2db.
    Ben
    Please. Please contact me a ben62670 @ yahoo.com. Make sure to include who you are, and you are from Polk so I don't delete your email. Also I am now physically unable to work on any projects. If you need help let these guys know. There are many people who will help if you let them know where you are.
    Thanks
    Ben
  • candyliquor35m
    candyliquor35m Posts: 2,267
    edited August 2008
    I used to have both those problems with my sda 2b's when I would drive them hard.

    Now that I keep my volume at 12 o'clock or lower and no longer have those problems.

    Your tweeters and drivers are fine and don't need replacing.
  • BSUfbfan
    BSUfbfan Posts: 201
    edited August 2008
    Before you take candylickers advice to heart, where is your volume control when you say the music is "loud"? If it is below 12 o'clock, then you may indeed have 2 problems... first, as Ben mentioned, it is very possible that the old original polyswitches (tweeter protection device) are bad and need to be replaced.... second, if you are getting a popping sound from the woofers, you may have a bad 6" driver (it isn't the radiator popping, as it is a passive device). With the speakers turned off, gently push on all of the 6" drivers and see if any of them make a metal-on-metal rubbing sound. If so, order a replacement driver.
    SDA SRS 2.3
  • leroyjr1
    leroyjr1 Posts: 8,785
    edited August 2008
    This sounds like a quick fix. Just sell them to me.
  • F1nut
    F1nut Posts: 50,735
    edited August 2008
    As stated, it could be one or more of the mid-drivers bottoming out, but it could also be a PR that has separated the front section from the rear. Pull them out, if there's a problem you'll see it easily enough.
    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

  • seth purvin
    seth purvin Posts: 6
    edited August 2008
    ill gladly sell them for 350