Help with new set of old speakers (RT5, CS200, CS225)

onree
onree Posts: 2
Hi Polk people -- I recently tried to upgrade my Onkyo HTiB with a set of Polk fronts off of Craigslist. What I got was: a pair of RT5s, and then a center channel CS225. Much to my dismay, I found that the center channel is very buzzy and pretty much unlistenable, and the original seller refuses to take it back. At least to my unrefined ears, the RT5s seem to sound okay.

So here is my question -- in researching the issue with the center channel, I found out that one way to test the woofer is to push around gently on the woofer cone, and see if it bumps into anything. On all three of the original speakers I bought -- both RT5s, and the CS225, the woofer cones seem to rub up against something when the cone is pushed in. And they all feel that way in the same place, at about 12:00. On the CS225, if I pushed in with a bit more force on the centers, it actually seemed to resolve the buzzing, at least for a short while before it gets bad again. Does this mean that all three of the speakers have damaged woofers? And is it remotely worth it to try to get anything fixed? (I paid $60 for all three speakers.)

I went back onto Craigslist (I know, I never learn) and got a CS200 for another $25, and at least on that speaker, the woofer cones do not seem to rub against anything when pushed in. Again, to my unrefined ears, when I listened to the output of the CS200 compared to the RT5s, it all pretty much sounded the same (aka "seems okay").

Thanks in advance for any advice anyone can provide.
Post edited by onree on

Comments

  • Eric W
    Eric W Posts: 556
    edited January 2009
    That's one way to test (the push the cone in method) but not the most reliable. If you aren't pushing directly center on the cone, it could pull the voice coil out of alignment and then you'll feel the rubbing and scraping- but based on what you describe it sounds like those cones are no good.

    If the speaker cone is frozen in place, it's definately toast.

    Another method (requires a bit more work, but is more reliable) is to unscrew the driver from the cabinet and unplug its wires. Then, pretend that component is it's own speaker and hook it up to your stereo. If it sounds horrible or has no sound, then that component is no good.
    -Eric
    -Polk Audio
  • onree
    onree Posts: 2
    edited January 2009
    Hi Eric -- thanks for the reply. So are you saying that instead of pushing along the edges of the woofer, I should push straight in from the center? And what do you mean by "frozen in place"?
  • Eric W
    Eric W Posts: 556
    edited January 2009
    Yes, or try applying equal pressure to 2 opposite areas of the cone to give the most even pressure possible (not to mention most of our cones have a soft dust cap in the center of the driver).

    Frozen in place = cone doesn't move at all when you try to push in on it.
    -Eric
    -Polk Audio
  • pw525it
    pw525it Posts: 2
    edited July 2009
    Hi All,

    I'm having the same issue, intense distortion on center channel. I've owned the set (RT12, CS225, & M series rear) since new, +/-14 yrs, and they've always performed and have never been run hard. So now the question is 1) Why did this happen? 2) How do I fix it (cheaply)? 3) How do I prevent it from happening again?

    Thanks in advance for you help/advise.
  • pw525it
    pw525it Posts: 2
    edited July 2009
  • apphd
    apphd Posts: 1,514
    edited July 2009
    pw525it wrote: »
    Hi All,

    I'm having the same issue, intense distortion on center channel. I've owned the set (RT12, CS225, & M series rear) since new, +/-14 yrs, and they've always performed and have never been run hard. So now the question is 1) Why did this happen? 2) How do I fix it (cheaply)? 3) How do I prevent it from happening again?

    Thanks in advance for you help/advise.

    Sorry can't help with #1 and #3, but you should try posting this in the "troubleshooting" section. As far as #2 contact Polk CS. Tell them you are a CP member, as I think they still over a discount for members.
    Good luck and welcome to CP.
  • AVT
    AVT Posts: 4
    edited July 2014
    could be crossover network (capicator,resistor,inducter coil) inside cabinet. Like someone said pull the woofer out and hook it up direct to amp just to see but dont turn it up real loud