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Some help using (sound) capacitors

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JRP
  • Member since
    November 2006
  • From: Upland, CA
  • 301 posts
Some help using (sound) capacitors
Posted by JRP on Sunday, October 4, 2009 11:16 PM
I'm installing a Soundtrax DSD-AT100LC along with an 8 Ohm speaker. It came with a capacitor. I know that I need to connect the capacitor in series with the speaker, but what I don't know is which wire end of the capacitor is positive or negative. One wire leading out of the capacitor is longer than the other. Where do I need to install each purple wire and does it make a difference? If I wire them wrong, will I blow the speaker? Is it better to solder one end of the capacitor wire to one of the speaker connections directly or use the purple wires inbetween? Thanks JRP
  • Member since
    October 2004
  • From: Colorful Colorado
  • 8,639 posts
Posted by Texas Zepher on Sunday, October 4, 2009 11:40 PM

JRP
what I don't know is which wire end of the capacitor is positive or negative.

By convention the long lead is the cathode (+)

Where do I need to install each purple wire and does it make a difference?

The short answer is no.  They are both purple because the power to the speaker is basically AC, and it doesn't matter.  The only difference is whether the speaker pushes out or in with a positive pulse. If one wants  the polarity of the capacitor could be matched with the polarity of the speaker, but I've tried it both ways and cannot tell the difference.

If I wire them wrong, will I blow the speaker?

No.  Well, no if wired one way or the other with the two purple wires.  If wired wrong with one of the other colored wires it could blow the speaker or the decoder.

Is it better to solder one end of the capacitor wire to one of the speaker connections directly or use the purple wires inbetween?

Irrelevant, it doesn't matter at all.

  • Member since
    October 2006
  • From: Western, MA
  • 8,571 posts
Posted by richg1998 on Monday, October 5, 2009 1:14 AM

It does not matter. The instruction card that comes with the decoder clearly shows how to connect the capacitor/speaker/wiring. I have used the DSD-100LC decoders.

If you ever use the Tsunami decoder, it to comes with a capacitor but is Not for sound. Again, the instructions will be very clear.

Rich

If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.

  • Member since
    July 2003
  • From: Sierra Vista, Arizona
  • 13,757 posts
Posted by cacole on Wednesday, October 7, 2009 9:11 AM

 The capacitor supplied with the LC decoders is a non-polarized type, so it doesn't matter at all which wire it is inserted into.  The capacitor has no positive or negative side.

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