In line capacitor for cutting out lower frequencys'?

Discussion in 'Archived Threads 2001-2004' started by Ron-P, Mar 8, 2002.

  1. Ron-P

    Ron-P Producer

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    I have a pair of Polk Audio RT25i's as my surrounds. The frequency range is 50Hz - 26kHz. I prefer them set to large, along with the rest of my speakers. Problem is, I do not want to damage them with the full frequency range being fed in.
    Is it possible to insert a capacitor inline between the speaker and receiver that will cut out the low end frequency just above the 50Hz, say around 60Hz or so and doing this without effecting sound quality?
    My Marantz SR5000 does not have individual speaker bass controls and I believe setting the speakers to small cuts everything off at 100Hz, way to high.
    Peace Out~[​IMG]
     
  2. Ron Shaw

    Ron Shaw Stunt Coordinator

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    Yes, it is possible, but the values will be large. For an 8 ohm speaker, you will need about 330uF for -3db at 60Hz. 400uF for -3db at 50Hz. Film caps are best, but it will be pricy to use all film caps. You can use several, wired in parallel. It would be cheaper to use, say, a bipolar electrolytic of about 300uF, with the rest made up of film caps. A better solution, is a small film cap at the input of your amplifier section. The value would depend on the input impedence of your amp. If you dont know what it is, just try putting a small cap (maybe .01uF) in series with the input, and measure the response at the output to determine the -3db point. This would take a signal generator and a meter or scope, but would be the best way.
     
  3. Ron-P

    Ron-P Producer

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    Woah, Fly by.
    Thanks Ron, although most of that went over my head. My local electronic shop said I can use something called a "bass blocker". It goes inline and stops anything below the chosen Hz from hitting the speaker. They run about $6.00 each. Have you heard of these?
    Peace Out~[​IMG]
     

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