Testing a subwoofer amp...

Discussion in 'Archived Threads 2001-2004' started by DaveVan, Jan 27, 2003.

  1. DaveVan

    DaveVan Extra

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    My RCA RT2500 receiver has a builtin amp for the passive sub. I would like to know if the output is already low-pass filtered, or if the crossover is built into the passive sub enclosure.
    Im thinking I can just connect one of my bookshelf speakers (100w,6 Ohm) to the amplified sub output (200w into 3 Ohm).
    If I hear nothing from the tweeter, then the sub output would be filtered, correct? Would this possibly damage my speaker or amp?
     
  2. Ryan Schnacke

    Ryan Schnacke Supporting Actor

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    Yeah, that's probably the right method. You might also try fiddling with the speaker settings - small vs large. Or maybe try inputting a full-range signal into the subwoofer input of the 5.1 channel inputs.

    It sure would be silly to leave out the low-pass filter on something like this. But its impressive that the sub out has a performance rating at 3 Ohms. This would seem to indicate 3-ohm stable operation. Then again, I've got a cheap Pioneer stereo receiver that rates "Dynamic Power" down to 2 ohms but says to use 8 ohm speakers. I wouldn't dare try it into 2 ohms.
     
  3. Andrew Pierce

    Andrew Pierce Stunt Coordinator

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    What a weird receiver. I wonder if the sub amp is any different from the other channels. Assuming the power supply can hack it, isn't 200W @ 3 ohm about equal to 100W @ 6 ohm, or 70-80W @ the 8 ohm that everyone else rates their equiptment at? Of course, I wouldn't assume the power supply could deliver that to more than one channel at a time...
     
  4. DaveVan

    DaveVan Extra

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    Thanks guys [​IMG]
    Tried it out and it does seem to be low-pass filtered in some way. I was pleasantly surprised by the bass output of my bookshelf speakers too.
    And thanks to the thread on test tones, I can burn a test cd to see what the corner frequency is on the output.
    So it seems to build a sub, all I need is a decent driver in a sturdy box, no electronics needed. It may not be the best way, but my funds are very limited.
     

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