Sub speaker level connections

I'm looking for a sub and need these connections. I've seen some subs with just the input connections and other with both the input connections and also output. Why would you use both?
Yep, my name really is Bob.
Parasound HCA1500A(indoor sound) and HCA1000(outdoor sound), Dynaco PAS4, Denon DP1200 w/Shure V15 Type V and Jico SAS stylus, Marantz UD7007, modded Polk SDA 2B, Rythmik L12 sub.

Comments

  • msg
    msg Posts: 9,306
    I think it's just to go back out to the speakers from the sub. Not 100% on whether the output signal will only be high-pass, though. That part may vary by manufacturer?
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  • rooftop59
    rooftop59 Posts: 7,952
    muncybob wrote: »
    I'm looking for a sub and need these connections. I've seen some subs with just the input connections and other with both the input connections and also output. Why would you use both?

    Yes some like the Martin Logan dynamo have a built in high pass at 70hz (a few have an adjustable high pass) when using either the speaker level or line level outputs. Allows you to take some strain off smaller bookies. Input on that one is variable crossover iirc...
    Living Room 2.2: Usher BE-718 "tiny dancers"; Dual DIY Dayton audio RSS210HF-4 Subs with Dayton SPA-250 amps; Arcam SA30; Musical Fidelity A308; Sony UBP-x1000es; Squeezebox Touch with Bolder Power Supply
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  • msg
    msg Posts: 9,306
    Crossover slope is also something I've been curious about for blending, but I'm not sure I've seen that specced in any manuals I've read so far.

    One of the things I read about in MartinLogan documentation was to set the sub's crossover at 70% of the speaker's low frequency output spec as a starting point. I've tried this and found it to be a good starting point for blending the sub.

    Prior to reading this, I'd typically set the sub's crossover right at the speaker's low frequency output spec. Seems to depend on the sub, speakers, room, etc., but that 70% recommendation from ML must take into account the crossover slope? I would think that it is more gradual vs a steep drop-off? Anyone else have any experience here?
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  • pearsall001
    pearsall001 Posts: 4,981
    muncybob wrote: »
    I'm looking for a sub and need these connections. I've seen some subs with just the input connections and other with both the input connections and also output. Why would you use both?

    The output can be used to daisy chain another sub
    "2 Channel & 11.2 HT "Two Channel:Magnepan LRSSchiit Audio Freya S - SS preConsonance Ref 50 - Tube preParasound HALO A21+ 2 channel ampBluesound NODE 2i streameriFi NEO iDSD DAC Oppo BDP-93KEF KC62 sub Home Theater:Full blown 11.2 set up.
  • vmaxer
    vmaxer Posts: 5,116
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  • muncybob
    muncybob Posts: 2,961
    Yea, I saw those. A bit far for me.
    Yep, my name really is Bob.
    Parasound HCA1500A(indoor sound) and HCA1000(outdoor sound), Dynaco PAS4, Denon DP1200 w/Shure V15 Type V and Jico SAS stylus, Marantz UD7007, modded Polk SDA 2B, Rythmik L12 sub.