2 Subs, One amp, Best way to wire?

Discussion in 'OT Technology' started by couchlock, Apr 11, 2007.

  1. couchlock

    couchlock OT Supporter

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    So my buddy gave me a box w/ 2 subs and an amp on it to add to my exisiting system. All I did was Y-split off some RCA's from my speaker amp and run them into this new amp. I am wondering the best way to configure this setup


    I looked up the info on the amp powering the subs (2 JBL 12's), its a Kenwood KAC-729S
    http://www.crutchfield.com/S-zBPpok...p?print=Y&g=100&id=detailed_info&i=113KAC729S

    Currently, I have it with the LP filter on, Stereo mode, and Input Sens all the way down. It still gets pretty damn loud! I am trying to figure out the best way to tune this.

    It looks like my friend has both subs wired up to their own channel, Is there a reason to wire subs up like that? From what Ive gleaned from you guys I figure they should be in bridged mode if they are just going to providing lows anyway.

    What are your thoughts on this?
     
  2. Create

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    That particular amplifier will not be able to run both subs in bridged mode.

    If you run bridged, you have to wire the subs into series or parallel, giving a 8 ohm or 2 ohm load to the amplifier. While the amp would function with an 8 ohm load, you would get heavily reduced power. If you try it with a 2 ohm load you'l blow that pos kenwood amp in no time.

    You've almost got it correct.

    Each sub gets it's own channel on the amp.
    LP filter on and set to something between 80 Hz and 100Hz on each channel.
    Turn off 'stereo mode' to see if you can run both channels from a single RCA input.
    Check the 'input sens' setting using an online manual and adjust it accordingly. You want RCA-level input, not speaker-level.
     
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    If the subs are oddball 2 Ohm, or 4 Ohm dual voice coil, then it would work in bridged mode with this amp (with certain wiring). If the subs are 4 Ohm, single coil run them as above.
     
  4. couchlock

    couchlock OT Supporter

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    thanks man

    I think I am going to leave it how its setup now, I think when i turn on the LP it mixes the LC and the RC, therefore making it mono anyway, The CX doesnt seem to have adjustments for hz

    Ill fuck with the input sens tomorrow, it sounds pretty good at the lowest stock level

    I split to the Y before the amp, so they should be RCA-level inputs, Im using a OEM-1 adapter from my stock HU to give me 2 RCA pairs
     
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    See if you can daisy-chain the amps, meaning the output RAC of one amp feeds the input RCA of the next in the chain.

    Most amps run a static current on their RCA out's regardless of the input level. This means your signal arrives at both amps with full amp's and all wires run full amps. This makes the signal less prone to interference from the surroundings.

    This is fairly minor of it's radio shack style, but provides better SQ on the same cables.
     
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    Also note that your amp claims it's 2 Ohm stable if *not* bridged. You could run 4 subs, albeit subs with 75W reco RMS.
     
  7. couchlock

    couchlock OT Supporter

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    I dont think my amp has RCA outs
     

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