LX81 Bi-Amping front speakers how?

Discussion in 'AV Receivers & Amplifiers' started by Showoff, Jan 31, 2009.

  1. Showoff

    Showoff
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    I posted this in the general LX81 thread, but thought it better to have it own...

    I'm going to Bi-Amp my GR60's which have 6 terminals, the bottom two on the GR60's I have connected to the front terminals on the LX81, the next terminals up on each side I have bridged (see pic) and planned to connect these to the surround left and rights, however the manual talks about using the surround backs for Bi-Amping and has settings in the OSD to set this? I don't yet have any rear speakers, but would use the surround backs for these and surely the surround channel (sides) for Bi-Amping? Have I got this all wrong?

    Please help.

    Thanks.
    [​IMG]
     
  2. Danepack

    Danepack
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    use the surround back input for bi-amp as it says in manuel.
    if you get surround speakers, use surround input for those.
     
  3. Showoff

    Showoff
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    So use the surround channel for rears? don't they get a different signal?
    Surely it would make more sense for the amp to be set up so that the surrounds (sides) can be used for bi-amp as 99.9% of people would have a 5.1 set up with fronts, a centre and rears not fronts, a centre and sides?

    Sorry if this is a stupid question I'm still learning.

    Thanks,
     
  4. Gadgetcity

    Gadgetcity
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    No such thing as a stupid question. You want to get it right when you are messing about with expensive equipment!

    Danepack is right...

    Most people have 5.1 as you say which uses centre, front and surround.

    7.1 adds in "surround back" speakers. As most people don't use these the Amp allows you to reassign them as a second amp for the front speakers for bi-amping the front speakers.

    As an aside - on some amps the surround back can also be assigned as a second room or as front "presence" speakers or as a rear centre speaker.

    Hope that helps
     
  5. Showoff

    Showoff
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    That does help thank you.
    I think what is confusing me is I assumed that for 5.1 the two rear speakers are the backs or surround backs and surrounds are for sides or for 7.1 which are the ones most people don't use, does that make sense?

    One last questions for tonight at least, I have connected the bottom (low) terminal on the GR60's to the front channel of the amp and bridged the other 2 terminals on each side which are now connected to the surround backs, according to the manual for bi-amping they have the high frequencies (ie the upper terminals on the speakers) connected to the front channel and the lows connected to the surround backs? Is this correct as the guy in the shop said the other way around? Does it matter?

    Thanks again
     
  6. Jimmo 32

    Jimmo 32
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    No it doesnt matter,but what does is that you DONT use bridging wires/strips,while you are bi-amping.
     
  7. Dankeech

    Dankeech
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    Ok, think I'd like to make things a little clearer just to be on the safe side.

    Bog-standard speakers would have one set of terminals, + and - .
    Bi-ampable speakers have two sets of those terminals.
    Tri-ampable speakersd have three sets.

    Each set of terminals needs a connection to the amplifier somehow, either by a set of wires from amp, or being connected to another set of terminals on the speakers, effectively indirect connection to the amp.

    To single amp your speakers:
    Connect one cable - connect the positive and negative to the matching terminals on the amp, normally out of habit to the bottom set of terminals. The sets above are connected by wire to the bottom set, so all terminals have power.

    To bi-amp your speakers:
    Connect two cables, positives and negatives accordingly, recommend using the bottom set of terminals for the front channel outputs, and the other cable to the middle set of terminals, then connect the top set of terminals to the middle ones by wire or official link.

    To Tri-amp your speakers, each terminal gets it's own cable, 3 cables, 6 total connections.

    Edit: Here's a little diagram I made for your best wiring setup:
    [​IMG]

    Dan.
     
    Last edited: Feb 9, 2009
  8. cmcdonnell

    cmcdonnell
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    Is was wondering if this worth doing? are the SBR and SBL amps the same as the FL and FR? has anyone noticed much of a difference?
     

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