5.1 through only 2 channels ?

Discussion in 'Home Theater & Video' started by SX550, Aug 9, 2018.

  1. SX550

    SX550 Well-Known Member

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    836
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    Looking across my favorite website I ran across some cheap ad for a bose lifestyle 12 and didn't knew anything about the lifestyles and have no need for one so but i noticed they only have L and R rca inputs...

    Can someone explain me how in the world do you connect a 5.1 setup using only 2 RCA cables ?
    There are no 5 channels ... only 2.
    This baffles me or i am an idiot.

    You'd need a spdif or coaxial for multiple channels ...

    [​IMG]
     

     

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  2. spark1

    spark1 Super Member

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    There is a surround decoder in the bass module.
     
  3. SX550

    SX550 Well-Known Member

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    Thank you.
     
  4. Silentnet

    Silentnet AK Subscriber Subscriber

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    Same way they got 4 channels out of quadrophonic records via 2 RCA. ;)
     
  5. SX550

    SX550 Well-Known Member

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    wow some guy just bid 200 on this yellowed 20 year old bose set.
     
  6. lbls1

    lbls1 Active Member

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    If there are no 5 separate channels then it isn't a 5.1. You may want to check to see if there are provisions for Bluetooth connectivity to speakers. Aside from this, the 5.1 claim is misleading.
     

     

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  7. charles 1973

    charles 1973 Super Member

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    It is most likely Dolby Pro Logic ll. In which case a center channel and two rear channels of sound has been encoded into 2 stereo channels. The .1 is the sub.

    This type of matrix decoding can be quite effective, Much more than simple matrix decoding that has not been encoded for surround sound and a huge step forward from stereo at its best. But of course not up to DD 5.1 standard

    So there are 5.1 channels of distinct sound, with 2 discreet and 3 matrix encoded and a sub.DD 5.1 has 6 distinct channels all of which are discreet.
     
    Last edited: Aug 10, 2018
  8. Duane

    Duane AK Member Subscriber

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    Yeah, a lot of people just assume 5.1 is a surround designation, where it actually is discreet individual channels via a digital source. Surround sound from an analog stereo source was called different things, but when Dolby introduced Dolby Surround, that became somewhat the standard. Dolby Surround and the subsequent Dolby Pro-Logic decoding was 3 front channels (left,center and right) a mono rear and a sub. On some decoders it would be displayed as 3/2. When Dolby Digital and DTS came along, they became the 5.1 generic designation.
     
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  9. lbls1

    lbls1 Active Member

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    447
    Yes, also add to this. You can have 5, 7, 9, infinity of channels, but in reality it is all based on the standard left, right two channel stereo configuration. Multiple channels are good for getting more sound power out to the stage, but it is still based on the old formula. So make sure that you are getting a high quality AV or multi channel amp, because if it sucks in the two channels, then you'll have a room full of noise instead of music.
     
  10. JoeESP9

    JoeESP9 ESL's & tubes since 83

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    Sorry, That's not totally correct. With Dolby Digital and DTS Digital it's possible to have surround sound or center channel sound with nothing coming from the front channels. It's not based on "the old formula". They are totally discrete channels. So is the .1 subwoofer channel.
     
  11. SX550

    SX550 Well-Known Member

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    The lifestyle systems are supposed to be surround sound ...

    Or do they just copy the front to rear channels and output the exact same sound ? hence there are only 2 rca cables going in from a source.
     
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  12. Silentnet

    Silentnet AK Subscriber Subscriber

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    No, they use an encoded surround signal. It's been explained in previous posts.
     
  13. lbls1

    lbls1 Active Member

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    447
    Im not sure what's being done, as I'm just coming onto this thread. It could be that only two channels are wired and their bridging extra speaker wires from them....its possible. But its not a true channeling. You need distinct right and left access from the amplifier in order to be classified as a channel.
     
  14. JoeESP9

    JoeESP9 ESL's & tubes since 83

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    Everyone else calls an encoded surround signal (Dolby Pro Logic for example) a matrix based system. That's all you'll ever get from an analog two channel stereo signal.
     

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