Firewire port, should there be 2?

Discussion in 'AV Receivers' started by Brian Fitterman, Aug 12, 2003.

  1. Brian Fitterman

    Brian Fitterman Stunt Coordinator

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    Last night I was thinking about the future use of the firewire port on all of the new Processors comming out now. If I recall, not only can these be used for audio, but video as well. And if people can get their act together and form a standard (Mitsubishi tried) they can be chained together like SCSI devices on a computer. (an in and an out)

    We only have 1 input firewire input on our new units (all brands) If they do set a standard for video transmission on firewire, how would our units send it out? Convert it and out the component video? Or at that point we are done? For audio input, it is pretty straight foward, but if video is on the same signal, what happens to it?

    This is pretty much speculation on the future, that just may never happen, or if it does, it most likely will not be for years. But, I was curious non the less.
     
  2. JamesHl

    JamesHl Supporting Actor

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    It's not something that would affect current receivers. It seems like the standard for video in the future is going to be either dvi, or that multipurpose thing whose acronym escapes me at the moment.
     
  3. Rick Ewing

    Rick Ewing Agent

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    Firewire/i.Link/IEEE-1394 is a transmission standard that uses a bus topology for communications. Think of it as like Ethernet, except a lot more intelligent. For example, Firewire devices identify themselves on the network when attached and can specifically ask for a certain amount of bandwidth for the transmission (isonchronus communication). If the bandwidth is not available, then the transmission will fail, which is a good thing if you are trying to ensure that frames per second for video or audio doesn't drop below acceptable levels.

    Since Firewire is a bus, there are Firewire hubs available that you can buy now. The same ones sold by computer stores like CompUSA will work in a AV environment. So if you need more ports on your Firewire bus, you can always buy a hub and add as many as you need. Also, standards for transmission of audio and video with encryption have already been established...it's up to the manufacturers to support them.
     
  4. AustinKW

    AustinKW Stunt Coordinator

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    Brian,

    The firewire on upcoming processors is for audio only. Video firewire is dead, supplanted by DVI which is in the process of morphing into HDMI. The evolution of processors over the next couple years will be:

    1) equipped with 1394 iLink for hirez audio (SACD/DVD-A) still with component video switching

    2) 1394 iLink with DVI/HDCP video switching

    3) 1394 iLink with HDMI video/(audio) switching

    4) possible demise of iLink in favor of HDMI only

    Hope this helps.

    Austin
     
  5. DanielSmi

    DanielSmi Second Unit

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    Rick you will never need firewire hubs because each component comes with 2 bidirectional i.Link ports. So for example if you have the 49TXi you can connect the 47ai to it then connect the Sony XA-9000ES to the open port on the 47ai and then connect the Denon AX-11 (DVD-5900) to the open port to the Sony SACD player and so on. Since the have two ports they can be daisy chained and all of the components don't have to be on to transmit audio from the Denon to the 49TXi this depends on the component but the capability is there.

    Daniel Smith
     
  6. Brian Fitterman

    Brian Fitterman Stunt Coordinator

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    That was the piece of the puzzle I was missing. The componenets have the in and out. The processor is the last in the chain.
     
  7. DanielSmi

    DanielSmi Second Unit

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    Not really Brian the processor can be whever you want it in the chain. The ports aren't necesarily in and out they're bi-directional so you can have two outputs or two inputs there's no defined in and out. one thing you can't do is make a loop like run i.link from the 47ai to the 49TXi and then a cable from the 49TXi back to the 47ai.

    Daniel Smith
     
  8. Nick V

    Nick V Second Unit

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    What would the benefit of that be?
     
  9. DanielSmi

    DanielSmi Second Unit

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    What would the benefit of what be? I don't know what you're asking.

    Daniel Smith
     
  10. Nick V

    Nick V Second Unit

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  11. John Kotches

    John Kotches Cinematographer

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    You don't need to daisy chain, though. You can just as easily use a firewrire hub to do the connecting of multiple units.

    I don't know enough about Firewire topology to know what occurs when a device in the middle of the daisy chain is powered off. If the ports still had power, they could bridge the component that's "out of service", but don't know for sure that occurs.

    Regards,
     
  12. DanielSmi

    DanielSmi Second Unit

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    Sorry I took so long to reply I forgot about this thread. Anyways there would be no benefit for running a loop. The Ref 50 and TGPIII don't support that tranfer of audio through i.Link they just coincedentally have an i.Link on the port for a different reason. John the component has the capability to transmit the audio if in standby mode but it's say unplugged than it can't but some companies may coose not to implement this feature I believe the 47ai has this option. Another thing you can't do is apply jitter reduction technology. For example the 47ai if powered on can't take audio streaming to it from say the Denon 5900 bufer it and reclock it and transmit it to the 49TXi and since the 47ai and 49TXi have a non proprietary jitter reduction technology (it takes two components for jitter technology to work) they can talk to each other so that they can control the transmission speed of the audio and therefore eliminate jitter. The 5900 has a similar technology but it's proprietary.

    Daniel Smith
     
  13. John Kotches

    John Kotches Cinematographer

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    Daniel,

    Thanks. I spend too much time thinking about Ethernet and Fibre Channel. Firewire isn't fast enough to interest me professionally [​IMG]

    Regards,
     

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