Mixing (chaining) Firewire 800 & 400 & its effect on speed

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Level 2

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Mixing (chaining) Firewire 800 & 400 & its effect on speed

Belkin makes a backward compatible Firewire 800/400 cable. If I chain 400 & 800 drives can I maximize speed by the order that I chain these drives. For example, if I place the Firewire 400 at the end and connect that to a Firewire 800 drive and then connect that to a Firewire 800 port on the computer will the 800 drives throughput be dumbed down to the 400 speed when accessing files on the 800 drive?

2.16 GHz Intel Core Duo, Mac OS X (10.5), 2 GB

Posted on Apr 22, 2008 5:59 PM

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Answer 1

Apr 23, 2008 1:54 AM in response to Michael Teel

I don't know for certain but I have heard that when you mix FW speeds on the same bus you get the slower one.

However, why are you worried about it, as FW400 is more than enough for any video uses?

Message was edited by: Ian R. Brown

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Answer 2

Silal

Level 5

6,461 points

Apr 23, 2008 7:54 AM in response to Ian R. Brown

as FW400 is more than enough for any video uses?

Not at all. It's fine for DV and formats with similar bitrates (I think HDV has the same bitrate). But if you need to edit a multiclip with several DV streams, you'll find some real time playback problems through FW400.

Hope that helps !

Alberto

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Answer 3

MartinR

Level 7

24,456 points

Apr 23, 2008 9:27 AM in response to Michael Teel

The entire Firewire bus is limited by the speed of the slowest connected interface. The 'conversion cable' will not make any difference, nor will the way you daisy-chain the drives. If you connect a FW400 drive to a FW800 drive and/or a FW800 port, you will be limited to FW400 speed on all connected devices.

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Answer 4

MartinR

Level 7

24,456 points

Apr 23, 2008 9:29 AM in response to Silal

For what it's worth, I've had as many as 4 stacked DV clips and never had a problem editing them off a single FW400 drive. Don't know if you have pushed it any further than that, but in my experience there's plenty of bandwidth on FW400 for editing DV and even HDV.

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Answer 5

Silal

Level 5

6,461 points

Apr 23, 2008 9:33 AM in response to MartinR

Martin

I found "the limit" myself editing a video clip we shooted using 9 takes. I had to move my captured media to a second internal SATA drive to get realtime playback.

It seems the limit is in a place between 4 and 9 streams! ;D

Alberto

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