What is the purpose of two FireWire ports?

[euphoria89]

At title,

I dont understand why certain soundcards have two FireWire ports on them. My uncle has a MOTU 828 with two ports on it, but if i connect either of them up to the same PC (presumably for double the bandwidth), it doesnt function at all. Even if i connect it to two different computers at the same time, it doesnt function properly on one of the PC's.

Am i just not doing my research properly, because i cant really find much info on the net about this..

Regards.
Nathan.

[warmer]

a connect thru, although I wouldn't use this feature

[esaias]

First:
MOTU hardware is not FireWire, they use FW connector and hardware but they run their own propietary protocol so MOTU hardware is not meant to be used used with Firewire devices.

edit:

Oops, I was only thinking of MOTU's PCI Audio devices, the text above refers to them. MOTU has standard FW audio interfaces too.


But in general, you can daisy-chain firewire devices, therefore the 2 ports exists

like this: computer - Audiointerface - External HD

The connections you mentioned were exactly the wrong ones
(although you can connect computer to computer with firewire, and have a hub in between them atlhough I suspect that using a audiointterface as a hub between computer is nothing but trouble)

Do NOT make double wiring setups!

-Tomi

[euphoria89]

So what exactly would happen should i plug the extra firewire port from the rear of the 828 into his external hard drive? Would it duplicate the data stream from the soundcard - computer onto the external HDD?

[RockManDan]

no, you would still need software to decode teh data stream and load it into ram in order to save it to a wav or aiff or whatever. the daisy chaining simply allows for both to be accessed by the same computer. I have had problems doing this. i used to connect my mackie onyx mixer and my external hdd via firewire and i would get slower write speeds and such. now i connect my hd via USB 2.0 and the mixer via firewire and they dont bother each other.

but you can't go from the audio interface to the hd as the hdd has no software/cpu/brain of its own in order to decode the datastream and write it as a file.

[euphoria89]

Ah i see,

So basically its just like an Apple keyboard. It uses up one of your USB ports, so has another built into the side of it to make up for your loss of a single port.

I'm guessing with audio this is not recommended, due to the issues that could arrise?

[Jimbo]

Originally Posted by euphoria89

Ah i see,

So basically its just like an Apple keyboard. It uses up one of your USB ports, so has another built into the side of it to make up for your loss of a single port.

I'm guessing with audio this is not recommended, due to the issues that could arrise?

What issues?

I (and many others) do it all the time:
recording 16 tracks: macbookPro --fw-> mh2882-1 --fw-> mh2882-2 --fw-> externalDrive

I wouldn't try that with USB2, though. Firewire is a completely different beast.

Here's a quick read: HowStuffWorks "FireWire vs. USB"
The "Data Transfer Rate" table row is misleading. Those numbers refer to burst speed, NOT continuous transfer speed. Burst speed is better for USB2, but the continuous transfer rate (which we need for audio) is much better with FW.

[RockManDan]

yea like he said its entirely possible to daisy chain without any ill-effects...depends on your system. with a mac id bet you could do it all day and not have an issue. with me on my windows system, where IRQs are shared all over teh place and my FW mixer can't be used as teh same time as my wireless card, there are bound to be conflicts somewhere.

you'll never know if something works until you try it. something may work in theory but in practice who knows.

[esaias]

Remeber that when you are daisy-chaining, put the fastest (S800) first in chain and the slowest (S200) as last one.

Computer <-> FW S800 devices <-> FW S400 devices <-> FW S200 devices

therefore you have maximum bandwidth in use.

-tomi

[explorer]

I think that's wrong. If you plug a firewire 400 device into a firewire 800 port then all devices on that firewire bus are now running at 400.

[RARStudios]

wait so i can link my MOTU 896HD and my Edirol FA-66?


I just want the midi on the edirol.... =)

[FeatheredSerpent]

No, the drivers for the AI will determine what can be linked together, you won't be able to link 2 audio devices from 2 different manufacturers.

[RARStudios]

Hrm...is there any other kind of Midi attachment device i can use with my motu?

[WishingDigiJosh]

Originally Posted by explorer

I think that's wrong. If you plug a firewire 400 device into a firewire 800 port then all devices on that firewire bus are now running at 400.

Explorer is correct. All FireWire devices on the same bus will switch to the lowest common denominator. If you have, for example, 5 FW800 devices and 1 FW400 device, they will ALL run at FW400 regardless of the order of the chain. Bummer eh?

[travisbrown]

Originally Posted by FeatheredSerpent

No, the drivers for the AI will determine what can be linked together, you won't be able to link 2 audio devices from 2 different manufacturers.

That's funny, because I usually have an 828MKII, Presonus Firestudio Lightpipe, ART TubeFire8 and a couple drives chained to each other with no problem.

Unless you mean that you can only use one device at a time. I think this is the case with ASIO drivers; however, on Mac Digital Performer and others can run multiple drivers for multiple devices, and also you can create aggregate devices on Mac. I'm sure there must be a way to do this on PC too.