Another point worth clarifying (and I’m note going to, cause I’m not sure) is the difference between multiple connections on the CPU/Laptop versus how many actual ports are available.  Sometimes the I/O chip on the motherboard is already chaining multiple connectors into a single logical port.

And then there’s the lowest common denominator: the slowest speed in the chain sets the speed for the chain.  I understand putting a 400 in front of an 800 drops them both to 400, but its not clear that putting the 800 first makes a difference with some devices. And if you have two connections, one 800 and one 400 fed by the same logical port, what then?

Having a 400 device on the chain slows the whole chain, and any other ports off the same chip on the motherboard, to 400. No mater where in the chain it is.

I believe USB works the same way, yes?

<L>

Oh, and I use an 002, and drives work just fine coming after the 002. It only puts data in danger if you turn off the 002, which I never do… But it is god practice to put the drives first. I only use downstream drives for transfer, not routine storage, as it is easier to acces the port on the 002 than on the back of my Mac…

Lou

OK, so, I have an Imac i5 27”, a “mybook 500gig” drive on a single FW800 output to 400FW cable, then to a Presonus Lightpipe 24ch interface and that should work?

Worthy points made by all. As Lou mentioned, a Firewire 400 device inserted anywhere within the Firewire 800 chain will immediately drop the entire Firewire 800 bus speed to the theoretical maximum of a Firewire 400 bus. However, if your computer has a Firewire 400 and 800 bus, using a Firewire 400 device on the Firewire 400 bus will not affect the speed of the Firewire 800 bus, even if both busses share a chipset.

This actually works slightly differently from the USB spec, in that using a USB 1.1 device on a USB 2.0 bus will obviously only run at USB 1.1 speed. However, if using a USB hub, other USB 2.0 devices will continue to run at high speed using a transaction translator to create a virtual full-speed bus.

Brian, in response to your question, I would hook up your system as follows: iMac -> MyBook 500 -> Presonus FireStudio. As Lou mentions, generally it’s only your data which is in danger if your drive is placed after the interface (incase the interface is turned off). However, as your track count increases with firewire interfaces, I’ve found I can achieve lower latency and higher track counts when configured computer -> drive -> interface, instead of computer -> interface -> drive.

For some reason I have two email notices of replies, but don’t see those replis on the web page - maybe it takes a wile to update???

In any event, thanks for the clarifcation on the USB chain. I don’t use it for audio anyway, but good to know!

<L>

Glad I could be of help, Lou.

Thank you.

I was hoping to also address a compatibility question regarding the FW port on the mac rendering the individual outputs and inputs inoperative, a rumor that the hierarchy of connectivity might re-enable them, so that I don’t have to send my entire new system back to the dealer.

Any help there?

Brian, your question makes no sense to me - what is the problem?

WHAT individual I/O are you talking about? what is “the Hierarchy of Connectivity”? Sounds like a mystical cult!

L

Hi Lou,

Thanks for asking,

My “chain” is a Presonus Firestudio Lightpipe, a “MyBook 500Gig” drive and a Mac i5.

I have been told that the reason my imac will not properly recognize the Presonus unit and won’t communicate with it properly to have all the inputs and outputs work “properly” is because the imac has changed the firewire chip set to one that does not work with almost any device other than a drive.

I have also been told that “maybe” changing the hierarchy, or order of connections will alleviate this BUT it has not been proven or backed up by anyone considered “knowledgable”. I’d like to get some backup for that before I jump through several more hoops.

So, the problem is all your I/O don’t work? You aren’t really stating the problem. And what DAW software is another important item, as well as the OS, though you are probable using snow leopard, and I only use Protools and OS 10.4.11 Tiger.

But it is dirt simple to try it both ways and see what happens.

MY brain trust for Mac DAW help is the Daw-Mac yahoo group. In 12 years I have learned more there than anywhere else.

Brian,

As you mentioned, Apple has indeed changed their Firewire chipset in some models to the LSI/Agere FireWire chip-set with which many have seen with whom, including audio interface stalwart RME where the issues has been extensively documented in their forum. There has been a great deal of discussion in the RME forum which ended in a conclusion that when using Mac’s containing the LSI/Agere chipset their audio devices only work when a FireWire drive is placed between the audio interface and the computer. It’s an odd problem, but I can honestly say that you wouldn’t be the first. While I can’t confirm that your computer has this chipset, all the information you need is contained in these lengthy forum posts: http://bit.ly/MacFW and http://bit.ly/MacFW2  and http://bit.ly/MacFW3

As Lou stated, when I’m presented with a situation like this, it’s always best to try every option, document what works and what didn’t, and then solve any remaining issues. Also, I too can vouch for the quality of information held in DAW-Mac, as well as in our very own REP Forum.

Kyle

Exactly! haha. I HAD 10.4.11 and PT working for years, but, that computer went up in smoke, literally, so, I had to buy a new one. REGRETTING IT. Thought I’d move to Logic Pro 9, and Snow Leopard, Logic works great, not much learning curve, but, the computer will not realize the Presonus unit and wouldn’t even recognize an M-Audio Profire Lightbridge.

I’ll follow your suggestion and head over there, thanks again.

Thanks Kyle, I’ll head on over, and I agree and second your vouch for the forums. I’ll give it a try.

Thanks from me too Kyle! I am firmly three to five years behind the bleeding edge, and keep learning from people who can afford new Macs! And my sympathy, Brian. My G5 is still smokin as distinct from smoked… I drea the day I have to dwal with Intel macs, though their owners seem to love them. I have simple needs, and a low budget… Still have working 9500 and G4, just they can;‘t run newer bloated OS and sfotware.

Lou