What makes you think you would have to buy an HD core card? That's for Pro Tools. An HD core card has nothing to do with a Rosetta.

The Rosetta 800 has 8 channels. You can't get anymore out of it than that. The sampling rate will not effect how many channels you have.

192 is not even supported with apple computers. This seems weird

Why are you concerned with 192? It would be a waste to even use 192 anyways.

If you want 16 i/o look at the Apogee ADX 16 and the DAX 16.

because the firewire adapter is not available yet, only the HD card, which you would need a Digidesign HD core card. And I was talking about getting multiple rosettas.
http://www.apogeedigital.com/pdf/xfirewire_technote.pdf
unless I am reading wrong, that tells me that the only way I can use multiple rosettas to achieve 16 bidirectional channels is by only using 44.1-48
is it a waste to use 192??? Not from what I've benn leraning. To each their own, I think. But do you even own a rosetta? What do you use?

Looking at your link, I'm going to assume that you are mixing up ProTools HD Core card with Apple Core Audio drivers.
They are different, right?

because the firewire adapter is not available yet, only the HD card, which you would need a Digidesign HD core card. And I was talking about getting multiple rosettas.
http://www.apogeedigital.com/pdf/xfirewire_technote.pdf
unless I am reading wrong, that tells me that the only way I can use multiple rosettas to achieve 16 bidirectional channels is by only using 44.1-48

That's the only way to use multiple Rosettas with Firewire. Firewire and HD aren't your only options. Which MOTU's do you have? You can use the Rosettas with 2408's for up to 96 channels of I/O, depending on which version you have...if you have the MkII version, you can do 48 channels at 96 kHz. There are also other options from companies like RME and Lynx that don't require any optional cards from Apogee that would be the way to go if you want to use multiple interfaces.

is it a waste to use 192??? Not from what I've benn leraning.

Actually, Apogee will be the first ones to tell you that their converters sound just as good at 44.1 kHz as they do at 96 kHz. You won't read it in their ads, of course, but if you talk to them at a trade show they'll tell you that, and I've seen them mention it on forums as well. There's no reason why a converter can't sound as good at lower sampling rates as it can at higher rates.

-Duardo

I have 2 1224's and I upgraded to the pc424 card. You mean to tell me I can use the rosettas w/ the card?

Not directly...but you could add a 2408I/O and go in that way. Probably cheaper than going with the Firewire cards if you're looking at more than one, and definitely cheaper than an HD card.

-Duardo