This may be a noob question but when exporting clips out of Pro Tools, say with fades and what not, does anyone know if the sound card is engaged at all? The reason I ask is I have some sounds I've recorded using some pretty high-end conversion via firewire and I don't want those sounds degraded if I do some editing to the files when not hooked up to the firewire sound card and just editing on my laptop, and then exporting the clips/regions out. Hope that makes sense and isn't too ridiculous a question to ask. thanks.
In short, no. The sound card is only engaged in the listening back of the audio. The processing of the sound is purely mathematical and done by your DAW much like a calculator.
I guess what you're asking is whether audio passes through an A/D or D/A converter and conversion when it's exported from a software e.g. Pro Tools. No it doesn't, because it's digital while it's stored (it's an audio file) and handled by the computer (it can be opened and edited with software programs), so there's no need to convert it at all or convert it in other ways than digitally (which can only induce digital calculation errors, but is not related to the sound cards converters. Practically digital-to-digital conversion is "lossless", depending on whether you do something that you shouldn't or not).
On another note, whether the sound card is "engaged at all" or "reserved" depends on how Pro Tools handles the audio card. It's possible that it's reserved at all times when Pro Tools is open and disconnecting the card while Pro Tools is open may cause Pro Tools to throw an error or crash. Respectively, it's possible that Pro Tools chooses when it accesses the sound card and when it doesn't, but doesn't reserve it all the time while running.
You'll need a soundcard to work at 192kHz - Protools without any hardware will only run at 96kHz maximum (and obviously only some PT hardware options support 192kHz)