audio aifc files become mov files

My question - how can I edit a QT audio file and still save it as audio (as .aifc for example)? I've looked in Preferences, but can't see anything. "Save as" offers only the two .mov options.

Although your file is saved in a QT (.mov) file container, unless you have exported the audio to a different codec, it remains in its original format. (Check the "Get Movie Info" window to confirm this.) Since QT relies on the actual file content, this should not normally be a problem unless you plan to use the file with software that relies exclusively on the file extension for proper playback. In this case, simply highlight the file name extension and change it manually yourself. You will get a system warning message but you can override it by simply confirming your desire to make the change. The icon should then automatically change to match the new file extension.

However, when I imported the file into iTunes, it was described in "Kind" as a QT movie file, not an audio one, and did not play when loaded onto an iPod. Importing the original unedited aifc file sees it described in iTunes "Kind" as an aiff file.

As I indicated, Apple applications rely on content rather than the file extension. Since this internal data is not based on the file extension, iTunes can tell the difference and copied the file to the iPod based on these internals. Am, however, surprised that the file will not play unless perhaps it is because iPod is not 5th Generation. (I.e., it doesn't know what to do with a MOV file type.) In any case, if your default iTunes default import setting is AIFF, then you can always reset the file container properties by using the "Convert Selection to AIFF" Advance option. (Or you could have "exported" the edited file material instead of "saving" it in the first place.)