In some senses Sonar is an upgrade of CW PA9. however the user interface has been completely redone and several new features have been added. I guess it could be called CW PA10, but the changes are extensive enough that giving it a new name is not altogether inappropriate (although I'm sure they will confuse many people by this approach).
As for specific changes, I only do audio work - no midi. So my comments are strictly in those areas related to audio. (And based only the few days I have had of being able to work with Sonar.)
1. The interface is totally redisigned. Everything is essentially now done from the track view. The track view now also contains both input and output meters for each individual track (as well as for the main output and busses). Each track also has a minimize/maximize button which can blow up the view of an individual track with a single mouse click.
The audio view is completely gone and the waves are contained in the track view. The console view remains, but I haven't found any use for it yet. Staff and piano roll views also remain - but since they are associated with midi, I won't comment.
2. In addition to the volume and pan envelopes that existed in CW9, they have added FX envelopes. This allows you to tweak the FX settings for specific portions of a song. Nice feature.
3. Something called "slip editing". This feature lets you "hide" individual portions of a track without destroying it. For example, let's say they you have a 1-2-3-4 count in to a song that you'd like to keep available, but don't want to actually hear when the song plays. You place your mouse over the left edge of track, and drag it to cover up the count in. It's now gone, and you don't hear it. Want it back? Just slide the edge of the track back to it's original position. (You can do this on sections of the track also. Make a cut in the track, and slide left or right from the cut to cover up the material you don't want to hear.
4. Sonar has also been designed to work with Windows WDM drivers. These should give you reduced latency. (Note: These need to come from you sound card manufacturer and not all manufacturers have done this yet. Beta ones are available for Delta cards, and SB Live cards have them available also. Others, you will have to check on. If they are not available you can use the drivers that you currently use, but won't get the reduced latency offered by the WDM drivers).
Lastly, a word of caution. Sonar is release 1.0 and there are some horror stories out there about problems. Crashes, blue screens of death, etc. My biggest problem was "scratches" in playback mode (sounded like a worn vinyl record). I finally resolved this by disabling my USB hub - but it took me two days to figure this out after trying tons of other things first.
However, one you get it running stable (assuming you do), the program is great. Certainly worth the $99 I paid to upgrade from CW9.
Maybe someone else can advise on some of the midi features. I know they are touting something called DXi Synths, but I'm clueless as to what they are and what they do.
