I used the Song window periodically 20 - 25 years ago. Hardly ever, now. It's still there for backward compatibility with old files, and I appreciate that. If I were creating songs now with that same technique, it would still be a wonderful tool. The basic premise is this:
1. Sequences are "Chunks."
2. Chunks can be stacked, laid end to end, or even piled up randomly.
3. The Song window is where you can do that.
It was some of the original "loop" software. Create any number of phrases at a certain tempo in MIDI, each in its own Chunk. Now stack them in the Song window to create a song. A baseline or rhythm element can be laid down any number of times to make a verse, bridge, or whatever you need it to do. Stack harmonic phrases on top of that, and melody on top of it all. Any element stacked in the Song window can be shifted any amount, placed with precision, or just tossed in. It's up to you.
The window suffered some serious shortcomings. You could not use multiple tempos. Ideally, I would have liked to change tempos for some of the chunks within the window. There was just one tempo track, and it affected payback speed of all chunks. I sometimes wanted each chunk to follow its own conductor track, but they all followed only the one designated tempo chunk. (seems like that would have been the top chunk, but I can't say for sure... been a long, long time)
Again, I don't remember for certain, but it seems like it played each chunk "as-is," so you couldn't transpose a chunk within the window. That would have been nice for baseline, harmony and rhythm elements. And it seems such an obvious need that it
should have been possible. I just don't remember, but I think that was one of the frustrating things about the Song Window.
The Song Window had other uses, as well. Combining tracks and making a new Chunk was the main one. It served very well for creating new chunks from several fractional ones. For instance, if you're working on a song, you may have an idea for the bridge. You play it and record it in MIDI. Or if you're doing classical style composition, you may have an idea for an exposition "A" theme in a Sonata, then you come up with other themes, or modified ones, then you do bits of development, and you see how they fit together, but actually doing that would be a tedious job. Enter: the Song Window. Just stack them and fiddle with their positioning until everything lines up. You can place them at markers (I think???), or you can create columns at certain bars/beats, and drop a chunk right on that.
Even combining just the better first half and better second half of two different chunks into a complete "best" sequence was easy to do in the Song Window.
After your puzzle is put together, one command turns that Song back into a single Chunk. The complete Chunk — or Sequence — is now ready for final editing and finishing. The problem in the Song window was that it's a whole different graphic interface. You aren't seeing MIDI anymore, but just graphic elements representing chunks, layers and time. You can't edit MIDI from the Song window. It opens a chunk when you double click one, and you edit that chunk, but if that chunk is used over and over, you have just edited all of them. So, the Song Window is not the ideal place for editing. Its function is powerful, but limited to its specific purpose.
All that sounds well and good, but most of those processes are now very easily accomplished in the Tracks Overview Window. (Now, it's just called Tracks) You can drag and drop chunks into chunks via the Tracks Window. You can select any sequence of MIDI events and drag that selection to the Chunks Window to create a new chunk. Then drag it to another chunk's Tracks window, if you like. See how flexible DP really is? They don't make you use the Song window when a more natural, omniscient view is available in the Consolidated Window and Tracks window. SO, there are at least two ways of doing "Song" functions in DP, and actually more, but that's not my current focus.
Conclusion:- If you want to work that way, the Song Window is a dream come true. So fast. And once everything is done, you convert back to a chunk and continue on your merry way. But it seems to me that development of the window ceased 25 years ago. It could be that backward compatibility painted MOTU into a corner from which there was no place to go. Whatever the case, every time I use it, I think of a hundred ways to make it superb, but it's not going to happen. The Song Window is 1988 staring back at you down a long road of amazing improvements, a road that it didn't get to travel. Left behind, it is a reminder of the history of a brilliant piece of software.
Shooshie