Hi Cedub,
Just to echo what Daveyboy said; there are no equivalents in Logic to multiple Sequences in DP. And since there is no equivalent to multiple Sequences within a single Project, the idea of the V-Rack isn't really relevant.
Having said this, there are a few, far less elegant than DPs Sequences, ways of possibly getting close to what you want. In the scenario you describe of tracking multiple songs, you could pack each song into it's own folder. That way they can all access the same effects processing and software instruments like V-Racks allows in DP. One big limitation though, compared to sequences, is that folders do not contain unique tempo tracks. There are a couple of ways of managing this though:
First, if you are tracking multiple songs live and the DAW tempo is irrelevant, you can just pack folders with each song, and have the folders stacked vertically, all starting at the same bar position. Just keep them muted except for the current one you are working on.
If you do need to work with the DAWs tempo (if you are using MIDI, etc) there are two scenarios that will work:
1. Pack each song into folders and stack them vertically all at the same time position as described above. Logic allows for 9 alternate tempo tracks. So, you can switch to a new tempo track and set it to match each song's tempo. The limitation is that there is a maximum of 9. And you will need to switch tempo tracks manually when you mute/un-mute the different folders/songs.
2. Pack each song into a folder but lay them out horizontally along the timeline. This way you don't need to deal with muting/un-muting them. You can use tempo changes at each new song's location as necessary. Plus you can put markers in at each new song/folder; so that it is easy to jump back and forth between them.
In these scenarios, all plugin-ins and instruments are available to each folder/song since everything is in the same Project. So the V-Rack thing is covered.
Another more "Logic-centric" approach would be to work on your first tune, get it set up as you need with all of your plug-ins and instruments; then when it is done, do a "save as" and save as a new project for the second song. Then in this new document, delete the song data, and start your second song. repeat for each song. Drawbacks to this: you need to open and close projects for each song. And plug-in changes you make to one while mixing will not automatically updated in the subsequent song/projects. But to work around this you could use channel strip settings to bring in channel strips with plug-ins laid out as you want as they develop. Or you could use the import tracks function to bring in Aux tracks with effects plug-ins for mixing. Although, this isn't a particularly elegant way to work, since you would then need to assign the channel strips to the imported aux tracks as necessary.
So, as you can see, there's no one magic answer, but lot's of possible work-flows to suit the tasks at hand.
Welcome to Logic
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