This command is for people who wish to align a track of music that was recorded in 'free time' to a click track. The idea is to take a free time track and then have RealBand adjust the times of the events so that the music becomes a normal track that is in sync to the metronome and displays nicely in the notation window.
Suppose you recorded track number 1 in free time. You could then record, or enter, a click track on track number 2. You would record or enter a C Note on the click track at the location of each beat in the song. If the song speeds up and slows down you would have to make sure the timing of the click track corresponds with the beats of the free-time track. In other words, the click track follows the pace of the free-track rather than any metronome in RealBand. When the Align command is executed, RealBand will align the free time track so that the time locations of all the events will correspond to the beats in the click track.
There is detailed information about this feature in the RealBand Help Files. Select Track | Align Music to Click Track, and click [Help].
Note 1: Some programs also insert tempo changes to mirror the tempo changes of the original performance - RealBand doesn't. This is because the artificially inserted tempo changes usually sound worse than a fixed tempo.
Note 2: Recording a click track is easiest done from an external MIDI keyboard. The note you need to use to record a click track is middle C - all other notes will be ignored. So, when recording the click track, you will be tapping the note middle C. It is also possible to record a click track without using an external MIDI synth. You can use the Drum Window to accomplish this. To open the Drum Window, click the Drum button in your toolbar. If the Drum Window button does not appear there, add it to your toolbar using the little arrow on the right-hand side of the toolbar ('Add/Remove buttons'). You can record from the Drum Window in RealBand simply by pressing Record and mouse-clicking on the drums in that window. Once you are finished recording, press Stop. RealBand will ask if you want to keep recorded notes from .dll, to which you will answer yes. You may need to move the drum window out of the way by clicking and dragging it, because the 'keep take' dialogs will appear beneath the Drum Window plugin. The 'High Bongo' drum sound is equivalent to the note C5 (middle C), so this is the drum sound you will use. You can also use the keyboard shortcut '[' instead of mouse-clicking the high bongo drum. Any other drum sound could be used as well, provided that you transpose the track to middle C after you are finished.