Experimenting for the first time with the Session Drummer loops provided.
 
I want to clone the loop track, the isolate just on note for each cloned track (i.e., a kick drum track, snare track, etc).
 
How can I easily remove all notes from a MIDI track except the note I want to keep (i.e., kill all notes except the kick drum note)?

Well, there is a CAL script that will split each drum note to its own track, if that's what you want to do.
 
It is called 'Split Note to Track.cal', and here is the doc at the beginning of the script:
 
"
;
; Split Note to Tracks.cal
;
; This routine modifies a source track, splitting it by note# into
; separate destination tracks. Only notes are split ... all other
; track parameters (Controllers, Tempos, Meters and Markers),
; if any, remain in the source track.
;
; Use this routine for splitting up a drum machine or other type
; of instrument track where voices are assigned by note number.
;
; = Courtesy Red Nile Productions 1993 (714)498-7515 CIS:70044,2733
;
; = Modified 12/10/93 by Greg Hendershott at user's request to
; have this display notes as names (like C#5) rather than numbers
; in the track names. Caveat: The note names always use sharps
; and assume BaseOctave=0."
 
Bob Bone
 
 

open the prv, use the keyboard to click on notes (this will select every note in its path)
once you select all the notes you need except the ones you want to hear, right click on any note use the mute tool.
 
you could always just use the solo mute buttons on the track view if you have the kit split up.

I believe you want to run the "Split Note to Tracks" CAL script. This will break out a MIDI track into individual tracks, one for each note. This makes muting individual notes easy. Another way is isolate the drum kit elements in Session Drummer is to work on the audio side. There is a stereo pair for each drum pad in Session Drummer. The easiest way to setup a multi-out instance of Session Drummer is using a track template. Right-click in the track view track header, select a template from Insert from Track Template > Soft Synth Track Templates > Session Drummer 3.

This just came up in another thread. 
 
Alternative to Cals and fairly fast is this: 
 
Clone the MIDI track as many times as parts you will split out ( say 5) 
Now simply open each track in turn in piano view and using the keyboard along the left side highlight all but the one note you want to keep. You can drag the mouse down the keys. Delete. Done. Re name the track.