Being able to focus on a single element in your mix quickly and easily is vital to a speedy workflow.  Traditionally solo is the tool for this.  The key command “Shift-S” to solo any currently selected tracks is one nice option.

But as with all aspects of Pro Tools, there are only 10 ways to do everything.  Here are a few ways to effectively use scrub as a means to solo.  First is the scrub tool itself, of course.  Just pick it from the tool palette or hit F9, and click and drag across your content to scrub an individual clip.  This effectively “solos” the clip that you are scrubbing.  You can also bring this up while the selector tool is chosen by holding the control key.

Of course, the main limitation here is that it plays at the speed of your mouse movement (up to normal speed.  Hold option to turn this into high-speed scrub, or command+control to turn it into “fine” scrub); it can be a lot of mousing around if it’s a somewhat longer clip you wish to solo!

My preferred method is to set the numeric keypad on the keyboard to “shuttle” mode.  The option for this is tucked in preferences, under the “Operation” tab, in the “Transport” Section:

 

Now when you have the insertion point on a single clip and hold down the 6-key on the number pad, the clip is “scrubbed” forward at normal play speed.  Essentially you are soloing the one clip without having to actually solo the track it is on.

Other numbers on the keypad perform the same basic soloing/playing of a clip, but at different speeds and directions.  For instance, holding the 4-key will play backwards from the insertion point at normal speed.  The 1-key will play backwards at 1/4 speed, and the 3-key will play forwards at 1/4 speed.  Logically then, the 7-key will play backwards at 4x speed and the 9-key will play forwards at 4x speed.

An advantage of using this as a means of soloing is that you don’t actually ever have to put any track into solo and then take it back out of solo later.  Also, because it’s a scrub function, you’ll see an insertion bar moving across the clip you are scrubbing, which can help in identifying small problems in clips.

One main disadvantage of using this as a means to solo is that automation is suspended while scrubbing.  So if you want to solo an element and hear how it is being affected by automation, this method is inappropriate.

That issue aside, I find this to be an incredibly helpful means of quickly soloing a clip.