Justin's Completely Free Jazz Guitar Lessons. This is Lesson JA-203.
An excellent intro to Jazz Walking Bass using a Jazz Blues in Bb. Slowly and clearly explained.
Find the related course notes on the following link:
Taught by Justin Sandercoe.
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To get help with this lesson (and for further info and tabs), find the Lesson ID in the video title (like ST-667 or whatever) and then look it up on the Lesson Index page of justinguitar.com
Have fun :)