One of the greatest jazz guitarist of all time was Wes Montgomery. He played guitar with his thumb and made popular the octave slide where he would simply add an octave to fatten up the sound. If you ever read Wes Montgomery's bio it says he developed this technique to keep the noise down and not to awake his family or neighbors.
So his octave technique was basically developed by accident so they say. Wes was noted to study Charlie Christian, John Coltrane to name a few. Check out Wes Coast Blues by Wes when you get the chance you will be glad you did. Below is some examples of Wes Montgomery playing technique. Take note of the fat tone you get by playing with your thumb!
Example 1.
Heres a basic melody played without the octave.
E||-----------------------|-----------||
B||-----------------------|--8--------||
G||--5---7-5---7-9--------|-----------||
D||-----------------------|-----------||
A||-----------------------|-----------||
E||-----------------------|-----------||
Example 2.
Here's the same melody played Wes style.He would simply add an octave to the original note to give it a dark fat sound.Make sure you play this with your thumb not your pick.
E||-----------------------|-------||
B||-----------------------|--8----||
G||--5---7-5---7-9--------|-------||
D||-----------------------|--5----||
A||--3---5-3---5-7--------|-------||
E||-----------------------|-------||
