A "dampened" sound can be created by resting the right hand on the strings while strumming. This sound can only be achieved by placing the right hand close to the bridge, as illustrated in the following photographs.
In rhythm notation, the dampening technique is indicated by a small D placed above the strum symbol, as shown in this next example.
The dampening technique is often used in conjunction with bar chords, playing only two bass strings. For root 6 bar chords, play the 6th and 5th strings, and for root 5 bar chords, play the 5th and 4th strings.
G (Bar chord)
Try the following progression using this same rhythm. You will notice that the F sharp and B are passing chords, played only on the "and" portion of the 4th beat.
G (Bar chord)
* For the open E chord, play only the 6th and 5th strings.