It's when I play guitar or bass with a vocalist or another instrumentalist, just the two of us...though not necesseraly we play Bill Wither song :)
When playing with a non-chordal instrument/melodic instrument (an instrument that only sounds a note at a time, such as: vocal, saxophone, trumpet, etc.), I usually play the role as a rhythm sectionist that provide the chords & groove, where else the vocalist/saxophonist/trumpeter has control over the melody.
When playing with another chordal instrument, such as: keyboard, bass, guitar, etc; both instrument can take turn to be the rhythm sesionist (chords & groove) and melody player.
Playing duet with a percussionist is also unique combination as it enhance the guitar's groove while the guitarist/bassist is still in full control of harmony & melody.
"Wave" (Carlos Jobim), a duet guitar with Rick Smith.
"The Nearness of You", with Michelle Chua at Singapore Cricket Club, November 2015.
"Sunny", performing for a house party with Karen Xavier on vocal
"Shanghai Tan", a bossa nova version with Julian Cheong on vocal, January 2016.
With Anne Weerapas - vocal for "Christmas Wonderland 2015" at Garden by the Bay
"Sweet Child O'Mine", with Julian Cheong, Christmas Eve at MAD Museum 2015.
"Close to You"
With Michelle Chua, a regular live music gig at Stuttgart-Cafe, Singapore, March 2015
"More Than Words", Joanna Dong on vocal (joannadong.com) & Daniel purnomo on bass, live music at Singapore Cricket Club.
"Rainbow Connection", with Dominic Cai at MAD Museum & Bistro, Singapore.
"Blue Moon", with Michelle Chua, a regular live music gig at Stuttgart-Cafe, Singapore, March 2015
"I Will", with Michelle Chua, a regular live music gig at Stuttgart-Cafe, Singapore, March 2015