Hall's musical style develops with every new album and collaboration he engages in. His approach to music is unique - he views music as a way to break all barriers, not limited to music, as well as to share his discoveries with others. Music is a vehicle of peace for Hall and he therefore makes it a goal to reach out to others and communicate his music, teaching seminars all over the world. He is innovative and always interested in new modes of musical expression to further his ability.
Hall's tone has been described as mellow, warm, gentle, subtle, rich, and lightly amplified. Like the guitarist Charlie Christian, his solo work is influenced by the horns, specifically saxophonist Sonny Rollins and his virtuosic and adventurous licks. Unlike other musicians, Hall's work is not necessarily recognized by a signature riff but rather his expressive capabilities. As an arranger, his solos are aptly constructed, taking into account harmonic, melodic and rhythmic elements. They are composed with both feeling and technique with clarity as the ultimate goal.
For Hall, experimentation is key. He is especially innovative with instrumentation, mixing classical with jazz by adding violinist Itzhak Perlman into the mix. Furthermore, in 1957, he played in a trio with saxophonist Jimmy Giuffre and trombonist Bob Brookmeyer, without any rhythm section. Without piano, bass, or drums, the three musicians improvise at the same time, keeping rhythm themselves. Similar to Duke Ellington, the other artists on the record influence the composition and he creates music to showcase their talents as well. Furthermore, he is always open to what is new and what others are playing, including the guitar synthesizer