Probyn brings a hidden musical element to the Brian Wilson Band that is not unlike what Al Jardine brought to The Beach Boys. He plays guitar, bass, banjo, keyboards, trumpet, French horn, Flügelhorn, various lower brass instruments, and the tannerin (a theremin emulator, featured on "Good Vibrations"), and adds a tenor voice to the harmonic blend. His guitar playing has garnered praise from no less than Eric Clapton, who complimented his slide guitar playing.
He also is a long time Beach Boys fan. To date his fanhood, back in the early 1980s, Probyn placed a classified ad in L.A.'s Recycler, pleading that Capitol Records would release the Beach Boys "SMiLE" album. Little did he know that two decades later he'd be playing and singing on Brian Wilson's version of that very album.
He founded Valentunes, a music company creating personalized musical Valentine messages, and wrote and recorded 19 songs for a Children's TV Workshop science series. Probyn is also a summer director at Apple Hill Center for Chamber Music, and has composed and recorded for several music libraries.