Jay Si Proof, or JSP, is the philosophical indie funk vision of multi-instrumentalist composer/arranger Jeff Chilton (Jay Si) whose credits include performing with The Diamonds, The Platters, Broken Social Scene, and recording on over 20 albums by Portland based ensembles. Described as "earth jazz alchemists" by Vortex Magazine, JSP was born in 2019 from the soggy jazz soaked earth of Portland, OR. Since its inception, the band has evolved through adventurous jazz fusion to low-fi jams to a full fledged funk party, all while prioritizing genuine messages of spirituality and human betterment in the midst of endless modern crises.  

Jay Si Proof has performed their unique sound across the Pacific Northwest elevating crowds in Seattle, Bend, Eugene, Rogue Valley, San Francisco, Santa Cruz and more. They have performed at venues such as Portland's Goodfoot, Seattle's Nectar, and Berkeley's Back Room; and festivals such as the Skyview Jazz Festival, Mojo Family Fest, and Turning Earth Music Festival, growing a passionate grassroots following. The band is known for their energetic performances and crowd engagement and involvement.

JSP released their EP “Closer” in 2021 to praise at home on Portland's KMHD Jazz Radio and followed up with a year of touring the West Coast from Santa Cruz to Seattle. Their music video for fusion epic "Our Lament" was shot completely on Super 8 Film and featured in Vortex Music Magazine. The "Closer" EP featured Jay Si Proof's iconic retro and utterly human aesthetic, showcasing unique hooks, melodic horns and improvisational solos recorded almost completely live at renown Jackpot Recording Studios.

In their upcoming self produced 12 track album “Care About It,” JSP presents music inspired by grandiose retro soundscapes and instrumentation packaged into neat indie song forms interspersed with the evocative moments of jazz interaction and improvisation they are known for. Jay Si Proof is led by Jeff Chilton (trombone and vocals) and joined by Lucas James (drums and vocals) JD Erickson (sax and flute), and Corey Heppner (guitar).