Free improvisation has rarely seen significant new movements as influential as the small group of Tokyo musicians once labeled as "onkyo", who have now been a primary driving force in contemporary improvisation for a full decade. Over that decade, these musicians have been responsible for some of the strongest and most radical work on Erstwhile, and Soba To Bara sits firmly in that lineage.

Ami Yoshida strives to create a pure sound, abstracting her voice until it becomes almost completely unrecognizable. She created her unique style with no conventional training, initially inspired by Meredith Monk. Cosmos (with Sachiko M) and Astro Twin (with Utah Kawasaki) are her two longest-running projects, and their split release won the 2003 Ars Electronica award. Outside of Japan, Yoshida is solely known for her vocal work, but within Japan, she is a highly regarded writer, poet and comic book critic, with one novel and countless magazine articles to her credit. This is her third release for Erstwhile, following Cosmos-Tears and a s o (with Christof Kurzmann).