Saxophonist Nat Birchall has been busy over the last couple of years, offering up a string of inspired collaborative albums, including a fine dub-wise excursion with Al Breadwinner and a brilliant tribute to Yusuf Lateef created with his regular Quartet of players. His latest album, "Mysticism of Sound", is a slight departure from his regular sound - if he indeed has one, given his exploration of many strains of jazz over the years - for two reasons. Firstly, it's an impressively evocative exploration of Sun Ra-inspired space jazz, with his meandering and emotive sax solos acting as spiritual guide throughout. Secondly, it's a genuinely solo album in which there are no guests: each and every instrument, including synths, bells, drums and bass, were played, was played by Birchall himself.