Joe Morris/William Parker/Gerald Cleaver

Recorded live on a hot night at NYC's the Stone, the trio's sweat-drenched playing is full of fire and intensity. Guitarist Joe Morris and bassist William Parker were two of the first musicians to release records on Steven Joerg's AUM Fidelity, which is celebrating its 15th anniversary this year. That the label is still producing recordings and that the musicians are still resolutely creative 15 years later is a testament to their perseverance and willpower. The first two tracks clock in at over 25 minutes apiece. They are jam-packed with fervour and potent playing, especially from drummer Gerald Cleaver, who is utterly relentless in his invention of responses to his cohorts and his assertions. On "Thermosphere," Morris and Parker leave behind their non-stop notey-ness for a suspended interchange of tense tapping and arco answers; it's a nice change of pace, a respite from their full-throttle pyrotechnics. Morris's motivic approach, usually within a restricted pitch range, continues unabated, even with Parker switching instruments. For "Troposphere," Parker picks up the quieter, three-stringed Moroccan Guembri, which he digs into while vocalizing enthusiastically. The last two pieces ― excerpts from longer improvisations ― are faded out rather than ending. Altitude is intellectual energy music.