The first moments of hearing a new group are critical, even if one is familiar with the component parts. In this case it is the debut of the trio of guitarist Ava Mendoza, figure in the harder realms of avant garde jazz; violinist Gabby Fluke-Mogul, traveler in the circles of non-idiomatic free improvisation; and drummer Carolina P�rez, co-founder and driver of the excellent feminist death metal band Castrator.

In a beloved Saturday Night Live sketch, Christopher Walken, playing fictional record producer Bruce Dickinson, repeatedly tells Blue �yster Cult that they need "more cowbell". Turns out what free improvisation really needs is more tortured whispering and double-bass drumming.

Both are abundant, the former by Mendoza, in opener "Puma Punku", a billet of mystical groove with heavily effected violin in a WWI biplane battle with guitar. "Mama Huaco", which follows, begins more sedately yet is more ominous, layers of guitar like solar flares, before drums drop in for a conversation recalling the affinity of the Van Halen brothers.

Mendoza and Fluke-Mogul are regular partners and spent time with P�rez before the recording session, so the results have more cohesion and thematic drive than is typical for spontaneous music but less of the often-stultifying rigidity of metal. Pieces move along vast sonic landscape, churning through viscera at one turn, then evoking souls released from their mortal torment at another.

This variance in approach is best heard in the middle of the album, with "Trichocereus Pachanoi", "Amazing Graces" and "Partera Party", the first, another duet of guitar and drums in a soundtrack to a medieval torture session, the second moving from Mahavishnu Orchestra demo to Eddie Lang/Joe Venuti fever dream, and the third a voracious rhythmic exploration between violin and drums.

If the first moments were critical, the final ones were the most surprising. "Mama Coca", the longest track, closes the album on an almost upbeat note, the trio at its most restrained and tuneful, a (relatively) soft landing for whatever ears you have left.