Slight and anticlimactic are terms of dissatisfaction that could be used by certain listeners as a reaction to Elaenia, the first full-length from Sam Shepherd, aka Floating Points.

Those who have been attentive since the brainiac producer's earliest releases are more likely to hear the 43-minute album as a modest culmination of progressions and refinements traceable throughout what preceded it.

Shepherd began in 2009 with swinging post-dubstep/house hybrids.

Subsequent releases were pared down, increasingly graceful and organic, typified by "Sais," an austere but emotive threading of Carl Craig-style ambient techno and Lonnie Liston Smith-referencing spiritual jazz.

Even before that 2011 track, Shepherd had worked as part of a 16-member unit, dubbed Floating Points Ensemble, which took Craig's cross-genre Innerzone Orchestra and 4hero's chamber soul a few steps farther out, as a platform for vocalist Fatima.

Among the roughly four hours of Floating Points material previously released on singles and as EPs, Elaenia is closest to those highlights, though it's almost entirely instrumental, using voices only sparingly in a choral mode.

Shepherd plays a variety of keyboards that undulate, twinkle, swarm, and sometimes act merely as shadowy outlines.

There are sections when they are delicately layered over one another, sometimes unaccompanied and barely touched, as Shepherd's aim, like that of Mark Hollis circa Mark Hollis, is to make moving music that sounds quiet at any volume, simultaneously exacting yet freely flowing.

Shepherd directs his supporting players, including drummers Leo Taylor and Tom Skinner, bassist Susumu Makai (aka Zongamin), and a small string section, through a pensively paced sequence.

Some tracks could be called mood pieces but are really too defined and substantive to fit that categorization, while the relatively active and as detailed remainder -- "Silhouettes," "Peroration Six" -- is suited more for foot tapping or awestruck stillness than dancing.

Just as the latter seems to be on the brink of explosion, as its currents are whipped into a fever pitch, Shepherd pulls the plug, leaving the album to conclude with ten seconds of stunned silence.

Elaenia is fated to become one of those albums that inspires ritualistic listening parties held by small groups of audiophiles.

That shouldn't be held against it.