D.C. resident Richard Chartier, above, uses computers and synths to create ambient art that hums like a chorus of charged particles. Chartier’s latest release, “Built Through,” is a collaboration with Robert Curgenven, and the duo remix and edit each other’s compositions and recordings to create a colossal yet minimalist soundscape. This is headphone music — true sound-art whose fascinating creative process is too detailed for this tiny column.

Pinkcourtesyphone’s “Foley Folly Folio,” recorded between 1997 and 2011, is the debut by Chartier’s alter ego. Whereas releases under his own name are often about exploring specific artistic processes, the comparatively more maximalist and free-form Pinkcourtesyphone pieces wouldn’t sound out of place next to analog-ambient pioneers Tangerine Dream or early ’90s post-rave comedown music.

Both albums are available via Chartier’s Line label (Lineimprint.com), which also just released Frank Bretschneider’s “Kippschwingungen,” featuring droning, modulating music composed on the Subharchord, a rare East German instrument from the ’60s.

All of Chartier and Line’s releases reward close listening. How else will you hear an atom sing?