Le cachot lumineux by Half Evidence
Half Evidence is a free improvisation duo formed in 2012 by Charles premier & Kecap Tuyul. Le Cachot Lumineux was improvised & recorded live on 11 october 2012. It shows their most droney / atmospheric (but not exactly quiet) side. It was released in february 2013 as the first published album of the duo.
Also available in lossless (flac) format from archive.org