It's common knowledge that manufacturers tune the sound of each DAC model. There are the facts of product design and marketing: inputs, outputs, case materials, price points. After that, what's left are the trade-offs of different circuit designs and filter options, which are chosen with care—each has a subtle yet telling effect on a DAC's sound. Most designers try to go from bits to analog with minimal deviation from perfect. But when you look at the measurements and listen closely, you realize that perfect is elusive. One has to make choices.

In last month's column we met May Belt, whose contributions to domestic audio—made alongside her husband, designer Peter W. Belt—all have to do with reflexive perception: conditions under which a listener's comprehension of music can be altered, given the presence or absence of certain nonsonic stimuli.

While 2011’s Sahel Folk was a quiet, intimate collection of duets&#151Touré and a friend meeting over a cup of tea&#151Koïma, Sidi Touré’s second full-length album for Thrill Jockey, is a much more jubilant affair.