Not counting their more experimental works under the name Grumbling Fur Time Machine Orchestra (including a 2015 collaborative LP with minimalist composer Charlemagne Palestine), London's Grumbling Fur have progressively become more accessible since making their debut in 2011 with the full-band improvisation Furrier.

FurFour continues to refine the experimental synth pop sound the group has been pursuing since it stripped down to the duo of Alexander Tucker and Daniel O'Sullivan for the acclaimed 2013 full-length Glynnaestra.

The duo's sad, passionate vocals readily recall peak-era Depeche Mode, but the instrumentation is much more organic, and the production is far more atmospheric and multi-layered, even verging on hallucinatory at times.

The pair outfit their propulsive electronic rhythms with rustic, twangy stringed instruments (opener "Strange the Friends" features acoustic guitar and bulbul tarang played by This Heat's Charles Bullen) and heavily bowed violins and viols.

The duo excel at writing straightforward hooks, especially on the album's early standout "Acid Ali Khan," but there's still plenty of room for abstraction, integrating Coil-like scattered vocals and shifting textures worthy of Nurse with Wound into their structured tunes.

While the vocals seem dour, there's an undeniable message of hope on songs like "Heavy Days," where they sing "the sun keeps shining on these heavy days" over rich strings and tablas.

The album's shorter, more experimental pieces utilize spoken word samples that ponder extraterrestrial life ("Molten Familiar") as well as human genetics ("Sapien Sapiens").

"Molten Familiar" rides a trippy psychedelic hip-hop rhythm that wouldn't feel out of place on a Stones Throw release, and the rain-soaked "Pyewacket's Palace" is like the soundtrack to a brief, wordless revelation scene from some sort of fantasy movie.

The album touches on many different styles explored by both musicians throughout their careers, from Tucker's avant folk solo work to O'Sullivan's synth pop duo Miracle (with Zombi's Steve Moore) and less easily categorizable ensembles like Æthenor and Ulver, but it distills a multitude of influences into a singular brand of musical mysticism.