There are drones that channel the hum and vibrance of machinery. In fact, most drones do. Much of what makes a drone a drone, as opposed to, for example, a note held for an extended period, is the warmth of its seemingly uncountable overtones, the sheer spread of warmly contrasting harmonics. Often as not, drone recordings leave the drone on its own. Call it the single-malt approach to composition. Then there is work like “My Grandmother Smiles at Me”by Russian musician Murkok, which puts the drone to melodic use. Here the singular yet internally rambunctious drone plays out a slow, peaceful sequence of notes. There’s no division between those notes. It’s pure resourceful melisma, endlessly transformative shifts that are glacial from a pop music perspective, even from a classical music one. It brings to mind Discreet Music”“era Brian Eno, as well as Gavin Bryars when he was busy sinking the Titanic.