Berlin based British tuba virtuoso Robin Hayward has conducted extensive research into the microtonal possibilities of his instrument, and his articles on the subject involve some serious discussion of tuning systems peppered with plenty of forbidding mathematical equations. Fascinating though the subject might be from a theoretical point of view, there's no need for the listener to be familiar with the 17 note undertone rows and altered cent deviations to appreciate the delicacy, sensuality even, of the single 32 minute piece that makes up this debut album of his tuba trio with Martin Taxt and former student Kristoffer Lo, whose idea the project was.
Lo and Taxt plays standard contrabass tubas in C, while Hayward's instrument is a bass tuba pitched a fourth higher and equipped with a specially modified set of valves allowing him to pitch microtonal intervals with extraordinary precision. In the opening section of the piece he's the one responsible for the tiny pitch inflections, elaborated and fine-tuned (literally) during a period of extensive rehearsal.
As English microtonal composer Frank Denyer has pointed out, such fine differences of a few cents tend to be percieved as changes not in pitch but in timbre. Indeed, the fluttering beat patterns and rich, velvety sonorities of Microtub are light years away from the awful farting oompah nightmare most folks might expect in a piece for three tubas. While the central section sounds like the purr of a giant cat, the resemblance to the human voice in the opening and closing sections is striking, despite the musicians' studious avoidance of singing and playing simultaneously.