Unbeknownst to most in the universe, Seattle composer/vibraphonist Stuart McLeod released in July one of the region's best albums of 2015. Tetraktys (China Sea Recordings) somehow eluded me until this month, but I'm making up for lost time by immersing myself in its special aural glow.

Tetraktys consists of four tracks of minimalist mesmerism. There's a complicated relationship with numbers in McLeod's work (which he explains below), but even if you're a math dunce, you can get into Tetraktys' tonal luxuriousness and rigorously elegant pulsations. Fans of Terry Riley, Steve Reich, Lou Harrison, and Gamelan Pacifica will enjoy McLeod's glinting, undulating meditations. One odd tangent from this occurs on Tetraktys 5, which features strident, staccato string motifs that recall the ending of Love's psych-rock classic "The Good Humor Man He Sees Everything Like This," off Forever Changes—but I'm not complaining.

"Most of my music is based on number relationships," McLeod explains in an email exchange. "The Tetractys is a Pythagorean symbol of dots arranged in a pyramid and each number 1-10 is supposed to stand for something, but I'm more interested in the number relationships in music. The record only has 4 of the 10 pieces. Tetraktys 5 for example, has 5 sections, the tempi for each section are in ratios of 5, the rhythm uses quintuplets, and the intervals are all stacks of 5ths. It's very obsessive. I started the series with Tetraktys 4, 5, and 7 back in 1996 and just finished it a year or two ago. My group at the time, the SIL2K Ensemble, performed a few of the movements at the Rendezvous in 2008."

You can read more about Tetraktys in a column by former Stranger contributor Christopher DeLaurenti that previews the aforementioned performance.