I want to talk about just intonation. I know you can look this up on the internet, but most lay-person explanations tend to be all “oh no, maths is hard” and run away from it, whereas it’s really nothing more than a bit of multiplication, and it’s quite interesting. So let’s do it.

Sounds consists of vibrations. A musical note consists of a bunch of vibrations at one frequency, the fundamental, and less at a bunch of related frequencies, the harmonics. When we define a scale and a tuning, we pick a set of notes we’re going to use, assigning them names and fundamental frequencies. Notes tend to sound “pleasant”, or at least “correct”, together, when their frequencies form nice small-integer ratios, an idea which goes back at least as far as Pythagoras. When two notes have frequencies in the ratio 2:1, they tend to sound kind of “the same”, as the higher note is the first harmonic of the lower note. This defines an octave. Most (all?) scales are based around subdivisions of the octave. Now, here’s the fun bit: it’s not mathematically possible to make all the notes in our scale have nice small-integer frequency ratios. For example, in the twelve-note scale, we have an interval called a major third, and three of them make up an octave (so it could take you from C to E, E to A♭, and A♭ to the next C). We could choose to make two of those have a 5:4 ratio (1.25x) but, to complete the 2:1 ratio for the octave, the other would have to have a 32:25 (1.28x) ratio, which is a fair bit off. The overwhelmingly common solution for a long time in Western music has been a thing called equal temperament, or something pretty close to it. With that, we fudge everything, but by the same amount. So our major third has a ratio of the cube root of 2, about 1.2599x. This is close enough to 5:4 that we can’t really hear the difference, especially since we’ve been trained to be so used to it. (The intervals called a fourth and a fifth come out at about 1.3348x and 1.4983x, close enough to 4:3 and 3:2. It is one of the odder aspects of this stuff that the numbers, powers of the 12th root of 2, happen to approximate these nice ratios so well.) With just intonation, however, you pick a fundamental to base things off, and you pick some intervals to assign the exact small integer ratios to, and you accept that getting those intervals exact means that some other intervals are going to be quite a way off — these are called wolf intervals. As you can see, there are many choices you can make about which intervals you’re making exact, and so many different just intonation tunings. (See wikipedia for some of these.)

I mention all of this partly because I enjoy geeking out about this stuff, but mostly because I find it really does help to understand why this record sounds the way it does. Because what we have here is a collection of five improvisations on a piano tuned using just intonation. In fact, not just any such beast, but a thing called The Enhanced Piano for Just Intonation, which composed Alfred Owens “electronically enhanced” to “add increased resonance and color”. I imagine that composing this way, where you have to know not just the intervals but the particular flavour of each pair of notes, must be maddeningly hard, but the results here are fantastic. This is music which is sometimes hauntingly pure, sometimes entrancingly dissonant — and sometimes both at the same time. And, despite all my waffling above, this isn’t in any way off-puttingly abstract or theoretical. I find it intensely emotional.

Loren Rush, who has been around since the 50s and collaborated with greats such as Terry Riley and Pauline Oliveros, is in the driving seat here, although there is another pianist, a cello, and a violin (most noticeably, perhaps exclusively, on the closing track). The title says that it’s a homage to Giuseppe Ungaretti, who was an Italian poet in the trenches of World War I. This album is quietly powerful stuff, which appeals to my head and my heart in equal measure.

I bought this from Boomkat. They call it Modern Classical / Ambient.