GELLERMAN: You can tell a lot about an instrument made from wood by studying the pattern of annual tree rings - the instrument's age, where it came from. The study’s called dendromusicology. Well, Austrian artist Bartholomaus Traubeck takes tree rings one step further. He turns them into music – in a composition he calls "Years".

To make tree-ring music, Traubeck saws thin cross sections from trees, then, applying a mathematical formula, he plays the platters on a device that looks a lot like a turn-table.

TRAUBECK: The tree slice is turning like a disk and the tone arm is constantly being moved to the inside of the disk like on a regular record player. The difference is that basically it’s just a camera and this camera is a modified camera, a very fast one, and the camera has just moved in and it waits until there is a tree ring passing the camera's field of view and then it is translated into a sound. Sometimes it is a series of piano tones, sometimes it’s just one sound and the melody is defined, for instance, by the rate of growth. In essence, I play the tree’s year rings.

GELLERMAN: This first piece that you recorded, what kind of tree did you use?

TRAUBECK: It’s a fir tree and it’s very minimalistic because it grows very fast and therefore it has big gaps in between the year rings.

GELLERMAN: It’s a very dark piece of music.

TRAUBECK: Yeah. I have an algorithm that defines what kind of tree gets what kind of mixture of scales, and this is by the color of the tree and the overall texture of the wood and stuff like that. So, whenever you put a fir tree on, you will get C minor, usually- that’s a little dark sounding.

It’s sort of a poetic translation into music. Every time you put the record on, even though it’s the same slab of tree, it will be slightly different, because I would have to start at the exact millimeter point of the record every time, which I can’t. If I would have to say what part of the music is coming from me and my decisions and what part is coming from the tree, then I would have to say, I guess 50/50.

GELLERMAN: So, different trees produce different music?

TRAUBECK: Yeah, sure. If I put on an ash tree, it produces some completely different piano music.

TRAUBECK: The ash tree is kind of… it has a very interesting texture, the year rings are very close together, it’s very compressed and it’s very complex. It has a lot of information in there and they grow really differently from something like a fir. And I think you can really hear that.

TRAUBECK: But you can really hear the structure. There are some rhythms, if you listen closely, that always repeat. For example, with this one, I really know that there is a part where the tree grew in a special direction a little bit more than another one, and you can really hear this with every revelation.

GELLEMAN: What happens when it goes by a knot or a crack in the wood?

TRAUBECK: It usually interprets that as a signal. It computes that the same way as it would do with year rings. And since there’s a lot of signal, there’s a lot of sounds at the same time - it’s like just hitting your fists on the piano.

GELLERMAN: So, why did you use a piano? Could you have used a guitar or a cello or an orchestra?

TRAUBECK: Yeah, I could have, but I felt that a piano is an instrument that always sounds a little pleasant any way you play it. It’s an instrument that people are really used to - to the sound and the feel that is associated with it.

GELLERMAN: We’re going to hear the walnut music, if you could just describe that for us.

TRAUBECK: That’s really stress-y and artsy (laughs)

TRAUBECK: There’s so much data in there, and at the same time there’s not. Because my machine reads a lot by brightness and contrast, and the walnut piece is very dark. There’s a lot going on without a lot of progression, actually.

GELLERMAN: Yeah, it’s got a nice beat, but I don’t know if I could dance to it.

TRAUBECK: (Laughs).

GELLERMAN: Do you like the music, the sound of this music?

TRAUBECK: The sound of this machine?

GELLERMAN: Uh huh!

TRAUBECK: (Laughs.) I don’t like it anymore to be honest. I’ve worked on this quite awhile now. At first, I found it really fascinating, but like anything, I have to forget it for awhile to be able to listen to it again. So, right now, it’s a little too much for me. But, yes, I really do like it.

Tree Ring Record Scratchin

GELLERMAN: Bartholomaus Traubeck, thank you very much.

TRAUBECK: Yeah, thank you for the interest. I’m looking forward to whatever you are doing with it.

GELLERMAN: Bartholomaus Traubeck is an Austrian media artist. This cut is from a slice of Common Spruce. The music goes round and round at our website LOE dot org.