Thursday, November 6:

This week, watching Metropole rehearse the four new compositions that'll make up Friday's Double Dutch concert, it's often seemed that the process of rehearsing new music recapitulates the composing of it: that composer and orchestra both make the same long journey from mastering isolated fragments to assembling them into a smoothly-integrated sequence.

For example: On Tuesday, when Metropole made its first pass at Guus Janssen's Four Songs for sheng and orchestra, conductor Jurjen Hempel spent a few minutes working with three players (including guest soloist Wu Wei) on a fast and zigzagging unison passage for sheng, xylophone and piccolo. When the musicians had it down, they placed it passage in context-the passage appears in a sort of call-and-response between trio and orchestra. And then, eventually, we heard that episode in the context of the entire composition.

Yesterday/Wednesday, and again today, Hempel kept returning to Four Songs' slam-bam orchestral finale, first in smaller chunks and then in longer sequences, until the orchestra burst into a big jazz band. Today, Wu Wei on sheng-China's mouth-blown miniature pipe organ-ignites into a fireball on his final, improvised solo, the one over jazz chord changes he'd been nervous about on Tuesday. (See "Zwingt wel.") It's the most astonishing thing heard yet this week. Afterwards he seems equally intimidated and exhilarated by it all. So much information, he marvels. But the experience: "Amazing, amazing."

Context: on rehearing, it's easier to spot various episodes where clarinets or pulsing strings or a groundswell of trombones (or Guus's own crude harmonica, one mouth organ shouting out to another) bridge the timbres of sheng and Western orchestra.

So that's the building up: the construction of a piece. But sometimes you have to tear down too. This morning, Hempel tells the wind players to get out their pencils, because sometimes you have to "kill your darlings." After yesterday's rehearsal, Maarten Altena decided to radically pare back the non-string parts on some sections of his Song Book (Words of Whitman): whole passages for woodwinds were stricken from the score, leaving the strings more exposed. Altena: "I was looking to make it almost like electronic music-overtone rich, but with a thin sound." Transparency is always the goal.

Editing is a big part of writing too: knowing where to use the scalpel, to cut away inessentials.

Altena is composer is very particular about textures: at a couple of points on "A Clear Midnight," one percussionist rubs sheets of sandpaper together (in a way that somehow does and doesn't recall a jazz drummer playing with brushes). On Monday, Maarten had told him the sound was too high-pitched, and suggested a coarser grain. (After writing for Slagwerk Groep Den Haag, I know my sandpaper, he says.)

The string writing retains all of its bite, and today it strikes me as less Ives-y and more itself. Soprano Claron McFadden's tone is so pure and sweet, her pitch so accurate, you can understand why so many composers want to write for her. But even she grapples a bit with Altena's melodies, which might leap by more than an octave.

Metropole and metal band Noneuclid rehearse Florian Maier's BLACK VORTEX CATHEDRAL together this afternoon, integrating their parts. (Apologies: in Monday's blog entry I not only mangled its title, but missed that it's all in capital letters.) The Metropolers seem to dig it more and more-there's a smattering of spontaneous applause when they're done. I'm not sure what any of us were expecting from the German guitar band the composer came up playing in-he's on an eight-string axe for this performance-but they don't miss a cue, and hit their marks. They're ready.

Janssen has Wu Wei, Altena has McFadden, Maier his metal band. Willem Friede's Pod features soloists from Metropole itself, in particular flugelhorn player Rik Mol and alto saxophonist Marc Scholten, who solo at very different tempos. In moving from classical music to jazz through rock and roll triplets, Pod is a showcase for the orchestra at large: a love letter from someone close.

"They asked me if I wanted to use a guest soloist," Willem Friede says outside, during a break. "But I thought, there are some great soloists in the orchestra who tend to get forced into the background on programs like this, and I wanted to bring them out, if only briefly. Also, I wanted to get them to do things they normally don't-like having the rhythm section play a 12-tone, serial improvisation.

"After working with them for a couple of years, I feel comfortable with them. I first wrote for them in 1996; Rob Pronk, who was their regular conductor then, was one of my teachers at the Rotterdam Conservatory. I've written a lot of arrangements and pieces for Metropole-in fact this afternoon, I'll be working on an arrangement, for Benjamin Herman.

"As for the title Pod-which could also stand for Payment On Death, as in an insurance policy-that's just to get your imagination going. But yes, the idea of scrolling through an iPod is behind it. Actually, two iPods, running simultaneously."

That's the key to the whole piece. the band/ork will be playing (with) one idea, then another will slide in behind it; then the first idea will wrap up and another one will emerge in counterpoint. (And ideas come back.)

"The interesting part of this event for me," Willem Friede says, "is to see what everyone else will come up with, and to see how all the pieces come together to make a concert. This kinds of music may seem different from what Metropole is used to, but remember, in a way everything they play is new music: They're looking at freshly written music every week. Which takes a certain attitude."

Then he goes back inside to hear what Altena wrote. The Whitman songs are as wildly beautiful as an unpruned vine, even after he pruned it back.

The concert's Friday, 20:00 at the Grote Zaal of the Muziekgebouw aan 't IJ. Micha Hamel and I will introduce the pieces. You gonna be there or what?