Here's another interesting tidbit from Ian Bousfield's master class at the International Trombone Festival...
He described a 'typical' comment from an American player:
"I like this trombone. I can go from soft to loud without the timbre changing too much"
He contrasted this with a typical European player:
"I like this trombone. I can go from soft to loud and get a nice change in timbre"
So, in his view (if I understand correctly), Europeans want a greater variety of timbre in their playing.
Here's a corollary idea - as a trombone gets louder, the sound gets brighter. It would seem that, from Bousfield's perspective, Americans view this as a problem and Europeans view this as an advantage.
I could imagine an American complaining, "This trombone gets too bright when I play loud."
I could imagine a European complaining, "I have to play too loud to get the brightness I want."
A while back, I got called on short notice to fill on playing principal with the Charlotte Symphony. The main piece on the program was Symphonie Fantastique. The guest conductor (who was Swiss I think), kept egging me on to play louder and shorter. He also asked me to attack the notes with more and more accent. We were sitting right behind the trumpets and the first trumpet was none too pleased with my assault on the back of his head. Whenever I backed off, however, the conductor got on me to play out more. He even said, "First trombone, I want you to play those notes as loud and accented as possible." (not something you often hear in an orchestra rehearsal).
Finally, I opened up more and played in a style I would normally reserve for the loudest shout sections in a jazz band. This evoked a big smile and a 'thumbs-up' from the conductor while my trumpet colleague's ears turned red with anger. Tough spot to be in.
Looking back on it, I wonder if the conductor was wanting a more brilliant sound and I was just having to play that loud to give him the timbre he wanted.