I've noticed that the accordions of many of the modern French musette players have a particular sound (e.g. Michel Macias' version of Montagne Ste. Genevieve). I also hear it in Julien Labro's (of the Hot Club of Detroit) accordion. I'm wondering how they get this. I see that many of them play Cavagnolo or Fratelli Crosio accordions. The reed combination sounds like 2 middle reeds dry-tuned ("violin" register). However, there is definitely something else present in the structure of the sound that I don't hear anywhere else. I haven't yet heard it in a piano accordion. It reminds me of a chorus effect. Can anyone identify this or explain how this quality is obtained in the sound? My best guess is that it's related to the resonating chamber on the instrument (boîte de résonance). Anyone know if this is this the same thing as a "cassotto chamber"? I've also noticed that these accordions are rather expensive. Also, does anyone ever dry-tune 3 sets of middle reeds?