This is not exactly a Gypsy or Musette accordion question, but since it's been bugging me for years, I thought I'd ask it here.
German and Tyrolean accordionists produce repeating 3 or 4-note chords with blinding speed--like 16th notes as fast as 116 beats to the minute.
What type of accordion is capable of doing this and, most importantly, how is it technically achieved on the player's part? The hand cannot go up and down on the same keys as fast as that!
Thanks for dispelling the clouds on this.