My wife plays 2nd/3rd cornet in the same bands as me, she often uses a practice mute at home to avoid annoying the neighbours. She bought me a Denis Wick baritone mute for my birthday, in the hope that it would enable me to practice quietly. However I soon discovered that if you put plenty of air through it, particularly in the higher register, it reverberates producing a tremendous rasp like a trombone. I hasten to add that I usually practice when the neighbours are out. She now regrets her purchase - I most certainly don't! Have other readers experienced interesting or unexpected effects from mutes?