Я прям боюсь уже  Гугль еще больше страху нагоняет: Middle Pedal: &#39;Sostenuto pedal&#39; (on grand pianos) &#39;Practice pedal&#39; (on uprights)on grand pianos, the middle pedal holds up the dampers of which ever key is being pressed at the time the middle pedal is depressed. thus you can &#39;hold&#39; a few notes down (sustained - hence sostenuto - like having 3 hands to play the piano) while all the other keys and dampers act as normal. very useful for something like liszt&#39;s consolation no 3 in Db where you need to hold down the low Db in the left hand and still change the Right pedal with the harmony changes.on uprights, most middle pedals pull down a thick sheet of felt that dampens the entire hammer action so the sound is on the whole, much quieter. suitable for practicing late at night, in crowded apartments etc. Видимо, нужно выпить, шоп понять эту симфонию