My father used to tune pianos on weekends, and he showed me a little about them. First depending on the note, the deepest notes of a piano are one big string tightly wrapped around another large string. As you go up the scale, it becomes just one string being struck, then higher up 2 strings, and finally at the top 3 strings are being struck in order to produce the volume needed.
My thinking would be to press the 'soft pedal' down and keep it there, with a weight, giving the most damping of all the strings. Make sure that the top is down, and find a mattress sized sheet of memory foam to cover the piano with.
As for glass panes, I have used a quilt on a rack to hold it upright and put it in front of the window. Done. Same can be done behind the system. Incredible difference that you may or may not like. Adjust accordingly.
My thinking would be to press the 'soft pedal' down and keep it there, with a weight, giving the most damping of all the strings. Make sure that the top is down, and find a mattress sized sheet of memory foam to cover the piano with.
As for glass panes, I have used a quilt on a rack to hold it upright and put it in front of the window. Done. Same can be done behind the system. Incredible difference that you may or may not like. Adjust accordingly.