I am making a reply to Michael Concordia with the loud piano.  This
may not be the total answer; however, any help is better than none.

There is a product on the market from a professional piano restorer
that will help soften the sound emitting from your piano.  I know it
works because I installed one for another person that was taking piano
lessons.  Most people don't want to listen to an occasional slip of the
finger and listening to those ill notes.

This is what he calls a soft rail.  This is installed in place of a
mandolin attachment and, instead of the usual tinkle of the metal
strips, there are pieces of felt hanging down between the hammer and
the strings, producing a much softer sound.  The nice thing with this
is that it doesn't require a piano technician to install; then if you
want the full piano sound just push in the button and the felts are
raised not to interfere.

I don't know if these will be good for permanent usage, it maybe was
intended for intermittent use like a mandolin attachment.  I believe
these are rather inexpensive kits.  You can get this from

  Jensen Player Piano Co.
  1446 116th St
  Chippewa Falls WI  54729
  Phone/Fax: 715-835-7264

Have fun

Ralph Schultz

 [ Many Yamaha vertical pianos are equipped with a felt strip mute
 [ like this, engaged using the middle pedal.  It reduces the sound
 [ quite a bit.  -- Robbie