We have a large through-lounge with the piano at one end and the TV at the other.
I have my computer at the side, between the TV and piano, so I can keep an eye on the kids and while I work if I have too, and also watch what the kids are doing on the computer.
However now my eldest DDs are progressing a bit with the piano and are sitting exams, they need to concentrate more when they practice, and are forever complaining about their siblings running around or chatting or making noise.
I don't let the TV go on while anyone is practising the piano but I can see how it's distracting. But it's not really fair to expect the little ones to sit still after school and not play.
Also no one can practice until after lunchtime, or after 7 as the neighbours have complained that they can hear even though the piano is against the wall next to the hall, not the party wall.
DH has a room all to himself where he has his books and computer. It's a pit but he cleans it out now and again and there is room to put the piano in there if he keeps it tidy. His room is an extension with a concrete floor and is on the other side of the hall so wouldn't disturb the neighbours.
Would I be being unreasonable to ask DH to share his study with the piano? I'm slightly miffed that he gets a whole room to himself anyhow when he's only home in the evenings. He's had a study for over a decade now, but as we now have 4 kids, I think that others need the room more than he does.