That's a grey area. How wide is "earshot"?

- A set of speakers in a room in your house.
- Multiple sets of speakers in multiple rooms in your house.
- Multiple speakers as above, but wirelessly connected so you can have a set of speakers out in the back yard.
- As above, but IP enabled so you can use non-proprietary wireless on your home network.
- As above, so you can connect to your home music server over the Internet from your phone while out jogging or driving in your car.
- As above, so you can listen on your PC while at work.