I hate to see an ananswered post so even though it's been a while, here's my two pence:
Your best best for being able to hear it around the house is something wireless that you can take with you. We have a Jambox which is brilliant. It connects via Bluetooth and is loud enough to fill a hall full of shouty kids, plenty loud enough to be heard across the floor of the house and light enough to move upstairs without worrying about cables and leads.
They're not cheap - about £150 - but I think it's worth it for the amount of use we've had out of it. Can take it out and about camping and everything!
Can anyone help? Every party we have in the house is a disaster since my dd and ds lost my ipod with everything on it. Can´t afford a new one and fed up of having no success with mp3 players (yes, I know, but I am a complete technophobe) and now have a samsung galaxy s plus on which I´d like to put some music and then plug it into a docking station and hear it aruond the house. What do I need to buy? Do I need to spend a fortune? I find these shops offputting when you´re as unclued up as myself. Thanks.