To get the right wattage for your party speaker, you need to know the area to be covered for the party and the number of people present. For areas smaller than 300 square feet aim for a 60 watts speaker or more. However, for 300 to 500 square feet, a 80 to 100 watts speaker will suffice. Moreover, if it's an indoor gig then 5 watts per person attending the party is ideal. For parties where you're looking for "rave volume", then 50-100% more wattage is ideal. If your outdoor performance will only be modestly loud - say under 60dB or so on average--you can get away with slightly higher output levels (around 10 Watts per person) than this without compromising quality too badly. This is down around 87% compared to when you are playing the music loudly/ rave volume.