Subwoofer?

[Excalibur]

The simple answer is double your tops combined output, so around 800watts rms. That's the ideal world answer. However, we don't live in an ideal world, so best advice is to get as loud and reliable a cab as you can afford. Then balance the sound with the knobs on the back. They turn down as well as up you know. Match the tops to the sub, then alter the volume with the mixer


Don't get hooked up on figures, as long as you don't buy a really small one and redline it permanently you'll be fine

[paulg]

it's not the wattage that is important - you need to look at sound pressure levels (spl's) in decibels (db). For the Alto's you are looking at about an average of 124db which is so so. I reckon he's about right with the estimation of 75 - 100 people without you having to drive the nuts off them. Still, they aren't a bad offer at 800 quid or so for two powered tops and a powered sub

During your search for new speakers, you are best to look at the SPL's and not watts because it's very common now for manufacturers to put the same size amp in a whole range of speakers of driver sizes and outputs. (It's cheaper for them to mass produce one amp module rather than several different ones tailored to different speaker cabs).

The only downside is how quoted SPL's are measured - some are actual measurements in the real world, some are calculated mathematically. Others are measured using pink noise. Mackie often say that their SPL's might look lower than other manufacturers but that's because they are measured and quoted honestly. Still. it's fair to assume most manufacturers will quote the most impressive figure they can so it's still a reasonable way of comparing things.

Your ears and your other senses are by far the best judge.