I played on a river cruise boat and there were about 50-60 epople on the top deck with me. I used a Kustom KM100 amp (100 watts into a 15" and tweeter). It covered the crowd very well, but my wife said it got considerably quieter toward the back.

I still can't figure out you how some of you guys use Logitechs; it seems to me that coverage and saturation would be less than 100 watts and a 15" speaker. BTW, I was using my 2k, a SC88 and a mic.