I put the Double Up System on my Wakesetter at the beginning of last summer and I couldn't be more satisfied. They are plenty loud enough to be heard 80ft behind the boat. Now im sure the Threesome is so much louder but i choose sound quality in stead of just straight loud. The one thing I love about the double up package is the MB-80's because they help add the mid-bass and a much fuller sound. As far as amps go im running the Kicker ZX850.4 and it has more than enough power. Overall they are great speakers and compared to the fusion 3 way that I had before my wetsounds, the wetsounds blow them out the water.