so.. Recently I purchased a crate amp that I LOVE!!! But its a 15inch speaker.. Dont get me wrong its loud and sounds great but I need to spread the sound around... Like I sound great in the pool house but we setup outside and I kinda fade out.... Like add another cab... I'm thinking 4x10 maybe not crate but I want sweet lows and great highs!!! Any ideas???

guild hartke 4/10 cabs sound very good,  they won't get real real loud but they have very clean ,full tones.  they won't get overly loud cause the speakers that they use don't have much flex (aluminum cones) they tend to distort out a a loud volume. 

if you want to get real loud and have great tone  get a svt 8/10 cab ,  they are very big, and a pain to move around, but great great sound.

Trace Elliot (sp) also makes a decent 4/10 box...Well they used to. not sure  what is going on with them recently.