[quote name='BigRedX' timestamp='1438950758' post='2838921']
My big concern with the lightweight cabs is that it appears to be very easy to end up with a rig that is top-heavy. My current big rack weighs 28Kg and I expect the small rack to be around half of that by the time it's fully loaded with all the gear, and therefore I'm a bit concerned that when it's stacked on top of two small cabs whose combined weight is about the same as the rack it's going to be unstable.
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What you need to consider is how far the stack would need to rock to put the CoG of the whole lot outside the footprint of the bottom cab, as that's when it would topple. A couple of 1x12s around the size of the Berg CN112 or AE112 form a stack similar to a lightweight 4x10 in size and weight. Are you using a 4U rack at the moment? What's the weight distribution like in it - even, bottom-heavy, top-heavy?
As for actual recommendations - I'm very happy with my combination of Tecamp Puma 900 and two Berg AE112s. If there's another Nottingham Bass Bash, I'll bring them up .