A friend in an all girls band that I sub for when one or more of them is pregnant, is struggling with this underpowered 60 watt 112+T combo. Given my predilection for powered cabs, I thought a good solution would be for her to get an active sub (15" or 18" 600 watts or so) and run that in the FX loop of her combo using the high pass output into the return. My thinking is that the sub would get all the lows (depending on where she sets the X-over) and the combo would only have to deal with the mids and highs. She'd still be plugging into the input on the combo and using it's preamp and EQ facilities. Is there a better option? Budget is $600 max.