I have a JL W3 15" sub. Right now I am running it off of an MTX 4-channel amp. Don't remember the size (I've had it for years ) and I'm running each voice coil bridged to one side of the amp (i.e. VC1 to Front left and right, VC2 to Rear left and right). Sounds good, hits decent.. but nowhere near it's full potential. I'd like to get something used of ebay to save my wallet a bit. Recommend a good brand and or size.. I'm more or less looking for size (wattage) then brand. I'd like to use the MTX amp for the mids and highs as I just got a crossover..so I'd like this to sound nice. K. Go.