I put two of these in a 3" pvc pipe powered by a bluetooth amplifier rated at 2x50 watts. The pipe is approximately 27" long with 2 pieces of 1" pipe 6" long for ports and they sound really good. Very loud with really good bass. I get a lot of compliments and have already got requests to make some.
I've ordered several times from MCM and have always been very satisfied with their products, service and shipping.