I'm new to talkbass and have a question on cabinet ports. I'm building a single 12 cab 14h x 17.5w x 15d.(inside dimensions). Basically close to the same size as Aguilar gs 112.How many and what dia. and length of the tube if any would work best? I'm thinking 2-3" ones?? I'm using a Eminence 12LFA speaker. By the way the cab is made of 3/4 plywood. Thanks for any info!