Mine was back in the early 90's. I walked my happy ass to Wal-Mart,and bought some pioneer 6 1/2's...with my mowing funds.I made it to my friends house showed him what i bought,and told him i was going to make me a box for them....he told me there was some wood out back help yourself.I get out back and there was only one small sheet of plywood..its been rained on brown kinda nasty looking...lol i pull the 6 1/2's out the box,and lay them on the wood spread them out a lil..i take this pen and think to myself "This looks about right." and start marking my panels.I get everything cut out,and built the box,but on the ends of the box i left a ....i wanna say 2 inch gap at each end for the air to get out ..my idea of ports at the time.It did not sound to bad for no planning...just draw,cut,and build,but i had to put shirts in the gaps to seal it up...it sounded better that way...good times.!!!