I'm not entirely sure why a blueprint would be needed... unless you want to go overly in depth. *Generally, the idea is to just make a box that deadens the sound, the more basic the design, the better the likelyhood for sucess. *Even though a better wood choice would probably have lead to less external noise, I'm very happy with the functionality of my iso-cab. *I'd say it quiets the amp by 1/2... meaning by closing the door, what you actually hear outside the box is 1/2 as loud as the sound coming out of the amp. *Thicker wood, better materials, more foam... and you can silence it a LOT more. *I will rebuild mine one day, but for now this works well.
pics as promised... to rehas the 1st one, the dimensions are approx H:36" x W:36" x D:24"
EDIT - things I would do different. *Wood: change to 1/2" plywood/particle board (IE - car subwoofer box)... glue all seals as well as use screws... maybe a couple more inches of depth for more mic room (change from 24" to 26" or something that small).
(Edited by jay ratkowski at 12:56 am on Jan. 14, 2002)