i am wanting to convert my Carvin RL115 cab into a 2x12 or maybe a 2x10. i measured it and the inner dimensions equal 6048 cubic inches. this does not include the bottom slot port. i can make this smaller if i had to (by trimming off the back or from the bottom or sides). i am going to buy a piece of ply for the front (for the new speakers) question, how do you compare cubic inches or feet, to liters From the Eminence Website - Omega 12 Recommended Enclosure Volume - 34 - 57 liters (vented) 1.2 - 2.0 cu. ft So how do i convert this? this is not the speaker im definitely going to use, im actually looking still. how do i determine the size port i need? i know i may not know much about speaker cab building, but anything else i need to consider. any good links for some information? this a project i really would like to do. thanks for any help you may give.