I'm looking at building a 2-18" compact sub pretty much exactly like a now defunct Carvin trx2218b. I heard this sub and it is unbelievable how much low end it puts out compared to a proline JBL for example. I can see pics and cabinet dimensions for the cabinet but no info on how deep the ports are. kinda need that to be right. I can still buy those same speakers but I hesitate to buy something like that now knowing who the real manufacturer is in case I need replacements in the future. I'm leaning to go with Eminence speakers just to future proof the cabinet. any ideas on how I should proceed?