I did build myself two Thiele cabinets with EVM12L in 2011 - and later i added a tweeter and Eminence crossover.
Included also a switch to be able to switch tweeter (and crossover) off and just use the EVM12L (with cab sim off)
I did this witthout doing any calculations and i must admit i have not used the cabinet much lately. Mostly i play with headphones
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