Originally Posted by noah katz
That's certainly the simplest way but not optimum because it doesn't account for the different freq resp of each sub and their acoustic interaction; see Geddes et al mult-sub approaches.
It is optimum, if you do the Geddes et al methods prior to applying EQ then less EQ is needed. EQ should be the last solution, setting up the subs properly before EQ is the best solution.
The different frequency responses of each sub will interact with each other once they are playing the same signal, why then would you want to play a separate signal to each sub and apply different EQ settings? If you have a peak at 50hz with one sub you know that with placement and phase (delay) with another sub can counteract that peak. If you were to apply EQ to that first sub without checking how both subs play together you will be adding an unnecessary cut at 50hz to only 1 sub if the other sub counter acts that 50hz peak.
All the subs are playing the same signal and we are trying to get the flattest response at the MLP, EQing the subs as one is the proper way to do it. The only reason to EQ each sub separately is if they are playing a different signal, like a stereo left and right sub. It is called 5.1 for a reason, there are 5 discreet channels and single LFE channel as it plays the same signal.