Can one upgrade bass drivers at a later date?

Hi Wayne,

I am another person interested in using your speakers as a low-frequency box for the Oris Lowther horns, so I am primarily interested in the frequency range or 300 Hz on down. I am particularly interested in the four pi's and 7 pi corner horns. I notice your dimensions for the various series vary a bit. Could I, for example, initially purchase or build a 4 pi or 7 pi, and then upgrade bass drivers as funds become available? Would that result in an incorrect alignment due to box dimensions and port loading? Or could I request a set optimized for the driver I will eventually want, and use the "wrong" driver initially until funds become available?

Thanks for any information,
John

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