3 Sundown 8's or 1 M5 MJ8M ?

[williambrea 10+ year member]

So if both setups would be ported, do the 8s have a similar output to the 18?

if the 18 is louder sealed then im sure that it will be louder ported, just because you go +3db's ported in theory, and you would have more air moving with the 18 anyway.