im not sure of the exact size but i think its just a little bigger than mids, i put my speakers that were in my door in there and then bought a new set for the doors then hooked it up to a 3500watt 4 channel amp and 2x 10" subs behind the seats on a 5000watt monoblock.
you going to need a little bit of bass atleast because those speakers hurt your ears when the volume is turned up lol
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Current2008 Opel Corsa C UTE 1.4i
2x Pioneer Champion Series 10" DVC's
1x XTC 5000watt Monoblock
123db
2000 Opel Corsa B 1.4i
EX1997 VW Citi Golf (1.6i Polo Conversion)
1991 VW Citi Golf 1.3