That first one is the mid muffler. Replacing it with an X-Pipe with everything else stock behind it changes next to nothing. I didn't notice a difference after replacing my mid with the X after the baffles broke loose inside the muffler. It does function as a pulse equalizer.
Right behind there are resonators to cancel out drone that the muffler behind and in front didn't handle. Just your typical (but stock) bottle style resonators. I'm not sure what the internals look like...
The mufflers in the back are huge and are quite good at muffling the sound to "Average Driver" levels.
So it's a mid muffler followed by a resonator on each pipe, and then the rear mufflers to complete the catback.
'09 PSM G8 GT - OPG Intake, DOD-Delete w/ Stage 1C 218/229 .600 Lift 117.5LSA, Kooks 1 7/8 Mids, Solo Axle-Back w/ X-Pipe, SuperPro Bushings (Front and Rear). BMR Sway Bars (Red)
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