V6 3 mufflers?

I've got a 99 with a V-6, I'm curious about the apparent 3 mufflers in this setup? It goes headers, cat, muffler, then y into two more mufflers. Is that first one an actual muffler? If so what is the purpose of 3?  I'm wondering if i could do a single high-flow muffler in the first muffler's position and then just running pipe and split at the rear. Does this make sense? Thanks for the help.

it's a resonator, not a muffler. all honda V6 cars are "faux" dual exhasut since they combine into 1 cat and then split after the resonator into 2 tail pipes. a true dual exhaust car would have a "H" or "X" pipe, 1 cat/[precat for each side of the exhaust, 1 resonator for each side of the exhasut and 1 muffler for each side of the exhaust.