I wonder what would it sound like if I replace the big chunky main muffler with a straight pipe but keep the smaller secondary muffler for stock look. Has anyone tried this setup? Sorry for

 

Well first of all you don't have two mufflers, you have a muffler and a resonator...

A resonator (Helmholtz Resonator) is chamber which is "tuned" to cut out a certain narrow frequency range, usually to eliminate a drone in a certain rpm band. Resonators, by inherent design usually offer no restrictions to the exhaust flow.

A muffler is an expansion or series of expansions (chambers) that reduces energy from the flow of gasses by expending it, thus reducing a much broader range of frequencies. Often, a muffler has "tuned" chambers which act to enhance certain frequencies while "muffling" other frequencies which enhances the exhaust note, but often at a cost of restriction.

Incidentally, the resonator was invented by Hermann Ludwig Ferdinand von Helmholtz, a German scientist who specialized in physiology, psychology, mathematics, physics, thermodynamics, chemistry, electrodynamics, ophthalmology and acoustics. He invented the ophthalmoscope, which is still in use today to examine the inside of the eye and was the first to measure the speed in which signals pass through the human nervous system.
He was generally regarded as the most intelligent man who ever lived until Albert Einstein came along...