Hello
I’ve been curious to see the difference in sounds in deleting either the rear pair or the middle set of mufflers. I’m not interested in straight piping my x300 (for numerous reasons mainly because it doesn’t sound great)

im trying to get a bit more of a low grumble/purr as I idle or cruise along, nothing super quiet like it is currently but nothing super obnoxious essentially.

If anyone has had any experience in doing both, either or even has a video/audio recording comparing either Would be greatly insightful.

Do you still have the factory system? I've found that meddling with the factory rear boxes is a near guarantee for droning while cruising. My XJR has had prior exhaust work where, at one point, there was a pair of aftermarket high-flow rear mufflers as the only silencing part of an otherwise straight-piped system, and it noticeably droned at part throttle. I replaced them with a pair of stock XJ8 mufflers from a junkyard, which bolted on without modification, and it's a definite sweet spot of civilized behavior when you want it but a nice growl when getting on it. This is a roundabout way of saying that the mid muffler delete is likely to be what you want if you're concerned about droning.

The mid mufflers are actually just resonators, they are straight through pipe. The rears are what does the main sound attenuation.

So would it be worth just removing the middle and keeping the rear? If it's just resonators... or the other way round?

resonators are primarily responsible for reducing drone.
hense partly why resonators are generally located under the cab as this is where the drone would be heard and needs to be elimnated.

from my experience with systems removing the middle muffle/resonator creates a drone and increases volume of sound but does not make much impact onto the pitch and depth of the sound.

i have not yet played around with the x300 exhaust,
but from playing around with the exhaust on other 4.0L I6 engines (ford barra) placing a straight pipe in place of the centre muffler creates a louder sound that creates a drone particularly under load at cruising idle around 1500-2000 rpm.

my guess for best sound would to be replace the centres with a free flowing hotdog style resonator to allow the sound to come through loud whilst eliminating the drone,
and replace the rears with a nice free flowing glass pak for a deep growl.

Just a comment ... this thread led me to look up "muffler vs resonator" on google to learn a little bit about exhaust systems and boy was that worthwhile.