Spoke at length with an old MOPAR expert (Norm Brandies owner of Westech) about the sound of the SRT 10. He has lots of Viper wrenching experience and has owned several.
He said that the position of the muffler is critical to sound and resonance.
He went into a long discussion (that I started to recall from physics classes) about the sound wave amplitude and frequency emitted from the engine. His experience is that if the middle of the muffler is at the maximum amplitude of the sound wave proceeding down the exhaust system, that is the optimum way to manage sound and resonance. The factory does this routinely as a part of the engineering process. But when we modify the engines, and the exhaust system we do not do the sound engineering step.
Anything that changes the amplitude or frequency that emit from the engine will probably alter the optimum placement of the muffler. Certainly major changes like cams, head work, etc. will alter the sound wave and consequently optimum muffler placement. Headers and cat delete become alterations that change the frequency and amplitude of the sound wave too.
This may be why so many of us have different experiences with the sound satisfaction of our exhaust systems...every vehicle with modifications will react differently...even with the same muffler.
I worked on my sound all winter and spent a lot of money getting it right, but Norm believes that much of the time it is just luck that determines sound...unless you are a sound engineer and have the instruments to do the correct analysis. Two inches can make the difference...and when we alter our exhaust systems...who takes the time to determine the frequency and amplitude of the the sound wave?
This probably does not help, but it may give you some perspective on the search for the right sound and the elimination of that infernal buzz in the cab!
