Sorry, can't tell you exactly how it will sound. Have you considered just removing the stock resonator? It will give you a slightly lower pitched idle, and will not be much louder than stock under regular load, but when you punch it and the engine growls, the exhaust really opens up and purrrrs (it will be kinda loud and lower pitched).
I'm guessing the Super Spring resonator will have a similar effect on pitch and volume, but can't say for sure.
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