The stock one is very quiet, until you get up in the rev range then it has a little bit of a bark.
I have the Akrapovic from an RT Triple, it has a very nice tone, a little deeper than the straight shot,
and it is also longer, so the noise leaves the muffler closer to the rear of the Spyder.
Not a great pic below, but you should be able to see the difference in length.
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