Muffler Testing, etc.
My mufflers have readings very similar to this; all from 10 feet from the tailpipe's tips.
Quiet Loud
Idle 68 dBA 78 dBA
2200 81.5 dBA 92.5 dBA
3500 88 dBA 99 dBA.
Air flow is right around stock when quiet at ~ 40% of a straight pipe and in the same level as typical two chamber, 2.5", offset-offset, chambered mufflers at 55% of an open straight pipe when in the open mode. For comparison, "good" mufflers will flow 75 to 105% of a typical muffler-length straight pipe. These VOE's are not performance mufflers as such as just way cool to drive around with.
Tom