I finally got around to uploading a sound clip of what my 5" straight pipe exhaust sounded like. My website also has clips for my original setup, Dynomax as well as 4" straight pipe.
My current setup, no clip yet, is the 5" straight with a 5"x18" Nelson Resonator. I put the resonator on in an attempt to reduce or remove the 2000 rpm drone as well as giving it the appearance of having a sound controlled device for inspection. Using a spectrum analyzer, I recorded data from before and after the install.
The results are as follows,
All measurements are at 10ft and done so with a Heath spectrum analyzer.
Idle 97-98 decibels.
98 db @ 180 Hz
96 db @ 45 Hz
The frequency range straight piped was 31. 5 Hz - 2. 8 kHz.
With Resonator,
Idle is now 97 decibels,
95 db @ 45 Hz
95 db @ 63 Hz
97 db @ 125 Hz
The frequency range with the resonator is 31. 5 Hz - 180 Hz.
website
This is a geocities website where bandwidth is limited so you may get a message that it is temporarily shut down so if anyone would like to mirror the clips or site, have at it.
Bob
My current setup, no clip yet, is the 5" straight with a 5"x18" Nelson Resonator. I put the resonator on in an attempt to reduce or remove the 2000 rpm drone as well as giving it the appearance of having a sound controlled device for inspection. Using a spectrum analyzer, I recorded data from before and after the install.
The results are as follows,
All measurements are at 10ft and done so with a Heath spectrum analyzer.
Idle 97-98 decibels.
98 db @ 180 Hz
96 db @ 45 Hz
The frequency range straight piped was 31. 5 Hz - 2. 8 kHz.
With Resonator,
Idle is now 97 decibels,
95 db @ 45 Hz
95 db @ 63 Hz
97 db @ 125 Hz
The frequency range with the resonator is 31. 5 Hz - 180 Hz.
website
This is a geocities website where bandwidth is limited so you may get a message that it is temporarily shut down so if anyone would like to mirror the clips or site, have at it.
Bob