SOUL | Drone Reduction Sound Symposer Delete
07-08-2021, 02:30 PM
#136
07-08-2021, 11:42 PM
#137
Three Wheelin'
07-08-2021, 11:59 PM
#138
I commented on the 2-3k bc that's where most people have been noticing drone, which also overlaps with highway cruising speeds. That said, although I don't usually find myself keeping the revs in the low 3k range (it's usually cruising speeds or redline, haha), I didn't notice any the few times I kept it there for a bit.
07-09-2021, 12:02 AM
#139
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After following this thread it seems that a lot of this is not necessary - can I assume I can just plug the hole on the exit tube into the cockpit on the passenger's side?
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07-09-2021, 01:13 AM
#140
07-09-2021, 02:06 AM
#141
Three Wheelin'
07-09-2021, 08:13 AM
#142
Different people have different setups and level of tolerances. The original customer Soul worked with seemed to have very low tolerance for drone/boom with only an OAP. I had to get into the engine bay anyway to install the valve controller so I figured I might as well plug everything up.
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Paulywanacracker (09-10-2021)
07-09-2021, 08:18 AM
#143
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I thought I read that disconnecting the vacuum line leaves the valve closed, which effectively "plugs" up the unit also, no?
07-09-2021, 02:29 PM
#144
RL Community Team
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TBH, there's no harm in trying, and if you find it insufficient, then open up the engine bay and plug everything up.
Different people have different setups and level of tolerances. The original customer Soul worked with seemed to have very low tolerance for drone/boom with only an OAP. I had to get into the engine bay anyway to install the valve controller so I figured I might as well plug everything up.
Different people have different setups and level of tolerances. The original customer Soul worked with seemed to have very low tolerance for drone/boom with only an OAP. I had to get into the engine bay anyway to install the valve controller so I figured I might as well plug everything up.
Oh, and for me, getting to the engine is easier than pulling apart the interior and possibly breaking clips there...
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Paulywanacracker (09-10-2021)
07-10-2021, 12:23 PM
#145
I unplugged the vacuum line to the symposer with Soul's Resonated Race Exhaust - it went from nearly unbearable drone and booming in the 2000-2800rpm range to a pretty livable loudness in the 2200-2600rpm range.
Probably close to 50% reduction just unplugging the line.
Probably close to 50% reduction just unplugging the line.
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Goodwood (07-10-2021)
07-10-2021, 04:54 PM
#146
Seems like shoving some sound deadening material into the tube from pax compartment followed with a noise canceling foam foam (like a compressible ear plug) would achieve a majority of the effect.
07-10-2021, 05:04 PM
#147
Perhaps plugging the tube with some cork and then sealing it with silicone gel? Seems that would create a great sound stopper.
07-10-2021, 05:08 PM
#148
07-10-2021, 06:24 PM
#149
Rennlist Member
OMG. Well I can hardly believe it! This mod really works to cut down the resonance/boom/drone and overall interior negative sounds. I have the Cargraphic Valve Controller, Kline Inconel OAP and rear on my GT4 w/PDK. I did not think the car was much louder with the Kline vs the OEM exhaust, but the car is 'loud' inside no matter what - my issue with stock was the quality of the sound along the rev range and especially above 6,000 rpm. So much so that I would drive with the windows down to not have so much interior noise and, on occasion, I would take to putting in ear plugs! Now with the entire sound symposer pulled out and the fire wall hole plugged with 80 mm Dynamat the interior is much quieter over all. The drone ranges still exist but as others have said, the 'noise' is cut in half (about like having the ear plugs in!). I have to drive a bit more to see if at higher revs the car still satisfies. I think though overall its an improvement in livability, especially since wife's (and to a lesser extent mine) major complaint was the drone/loud interior. Ill update in a bit after a longer test run. I used a regular 1" drain plug and the methods of removal described above. Big thanks to John @Soul Performance and everyone else who commented on this mod - I think well worth it if your are sensitive to the interior sounds of this car.
PS. One other note... I did use some of the extra Dynamat to cover the both the engine cover and the firewall behind the seats since I was there anyway. I did this to maximize my returns on taking the car apart again (3rd time!). I dont know how much this helped with noise cancellation but probably some....
PSS. Yes I recognize the contradictions here perhaps to some extent of going to an after market exhaust and then quieting the interior... but its really about sound quality and when the sound is heard along the rev range. I think if John and his crew are exploring this with their mission being towards performance, then I think its safe to say we are in good company!
PS. One other note... I did use some of the extra Dynamat to cover the both the engine cover and the firewall behind the seats since I was there anyway. I did this to maximize my returns on taking the car apart again (3rd time!). I dont know how much this helped with noise cancellation but probably some....
PSS. Yes I recognize the contradictions here perhaps to some extent of going to an after market exhaust and then quieting the interior... but its really about sound quality and when the sound is heard along the rev range. I think if John and his crew are exploring this with their mission being towards performance, then I think its safe to say we are in good company!
Last edited by dnimi123; 07-11-2021 at 12:04 AM.
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07-10-2021, 08:25 PM
#150
Racer
PSS. Yes I recognize the contradictions here perhaps to some of going to an after market exhaust and then quieting the interior... but its really about sound quality and when the sound is heard along the rev range. I think if John and his crew are exploring this with their mission being towards performance, then I think its safe to say we are in good company!
This sound pipe an example of when "over-engineering" for no good reason happens. Good thing there is a relatively simple solution for it.