SOUL | Drone Reduction Sound Symposer Delete
#16
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The valve to the sound symposer only opens when you press the exhaust button. I have the valve controller, and this is the data I recorded revving out the car to 8k on each setting
exhaust button off, valve controller disabled: 93DB
exhaust button off, valve controller enabled: 93DB
Exhaust button on, valve controller disabled: 96DB
Exhaust button on, valve controller enabled: 96 DB
Just turn the exhaust valve off, and the sound symposer is disabled. If the symposer plugged is quieter than just keeping the exhaust button closed, it'll probably be marginal.
exhaust button off, valve controller disabled: 93DB
exhaust button off, valve controller enabled: 93DB
Exhaust button on, valve controller disabled: 96DB
Exhaust button on, valve controller enabled: 96 DB
Just turn the exhaust valve off, and the sound symposer is disabled. If the symposer plugged is quieter than just keeping the exhaust button closed, it'll probably be marginal.
Last edited by IRM; 06-18-2021 at 05:11 AM.
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#18
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porscheflat6 (06-22-2021)
#19
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The valve to the sound symposer only opens when you press the exhaust button. I have the valve controller, and this is the data I recorded revving out the car to 8k on each setting
exhaust button off, valve controller disabled: 93DB
exhaust button off, valve controller enabled: 93DB
Exhaust button on, valve controller disabled: 96DB
Exhaust button on, valve controller enabled: 96 DB
Just turn the exhaust valve off, and the sound symposer is disabled. If the symposer plugged is quieter than just keeping the exhaust button closed, it'll probably be marginal.
exhaust button off, valve controller disabled: 93DB
exhaust button off, valve controller enabled: 93DB
Exhaust button on, valve controller disabled: 96DB
Exhaust button on, valve controller enabled: 96 DB
Just turn the exhaust valve off, and the sound symposer is disabled. If the symposer plugged is quieter than just keeping the exhaust button closed, it'll probably be marginal.
Very interesting. I have Cargraphic's valve controller - So if we keep the exhaust button off and valve controller forces the valves always open, do we have the best of both? i.e. Symposer is disabled and exhaust valves are open right? does the exhaust button on add anything on top re. exhaust sound? Thanks
Last edited by Merlotsj; 06-18-2021 at 08:08 AM.
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Soul Performance (06-18-2021)
#20
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^GeaTeaTrea: thanks for that info! Where did you place the recording device during your tests?
#21
Burning Brakes
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I wonder how this would sound with a race pipe now
#22
Three Wheelin'
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Of all the recordings I've heard of this engine I prefer the sound from the cabin interior so that's probably coming from the symposer and not the exhaust. I wouldn't bypass mine as I consider drone a non issue but might be interested in a symposer that's tuned a little sweeter.
#23
Burning Brakes
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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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#24
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The valve to the sound symposer only opens when you press the exhaust button. I have the valve controller, and this is the data I recorded revving out the car to 8k on each setting
exhaust button off, valve controller disabled: 93DB
exhaust button off, valve controller enabled: 93DB
Exhaust button on, valve controller disabled: 96DB
Exhaust button on, valve controller enabled: 96 DB
Just turn the exhaust valve off, and the sound symposer is disabled. If the symposer plugged is quieter than just keeping the exhaust button closed, it'll probably be marginal.
exhaust button off, valve controller disabled: 93DB
exhaust button off, valve controller enabled: 93DB
Exhaust button on, valve controller disabled: 96DB
Exhaust button on, valve controller enabled: 96 DB
Just turn the exhaust valve off, and the sound symposer is disabled. If the symposer plugged is quieter than just keeping the exhaust button closed, it'll probably be marginal.
#25
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Take my money! I was getting tired of this drone at 2200~2800rpm especially with the top up, and this rpm range is where your gears put you at the cruising speed mostly. Kline Exhaust + OAP sounds beautiful, but not at this rpm range...I intentionally have to use manual mode to keep the rpm range above 3k just to avoid this drone.
BTW, I have Soul Valve controller and it works like a charm with the best value compared to other products!
BTW, I have Soul Valve controller and it works like a charm with the best value compared to other products!
#26
Rennlist Member
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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 (06-19-2021)
#27
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Very interesting. I have Cargraphic's valve controller - So if we keep the exhaust button off and valve controller forces the valves always open, do we have the best of both? i.e. Symposer is disabled and exhaust valves are open right? does the exhaust button on add anything on top re. exhaust sound? Thanks
#28
RL Community Team
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I have found that I generally run the CG controller in Sport when I want all of the glorious sounds, and the Auto and leave the button in the console to off for the quietest running.
Still if pulling the tube and blocking the ends reduces the unwanted drone even more I will be doing this as soon as I find a pair of suitable plugs...
Still if pulling the tube and blocking the ends reduces the unwanted drone even more I will be doing this as soon as I find a pair of suitable plugs...
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#29
Burning Brakes
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Read in another forum there’s a 7.5 A fuse you can pull to shut off the symposer. Has anyone tried that and noticed a difference between that and plugging it up?
#30
Three Wheelin'
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Plugging the vacuum line for the Symposer and or keeping it's valve closed does remove much of the drone as mentioned above. However, even after doing that, the whole plastic tubing apparatus is still physically connected to the engine firewall. Even if plugged, it will still transmit some vibration and sound through into the cabin of the car.
When doing audiology testing on a patients at the doctors office, one can use a tuning fork to help determine a persons level of hearing. The doctor can rap the tuning fork and it will resonate for a while and its sound will slowly decay over time. When you put it near a patient's ear they can hear it for a certain length of time. If you then touch the end of the fork to the patient's mastoid bone just behind the ear, the sound will last a little longer and be a bit louder. This is because the sound is mechanically transmitted to the ear through the vibration of the skull and not just through the sound waves in the air.
So disabling the Symposer valve will help reduce the drone by inhibiting the transmission of the sound waves into the cabin. There will then be a further reduction in the vibration or resonance transmitted into the cabin if the Symposer is physically disconnected and removed. So everyone appears to be correct in their observations, and this should help explain why. So we have a good, better, and best type scenario here.
Look forward to John's OEM type parts to do the job.
When doing audiology testing on a patients at the doctors office, one can use a tuning fork to help determine a persons level of hearing. The doctor can rap the tuning fork and it will resonate for a while and its sound will slowly decay over time. When you put it near a patient's ear they can hear it for a certain length of time. If you then touch the end of the fork to the patient's mastoid bone just behind the ear, the sound will last a little longer and be a bit louder. This is because the sound is mechanically transmitted to the ear through the vibration of the skull and not just through the sound waves in the air.
So disabling the Symposer valve will help reduce the drone by inhibiting the transmission of the sound waves into the cabin. There will then be a further reduction in the vibration or resonance transmitted into the cabin if the Symposer is physically disconnected and removed. So everyone appears to be correct in their observations, and this should help explain why. So we have a good, better, and best type scenario here.
Look forward to John's OEM type parts to do the job.
Last edited by lovetoturn; 06-19-2021 at 12:04 PM.
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