East87

It seems like the SS (or any supercharger's) whine behaves like an emergency vehicle's siren. Higher frequencies of sound are more noticeably affected by distortion in movement which could explain why your statement above makes perfect sense.

The reason such high frequencies are used in sirens is because:
1. The receptors in the coiled human inner ear for high-frequency sound are located closest to the ear canal opening, thus we most easily hear higher frequencies and are more likely to be startled or react to sudden high-frequency noise.
2. Higher-frequency sound waves do not travel as far or maintain their energy for as long a period of time as low-frequency sound waves through any medium (solid, liquid, or gas).
3. High-frequency sound waves decompress as the moving object from which the noise is originating moves away from an outside stationary observer. This decompression rate is much higher in high-frequency sound than in low-frequency sound which explains why you can hear a loud exhaust for a longer period of time at a longer distance, whether it's coming at you or moving away from you. How awful would it be for us to be able to hear any emergency vehicle siren within a few miles at all hours of the day/night? Tornado/disaster warning sirens blend high and low frequencies together to achieve a desired balance between distance the sound is capable of traveling and "attention-grabbing-ness".

The whine frequency is shifted into a higher range due to the speed of an oncoming vehicle, but the noise is not as strong or almost undetectable as the car is driving away from an outside, stationary observer. Because the frequency of the sound is really only elevated due to oncoming speed, the frequency from inside the car will not be as high either. It doesn't help the cause that the blower is situated underneath the manifold assembly...which is then separated by a metal hood, either. Don't forget the wind rushing over the vehicle body (which any driver is acutely aware of while traveling at speeds generated by the added power of a blower) which can also override some of the frequency range of the supercharger whine. Additionally, the rumble from your exhaust is most likely drowning out a lot of the whine inside the cabin.

I was in my friend's Whippled GT a few weeks ago. He's running 10.5-11lbs of boost which makes for some incredible whine. However, I could barely make out the sound of the whine while we were on the highway, and believe me, he was opening it up as much as he could. I'm sure to a stationary observer, that thing would have been positively screaming, but I just don't think you can get the volume of whine inside the cabin that you can hear due to the compression of the sound waves as experienced by a stationary observer outside the vehicle. Between the lack of compression, wind, and loud exhaust, there is great difficulty in hearing that glorious whine from inside the car. Do yourself a favor and have a trusted friend or family member go WOT as you're standing by the side of the road. The sound will literally MELT YOUR FACE OFF.

shoeys08dkcandygt

looks great and sounds mean. congrats on the install. wish i had the $$$ to drop on a kb right now. enjoy the new found power buddy. and yes!!! respect her. lol

kpaulhus

Bob....you have inspired me to get my next mod before Christmas.