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- United States
Someone earlier posted one of my Subaru videos (Blitz exhaust on a 05 WRX). I wanted to step in and correct something.
The audio is being recorded in that video approximately 18 - 24" from the muffler, not in the same location as the GoPro. It was also recorded with a good lav mic powered via a recorder, which allows me to adjust the sensitivity as I listen to it via a decent pair of headphones in the passenger seat.
Here are some more videos for discussion purposes. Listen at 720p to get a wider range of frequencies.
Go to about the 00:50 mark. Mic is located under the hood.
This is a recording from my STI with an aftermarket intake setup and exhaust. The mic is in the airbox, hence the low frequency sound overrunning the high frequency / velocity "turbo sound."
This is recorded from the engine bay. The prominent sound is the externally vented wastegate. The fluttering is from the boost control setup rapidly adjusting and due to the oversized wastegate diameter. When the car gets sufficient load the sound smooths out because of the wastegate duty.
Here's my car again (11' STI) from the inside. I believe I used the GoPro mic for one or both of these videos, but you get the idea. It also shows the difference in engine power output between ambient temperatures.
It should be stated that the Subaru sound that people keep talking about is actually the sound generated by uneven exhaust pulses from the unequal length exhaust manifold. Not all Subarus have these, including the Subaru STI the Japanese team would have modeled the Subaru sound from, which uses a twin-scroll equal length exhaust manifold. The car in this video uses a single-scroll 4:1 equal length exhaust manifold. Notice the "rumble" is gone.
This is my car with the stock unequal length exhaust manifold. Notice the sound difference.
Learn more about this here: http://www.vikingspeedshop.com/equal-length-vs-unequal-length-subaru-exhaust-manifolds/
The audio is being recorded in that video approximately 18 - 24" from the muffler, not in the same location as the GoPro. It was also recorded with a good lav mic powered via a recorder, which allows me to adjust the sensitivity as I listen to it via a decent pair of headphones in the passenger seat.
Here are some more videos for discussion purposes. Listen at 720p to get a wider range of frequencies.
Go to about the 00:50 mark. Mic is located under the hood.
This is a recording from my STI with an aftermarket intake setup and exhaust. The mic is in the airbox, hence the low frequency sound overrunning the high frequency / velocity "turbo sound."
This is recorded from the engine bay. The prominent sound is the externally vented wastegate. The fluttering is from the boost control setup rapidly adjusting and due to the oversized wastegate diameter. When the car gets sufficient load the sound smooths out because of the wastegate duty.
Here's my car again (11' STI) from the inside. I believe I used the GoPro mic for one or both of these videos, but you get the idea. It also shows the difference in engine power output between ambient temperatures.
It should be stated that the Subaru sound that people keep talking about is actually the sound generated by uneven exhaust pulses from the unequal length exhaust manifold. Not all Subarus have these, including the Subaru STI the Japanese team would have modeled the Subaru sound from, which uses a twin-scroll equal length exhaust manifold. The car in this video uses a single-scroll 4:1 equal length exhaust manifold. Notice the "rumble" is gone.
This is my car with the stock unequal length exhaust manifold. Notice the sound difference.
Learn more about this here: http://www.vikingspeedshop.com/equal-length-vs-unequal-length-subaru-exhaust-manifolds/