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      05-30-2010, 11:46 PM   #1
jml's Avatar

Drives: E90M3
Join Date: Dec 2008
Location: Austin, TX

iTrader: (3)

Individual Audio sub crossover point

Have been meaning to do this for a while.

When upgrading to the SWS subs and a dedicated amp, I noticed that the SWS units had trouble playing over 120Hz. What I ended up with was a bit of a sonic hole between 100 and 200Hz.

To demonstrate this, in the plot below:

- Blue line: Pink Noise recorded with a calibrated RTA mic (ECM8000) from the stock system without subs, Mic is where my ears are in the driver's seat.
- Green line: overlayed on the line-outputs of the sub channels coming out of my 3Sixty with no processing (no EQ, no crossover, no subsonic).

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You can see that the sub channel is crossed over in the 225Hz realm, and the stock mids take over around 200Hz.

When I plug in the Amp and SWS subs, and add a 120Hz crossover (over which things start to sound like poo), and some EQing in both the head unit EQ and the 3Sixty, I get the plot below.

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You can see the gap between 100 and 200Hz, which is even more pronounced when you increase the sub volume relative to the OEM system.

The system does sound very good to me though, so I have no complaints. Male vocals and some instruments sound flat.

(Before I get flack on the accuracy issues of using an RTA to track frequency response in a car - the point of this is just to show high level observations on how well the SWS subs integrate with the OEM system.)

Last edited by jml; 05-31-2010 at 10:22 AM.
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