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Discussion Starter #1
Hi all,

Since I'm going to go with a ported setup, I can design my boxes to port directly through my rear deck and fire straight up towards my rear window or I can just keep the box in the trunk like a regular box and have them fire directly backward. Is it better to route the ports directly into your listening space? My car has a back seat, so the ports would be firing up about 3 feet behind my head I guess........
 

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xencloud said:
Hi all,

Since I'm going to go with a ported setup, I can design my boxes to port directly through my rear deck and fire straight up towards my rear window or I can just keep the box in the trunk like a regular box and have them fire directly backward. Is it better to route the ports directly into your listening space? My car has a back seat, so the ports would be firing up about 3 feet behind my head I guess........
Since the ports are designed to a specific resonant frequency, I would think that you would have a huge bump in response at the tuning frequency of the port.

The overall setup would probably perform more like a bandpass enclosure than a conventional ported box; the output of the sub will be attenuated by its location in the trunk, and you'll have the full output of the port at its tuning frequency firing into the cabin. If this sounds good to you, go for it. It's probably not the route to SQ, though.
 

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Discussion Starter #3
Could you improve this by tuning the box very low, say 25hz or something? Also, couldn't you flatten out the response with an EQ?
 

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xencloud said:
Could you improve this by tuning the box very low, say 25hz or something? Also, couldn't you flatten out the response with an EQ?
Well if you tune the box below the resonant frequency (Fs) of the sub, the driver will bottom out.

But I think the problem is this; this woofer's cone is going to be isolated from cabin, and the enclosure's port is going to fire directly into the cabin. This is going to mean that, regardless of the frequency that the port is tuned to, the output from the port is going to be, relatively, much louder than the the output of the woofer from the listening position.

As a result, you are going to get a very loud bandpass effect at the tuning frequency, and the rest of the woofer's output will be attenuated.

To compare; with a ported box in your trunk, both the woofer's output and the output of the port are going to be attenuated by the same degree (as a result of being in the trunk) so the overall output from the system is going to sound balanced. Same with a ported box in the back of a station wagon or hatch.

I doubt that you'd be able to improve things much with EQ.
 

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tbreihan said:
Well if you tune the box below the resonant frequency (Fs) of the sub, the driver will bottom out.
no.
 

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Discussion Starter #6
Well, I see what you're saying about the two sounds not being able to blend together, I guess I'll just fire them normally toward the trunk. Easier to build the box that way anyway........ :cool:
 

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Derek said:
Glad you said that. Can you explain though why that's the case? I know it to be true, but I don't know why.
 
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