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SQ Box Ideas

Post all your general car audio questions here.
Jonathan
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Joined: Sun Jan 09, 2005 5:44 pm
Location: Georgia

Post by Jonathan »

Group delay is related to transient response, how well the sub can track the input signal. A low group delay indicates good transient response. Good part is, assuming it was audible, this would be "tighter" sounding bass. At least to the BS slinging golden ears, anyway. This is usually far below the limits of audibility, but this alignment does give lower bass and has a lower Fsc. Impedance peak can tend to be higher, though. Keep in mind any time you use equalization to flatten the frequency response of a subwoofer, you add phase shifts in that region, which eliminates the benefit of a good group delay.

Flat FR you already know the benefits of. This is anechoic, though, not a car environment with resulting cabin gain. Due to cabin gain, you will likely have peaks and dips in the frequency response due to this, and you go back to the equalizer reference.

You'll see that on most of JLs enclosure recommendations, the Qtc of the subs differ according to the sub used and it's characteristics. In my experience with their subs, these recommendations do a pretty good job of providing a relatively flat FR in the average vehicle, but of course nothing is perfect. The best thing you could do is get an RTA and look at the effects your car has on the system response, comparing that with what the sub would have in a predictable environment. From there, you could decide upon an enclosure size and type based upon the car you're using, in which the ideal enclosure could be smaller or larger depending on the characteristics of the environment. Not really something I or anyone on the forum could help you with, not specifically anyway.
Ryan from Ohio
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Joined: Fri Mar 17, 2000 12:00 pm
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Post by Ryan from Ohio »

Looks like you got your car all dirts and grit on the stuff you are painting behind you?

lol

not good!
-Ryan
www.caraudiocentral.net - Your #1 Car Audio Resource on the Net!
JeremyC
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Posts: 2329
Joined: Sat Jan 15, 2005 4:13 am
Location: Oklahoma

Post by JeremyC »

To bad thats my neighbors car. (you thought I would do that to the accord)

And its just dust, no paint. I did all the paint work in the other room.

Oh yeah the pic was after the fact. We had already cleaned up, and moved the painted stuff in to finish drying. The only reason I put the mask back on was for the pic.

Jonathon thanks for the info. Guess I will have to put the sub box on hold for a few weeks. Right now all I have is the eclipse's pink noise sweep to work with, and its not all that accurate and only picks up from 60 or so up. Guess I will have to get a mic, and download an RTA setup for my laptop. I know we covered that a few months ago, anyone remember the link?
JeremyC
Master of My Domain
Posts: 2329
Joined: Sat Jan 15, 2005 4:13 am
Location: Oklahoma

Post by JeremyC »

Well I just figured it up and right now my box is 1.375 JL specs

according to WINISD a flat responce would be 2.29

and a flat delay would be 6.8

So a flat delay is out of the question. At the most I can due 3 to 3.5 cubes. Which puts the slope right between the two.
JeremyC
Master of My Domain
Posts: 2329
Joined: Sat Jan 15, 2005 4:13 am
Location: Oklahoma

Post by JeremyC »

Does anyone want to build me these. To bad they won't fit my accord. Anyways. If anyone has any ideas or pics of an 03 to 06 accord with kickpanels let me know. It looks like that will be my next project before I finish the sub box.
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