sub box, use manufacturer specs or my own
Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=89919
Printed Date: April 28, 2024 at 4:07 PM
Topic: sub box, use manufacturer specs or my own
Posted By: goser
Subject: sub box, use manufacturer specs or my own
Date Posted: February 01, 2007 at 11:44 PM
I'm building a sealed box for a infinity perfect 12.1 (running off infinity 611a) and I see most people on the forum are using a 1 cubic foot box, which is what the manufacturer recommends. However, using several calculators to get a qtc of .707 the box should be 1.6 cubic feet. What would be the differences between these two boxes?
Replies:
Posted By: stevdart
Date Posted: February 02, 2007 at 8:40 AM
0.6 cubic feet. I love pop quizzes. ------------- Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.
Posted By: goser
Date Posted: February 02, 2007 at 8:43 AM
Took me a second to get that... Anyone else?
Posted By: jettagli03
Date Posted: February 02, 2007 at 10:22 AM
Haha, I would listen to him.
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Posted By: Steven Kephart
Date Posted: February 02, 2007 at 10:28 AM
Factory recommended enclosures are purely a recommendation that provides a specific marketed response from the speakers. I'd recommend using the enclosure size that works best for your install and listening tastes. Also, don't be locked on .707 as "ideal". It provides a maximally flat anechoic response, but might not work well in a vehicle when cabin gain is added. As for the differences, the 1.6 cubic foot enclosure will have more low end and be more efficient, but at the cost of power handling.
Posted By: kirktcashalini
Date Posted: February 02, 2007 at 11:40 AM
mine are 1.05 and the qtc is around .752, sounds rockin, all types of music sound great to me. I just manually adjust the bass if I am listening to rock, pop, rap, etc... to my likings, and am VERY happy with it at 1.05
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99 Blazer LT. Yellow Top. Big 3. Infinity Kappa Speakers All Around. Jensen CD/DVD flip out. 2 Infinity Kappa Perfect 12DVQs powered by a Alpine PDX600.1 (in one custom box, building a FG box)
Posted By: j_darling2007
Date Posted: February 02, 2007 at 12:53 PM
I have 2 12.1 kappa perfects running on the 611a amp and I just took them out of their 1 cubic foot boxes and put them in 1.8 cubic foot sealed boxes. It has a little more output and it still sounds nice and clean
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There are 3 kinds of people in the world, those who can count and those who can't
Posted By: kirktcashalini
Date Posted: February 02, 2007 at 11:05 PM
From what I have heard from numerous people is that they are pretty accepting subwoofers, and will sound good in most applications, jdarling is a perfect example, he is almost doubling the box size, that just shows the acceptiveness of these subs to almost any type of box heh.
bottom line... enjoy!
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99 Blazer LT. Yellow Top. Big 3. Infinity Kappa Speakers All Around. Jensen CD/DVD flip out. 2 Infinity Kappa Perfect 12DVQs powered by a Alpine PDX600.1 (in one custom box, building a FG box)
Posted By: goser
Date Posted: February 03, 2007 at 11:08 AM
Hmmm... Ideally I want the flattest, lowest curve, but space is at a premium. I think I'll go with the factory recommendations, solely for the size. I just found out I might be able to get my hands on some free fiberglassed marine grade plywood--if I do I'll build both boxes and post back. Curious though, could you clarify how the larger enclosure would affect power handling? If i figure right, the more air space the less resistance therefore higher efficiency but requires more power?
Posted By: Steven Kephart
Date Posted: February 03, 2007 at 11:44 AM
goser] wrote:
p>Curious though, could you clarify how the larger enclosure would affect power handling? If i figure right, the more air space the less resistance therefore higher efficiency but requires more power?
The larger enclosure takes less power to reach a given amount of output because of the increased efficiency. But the speaker will reach it's mechanical limits earlier in the larger enclosure, thereby decreasing it's power handling.
Posted By: roo-dog
Date Posted: February 11, 2007 at 9:23 PM
-s.k.'s right. I used to always opt for a little larger than recommended box size; to get those real low frequency notes, which always worked, but couldn't put as much power to them. now, i really like to thump it hard sometimes, so i stick closer to mfgr's recommendations. if it's not low enough, i just stuff it with some poly-fill, and that usually brings back the full sound. also, if i am building box for myself or a good friend (not just a job), i always line the box with several layers if fiberglass- hits so much harder. that plywood might work good, too. i have also built boxes with 1/2" mdf, then threw 3-4 layers of fiberglass on the inside, they were rock-solid.
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(4)g5-1244, (4)gtr12, (2)ppipcx2400, (1)pcx4125, (1)pc4800.2, (3) pair mb quart 6.5"Q, (4)optimas, alumapro (1)5 and(1)15 farad cap, premier deh-p860mp, pioneer xm -dual H.O. alternators
Posted By: mumbling rednec
Date Posted: February 14, 2007 at 3:04 PM
Okay I got a question about the air space for speakers when it says that the air space recommened is .8 - 1.5 cubic feet for the speakers is it better to get a box that has .8 air space or something close to it or 1.5 air space. Also how would you calculate the qct of a speaker box becasue I have two infinity kappa 12.1 in my truck with a box that has 1.4 cubic feet but they rated for 1.0 cubic feet should I down size my box to where the air space is closer the the recommended.
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Ryan Mertz
Posted By: aznboi3644
Date Posted: February 14, 2007 at 4:46 PM
bigger the box the better low end response at the cost of power handling. Smaller box the tighter the bass and higher power handling. You can enter your box into WinISD and it will tell you what qtc it is
Posted By: mumbling rednec
Date Posted: February 14, 2007 at 4:54 PM
winISD what is that and where is it ------------- Ryan Mertz
Posted By: aznboi3644
Date Posted: February 14, 2007 at 5:31 PM
Read the stickey...it is free and easy to use
https://www.the12volt.com/installbay/forum_posts.asp?tid=74558&PN=1
Posted By: goser
Date Posted: February 15, 2007 at 7:24 PM
I found UniBox407 easy to use. Can't remember where I got it tho
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