View Full Version : qtc vs. manufacturer

12-25-2005, 01:14 AM
I see a lot of boxes that exceed the recommended volume from the manufacturer, and I was wondering whether or not doing so will damage the sub at all? The reason why I'm asking is that the Kicker manual states not to build a box with internal space exceeding the recommended. Thus it is impossible for me to adapt the box to reach a .707 qtc for my 12" Kicker Solo-Baric L5.

Qtc = .707
Qts = .566
Vas = 2.41 ft^3

yielding a Vb of approx. 4.30 ft^3, while the recommended maximum volume from Kicker is 2.0 ft^3.

Since I'm going to build one of my buddies's boxes for him I would like to know whether or not I should go with the maximum recommended or ignore the number from the manufacturer and go for a qtc of approx. 0.707

12-25-2005, 01:29 AM
Two things:

1) Manufacturer's typically "recommend" enclosures on the smaller side (higher Qtc) as it gives the sub that "tight, punchy, warm" sound that most street-beaters are after. It's a good, "marketable" enclosure that salesman like and that most street beaters will like.

2) You will never damage a sub by going with a larger enclosure given you take into account that mechanical power handling will decrease as enclosure size increases. You can run any subwoofer on the planet in an infinite baffle arrangement (i.e. no enclosure at all) and not damage it, as long as you realize and take into account that mechanical power handling is DRASTICALLY reduced. That and the resulting sound might not be too pleasant IB for certain subs....but my point was that larger enclosures won't damage a sub as long as you properly reduce the power the sub is receiving accordingly.

Now....all that said; Best thing to do is play around and see what you think. If possible, build two enclosures....one to manufacturer recommendation and one to your own calculated specs and see which you prefer. Or, build one enclosure to the larger of the two specs (in your case, 4.3cuft) and use spare wood or the like to fill the enclosure to the smaller recommendation and see which you prefer.

I don't know much about that Kicker off hand, otherwise I'd give you some better guidance...but the above is some general info and some generally good trial-and-error.

Also gives you some good first hand listening experience of how the enclosures can affect the sound of a subwoofer :)