I don't think there is nothing wrong with prefab boxes if they are properly built, (like the ones linked) and if they have the recommended airspace. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif
I just bought a sealed prefab box not too long ago for a pair of w6s, and let me tell you it's built like a tank, yes I could have built it myself, but I got a good deal on it. But, before I bought it I properly measured and inspected it.//content.invisioncic.com/y282845/emoticons/cool.gif.3bcaf8f141236c00f8044d07150e34f7.gif
Now, a ported box is another story but you can estimate the tuning frequency if you have the port area and length.//content.invisioncic.com/y282845/emoticons/tongue.gif.6130eb82179565f6db8d26d6001dcd24.gif
Go for it!
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