sub box does not matter

There is a lot of info on enclosures on this site. Here is a link on the types and how to calculate them Now as far as your friend. . . The enclosure type and size will either make or break the subwoofer. Here is a simple way to look at it. As you move on to more expensive and quality brands a custom enclosure is a must. You cannot buy a $600 Fi Audio BTL and spend 40 bucks on a prefabricated box. This will almost guarantee that your $600 woofer won't sound any better that a 80 dollar kicker.

Along with the above, your friend's education should continue with a reading of What Is A Proper Sub Box.  Then, browse through the subjects fielded by the author forbidden.  You'll get a good sense of how important the enclosure is.

The search tool found  here yields tons of information.

Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

simply put the cheapest sub in the perfect box will outperform the most expensive sub in the complete wrong box.Kevin Pierson

a simple example is how even a 10 or even an 8 can theoretically be louder than a 12. which tells you that there is more going on in a system than just how many subs on so many watts that make any given system as loud or not loud as it is. ill give you my personal example, i have an 18" RE audio SX in my extended can ford ranger. the first box i built for it was roughly the same size as the second one i built and still have to this day. with the first box i could barely eek out a 143 on a DB meter, which is pitiful. so i rebuilt the box and changed the tuning of the port and added about 0.5ft^3 to the overall volume and wow what a difference! i instantly gained about 6-7 DB off of the same sub with the same power going to it in the same truck, the only thing changed was the box. and it's not just about loudness either, a poor box can completely ruin the audio quality you get from your sub too. another personal example, i used to have an jl audio 8w7, arguably one of the best sound quality 8 inch sub on the market. the first box i built for it was a sealed box at about maybe 1.25ft^3. it turned out to be way too big and i could hardly get any good sound out of my expensive woofer that's supposed to be THE sound quality woofer of the day, it sounded like doody and it would even bottom out on low notes which is almost unheard of for any size W7. so, i decided to build another box and this time i decided to port it. i kept the overall size the same and added a slot port into my design and once again there was a huge difference in quality and output. people would think i had at least a 12 in my truck and i was getting that level of sound out of an 8 in its proper enclosure.

Thank you everyone.  I am now going to send the link for this thread to my friend.  Hopefully He will listen to the advice.  DRAGOON.  please listen to what everyone is saying. If your cousin is such a good installer, and he will install anything for a 6 pack; why are you talking to me?

well if you got an 8" sub that recomends .5 cubes and your box is 10 cubes your sub will sound realy bad.

KyleRozema