The best wall construction

Hi! I'm planning to build a new wall in my basement/dedicated listening room. The wall will separate an open space on the left from the left front speaker. Now the basement configured in such a way that it only has three walls: front, back and right.
So here is my question: the proposed wall will be only decorative, but still will need to serve certain acoustical purpose. How and what from should it be constructed? I was thinking about 2x4's covered with drywall from both sides. What kind of insulation do I need to use in between? Can some kind of acoustic panel be built-in in the first reflection point, or I will need to use hang-on acoustic panels?( I was planning to use DIY panels made from Owen Corning 703pressed board). Any input will be greatly appreciated. Regards.
Go to they can give lots of good advice, and/or act as consultants.
I agree with Narchy. Rives is a good place to start. He has a forum on acoustics too:
Rives Acoustics Forum

I helped a friend build one wall to enclose a listening room and he did not want to get too exotic. We just double layered the drywall, put studs on 12 inch centers instead of 16, and didn't spare any screws. It worked out quite well with little extra costs.

But ask at Rives' forum. He is a pro.

I remain,
I would put in another reccomendation for Rives. If I would have known about their service about 2 years ago when I built my own room it would have been worth every penny of their fees to help me realise the best acoutics possible in my space. It is almost impossible for a novice to get things right without any help, or it takes tons of experimenting and work to get things right, or you can get lucky. Rives can work with what you have to work with and can most importantly give you the instruction to build the neccesary treatments that your room will require. This alone is worth their fee. If you are running a top notch (usually pretty expensive) system then it's a no brainer to get some pro help. The room is indeed the most important component in your system
If I was in your position, I would build a 2x4 stud wall with drywall on either side. In addition, on the listening room side, I would put a material called sound board underneath the drywall. It's made by a company called Celotex. A big name in the building industry. Almost sound proof, it does a great job at deading the room.