Very Quick Questions on building Non-Parallel Walls

When building "false" walls in front of existing walls to get rid of parallels (not for isolation), is all I need framing and a single layer of drywall? Do I need to fill the space between the true wall and the false with any insulation? I am wondering if the single layer of drywall in the false wall will reflect all frequencies enough to negate the parallels between the the existing true wall and the opposing wall... Thanks

I hope others pipe in, but my gut feeling is that although the mass of one layer of drywall is probably pretty good for reflecting high frequencies, a lot of low and low mids my pass through. More mass will reflect the lower frequencies, but then you have to deal with them inside the room by absorption. Perhaps adding some absorption between the walls wil help. I know... That does not help much. Make sure you actually put enough angle on your wall to actually help, otherwise trapping the parallel walls with broadband absorbers would be better and save you some room.