here a bit further north, i'm doing 2 in of foam insulation, 2x4 in front of that... fill with pink fluffy.What part of the world are you in? I am in the midwest, so I am putting up 1" of foam insulation, with 1" air gap, then 2x4 stud will. That's just general wall construction in our area for a basement. If you want to do soundproofing you could decouple the walls with IB-3 clips or clips and hat channel. Then 2 layers of Type x 5/8" drywall with Green Glue between the layers. If do this with the IB-3 clips you are looking at around 6.75" to 7" from the foundation wall lost. If you do the clips and channel you will about about 1 1/4" or so.
Check out Soundproofingcompany.com for more information.
it's possible to do the ceiling and walls such that the ceiling is contiguous and sealed, but the walls don't need double drywall because that seal is kept on the ceiling... you essentially do the ceiling first, then drywall with double/gg... then the top plate of the wall is attached to the ceiling with IB3...