I spent this weekend making a start on the internal wall and door frame. This creates the structure to support the sound door separate to the external door. You'll need to refer to the drawings but you'll see that it creates two alcoves in the back corners which will be filled with mineral wool.
I firstly cut the sole plate to length, marked up the position of the stud-work uprights for the wall and drilled two holes for the through anchor bolts. I then routed out four grooves on the underside to feed the various cables under the floor. This was then placed in situ and drilled through into the concrete floor ensuring at least 2" of depth into the concrete. The through anchors were driven in and nuts tightened up. I'll be adding a couple more of these later but these two keep the sole plate in position very well.
I had to do a bit of thinking as to how the ceiling drywall would be secured at the point of the wall as I couldn't get to the area where the screws would need to go. In the end I attached the top plate to the joist at this point and the rest of the wall will be constructed between the sole and top plate. This created a ledge one side where the drywall would sit and screwed the other side to retain it. I will then screw through the top plate into the plasterboard to further secure it in place. I had to cut the inside edge of the top plate to the 7 degree angle to make it square with the sole plate and the stud-work uprights, this was achieved easily using the circular saw set at the required angle. I made sure that the top plate was perpendicular to the sole plate using a long, reasonably straight piece of timber, between the two and offering up the spirit level while the top plate was clamped to the joist. With a few taps with the hammer working along I achieved a good upright relationship between the two. The top plate was then drilled and screwed to the joist.
I then cut two side stud-work uprights and fixed them into place and two additional uprights which will form the two external corners where the alcoves start. These areas will eventually be filled with mineral wool floor to ceiling to form the rear corner absorbers. I need to finalise the size and layout of the doorway frame before completing this wall but it will almost certainly require at least two more studwork uprights.
Since last weekend and further to some discussions on cubase.net I have decided that I will most likely have the DAW (Digital Audio Workstation), or PC if you like, located in the space between the external wall and the internal wall. This will provide excellent isolation of computer fans and free up some valuable space inside the room itself. You'll see as the build progresses that space is going to be at a premium in this room and the more space I can save the better. It isn't a done deal yet as the space in this doorway area is very limited and the computer box is quite big. There are other considerations here as I'll need to run the break-out box for my sound card (Edirol DA 2496) from the DAW to the desk and I'll need to make sure it will be OK with the additional length cable. I'll also need to run two monitor leads and mouse & keyboard cables. Though looking at it the length is not likely to need to be any more than 5 metres - so it should be OK. I have allowed for this in the cable routing under the internal wall so all being well that's where it will live.