L shaped control room design

Hi folks, after reading some other threads I thought I'd best do this before I started constructing anything! The proverbial downstairs basement studio, L shaped though, goal is acoustic treatment to get a consistant listening environment. Its just me, my guitars, amps, a computer, a few bits of rack gear, no need to account for excess noise or bands (except maybe there is an opportunity to stop leakage going upstairs through the ceiling?). I don't think noise spilling to/from the outside is a problem as I border on a park on one side (out the window) and under the house on the others. Its an L shape room instead of a rectangle. I'm not sure how to deal with that either in terms of placement or treatment.....at the moment I have the monitors at the thinner end, with the sliding door to my left and the window to my right. I swept through some sine waves with the NTI Minirator and that was pretty scary and inspired this post. Clearly some problems with LF nulls, and I guess the window causing problems at higher freqs. I would like to move around a little without things disappearing altogether! Mostly though I don't want to be guessing whether particular frequency ranges actually exist or not. Other threads indicate start with broadband LF absorbers? Not sure what to do about the window? I can leave the sliding door open if that helps with anything? My monitors are Yorkville YSM1p's, so I have the option of applying bass roll-off depending on where they are placed. The walls are a plasterboard stuff with ordinary fiberglass bats for insulation. FLoor is carpeted concrete, not sure what the ceiling is. My budget would be say up to $NZ 1000 (say $US 700) if I spread it over a little time, ie build a bass trap one month, do something to the ceiling another. thanks in advance, Mike

So what park are you next to - I grew up in Auckland :) what if you tried something like this? cheers john

Hi John - how about that! I'm in Glen Eden, near Ceramco Park. I hadn't considered a design like that, which I guess is why it was a good thing to ask :D Much appreciated.

I lived on One Tree Hill :) cheers john

ok, so lets say I don't particularly need the little booth to the right of the listening position. Would that still be the layout you'd recommend?

ok, so lets say I go with this design. Can I have a bit of guidance on what types of walls are where? Starting at the back, I assume thats a bass trap? Are the actual dimensions (depth, angle) important, and what is recommended to go in it? Is it just 4", rigid fiberglass at the front like http://www.johnlsayers.com/HR/index1.htm? or multiple layers? or many hanging absorbers like the LF ones on http://www.saecollege.de/reference_material/? At the side rear, the brown line up to the sliding door - is that anything in paricular? A side wall absorber? Moving forward, just to the right of the mixing chair, is that slotted corner absorber of the http://www.johnlsayers.com/HR/index1.htm variety? or simply a rigid fiberglass absorber from floor to ceiling as in http://www.ethanwiner.com/acoustics.htm ... ss%20traps? Now, the 2 new walls (in black). What type of constructions is recommended here? bearing in mind I'm not too worried about TL, just creating a good listening environment. Finally the monitor area. I'm not sure I want to go down the soffit mounting road....seems like a lot more work. If I don't, would this be two broadband corner absorbers and a LF absorber in between? Or a single structure of some kind? Will I have problems if my ysm1p's are backed up to the corner absorbers? Is there a distance I would have to keep them out? Or do I need to bite the bullet and go soffit? many thanks for any input :D