Unusual shaped room - need advice please!

[tun]

Hi guys,

I've been reading so many threads regarding room treatment my head is spinning... I've ordered the Carl Hopkins Sound Insulation book and read as much of the BBC literature as I can, but I'm still unsure how best to tackle my new room.

As you can see from the photos it's almost an 'L' shape with awkward corners. Also there's fitted wall units and an a.c. unit that can't be moved... and the window goes straight into the corner. I can't move the curtains either. The problems seem endless even though it's a nice size room.

I'm planning 2 x large floor to ceiling superchunks to go in the corners behind the monitors. However, the one behind the left speaker can only go as high as the cupboard on the wall, and then I'll make a shallow one to sit on top of the cupboard in the tri-corner. Also, the superchunk behind the right speaker won't be able to go tight into the corner because of the curtains.

I'm planning corner traps for behind the listening position (either side of the bed) but I'm not sure about width, depth, height or placement; whether or not to nest them etc. Then I'll be looking at a ceiling cloud and absorbers/traps on either side of (and behind) the monitoring position. Hopefully the bed will be removed.

I'm going to put the monitors on stands asap and the old grey desks will be replaced with a minimal desktop area workstation to reduce reflections... hopefully create a RFZ at the monitoring position. I've even considered rotating the workstation 180 degrees so there's nothing between me and the monitors, but I guess there must be a valid reason for not doing that or everyone would be doing it, maybe the shape of the ear has something to do with it?

Anyway, at the moment the room is really echoey, I've been walking around it making lots of strange percussive vocal noises and there's a very 'metallic' natural reverberation (good job there's no neighbours). Tomorrow I'm going to buy a Behringer ECM8000 and try to start getting my head around REW!

My aim is to get the room as flat as possible down to as low as possible; 40-50Hz would be nice, with reverb times down to those found in typical commercial control rooms.

I realise this has been done to death but I couldn't find anything directly related to strange corners, and I'm confused about so many things such as carpet etc... different people offer differing advice on so many things! I openly admit I know almost nothing about acoustics.

I'm a musician/producer and just want the room finished asap... as such I'd happily pay for a consultation.

I'd be extremely grateful if you could look at the photos and give me some advice.

Pretty soon I'm going to be doing a very significant gear upgrade: RME Madi card, top end AD/DA, Valley Hills Equinox and ATC SCM50 ASL Pro's. It goes without saying I need the room as good as possible - there's no point spending around £8k on monitors if the room isn't up to scratch.

Many thanks in advance.


plan view


front right corner


back right corner


front left corner


back left corner


toward right wall


toward left wall


left wall and back left corner with door


window and front left corner

[Jens Eklund]

A good start:

Acoustics/Treatment Reference Guide - LOOK HERE!

[tun]

Thanks Jens!

[tun]

After a lot more reading...

Next on the list is 1st reflection points but first I've decided to get plans together for corner superchunk traps. I've nearly finished the design and gotta say thanks to bwo for the inspiration and photos of his build!

First, I've done plans for superchunks for the corners behind the listening position. I want them to be modular and sturdy so they're stackable; 2 will just about fill the floor to ceiling space. They're designed to take rockwool batts cut into 450 x 450 x 600mm triangles, and I've found a 32Kg/m3 6" thick un-faced fibreglass batt that I think'll be suitable.

I'm also planning to use the same 32Kg/m3 batt for bigger superchunks: 600 x 600 x 848.5mm. These will go in front of the listening position (I intend to post a plan and 3D render of these too... asap).

If you look at the plan view you'll see I've decided to use 1"x2" verticals (25.4mm x 50.8mm) for all the superchunks cabinets. Also, the room has a skirting board that protrudes about 19mm out from the wall. So, if I sit the corner traps directly on the floor there'll be a gap of around 44mm between the rockwool and the wall surface. Is this acceptable? Will this air gap seriously compromise their effectiveness?

If so, would it be better to sit the frames on something to raise the bottom of the traps off the floor to clear the height of the skirting board? ie: around 100mm off the floor, thus reducing the space between the wall and the rockwool to around 25.4mm? Or would this be worse as there'd be a 100mm deep section of floor/wall tri-corner exposed?

If I raise the superchunks to clear the skirting board with a view to getting the rockwool nearer the wall surface what should I do with the exposed floor tri-corner? Is it going to make much difference?

I guess what I'm trying to ask is which is the lesser of 2 evils?

Also, to avoid absorbing too many mid and high frequencies would my superchunks design benefit from a thin membrane layer such as cling-film or paper applied to the hypotenuse face of the rockwool triangle? Or would 3mm hardboard be even better, as used in the BBC A10 and A11 modular designs? Or have I got it completely wrong in that membranes should only be used on thinner absorbers, ie: not corner superchunks?

I'd really appreciate if you could clarify these points for me. I really want these superchunks to do what they're supposed to do; trap the bass! I really don't want them to end up as broadband absorbers if I can help it!

Many thanks.