Choosing a Room for a Control Room

[shragledagle]

Hi,

I'm trying to determine which of two rooms to use for stereo mixing and mastering, so basically a control room. I don't intend to do any live recording. Any help in deciding which room better suits that purpose would be much appreciated. I would also like to know where to place my monitors and where to sit, once we determine which room to use.

Both rooms are located in the basement of a detached private dwelling, I have no concerns about noise or soundproofing. The exterior walls of both rooms are concrete foundation walls from the floor to the ceiling. All of the walls and ceiling, including the beam mentioned below, are covered in drywall (gypsum). The floor is laminate over concrete in both rooms. There is also a bathroom and a workroom/storage area in the basement.

I intend to use Adam A7x monitors with an Adam Sub8, I also already have some 9" 705 bass traps and will be building more to fit whichever room is chosen. The budget is not a concern at this point.

The larger of the two rooms, the dimensions of which are shown on the attached plan and is designated "Proposed Studio". The ceiling height is 7' 4". There is a steel beam running across the ceiling. The beam is covered in drywall and extends from one end of the room to the other, and a small part of the ceiling has been lowered, all as you can see in the attached photo. There are two windows along wall "A". There is a 4 inch ledge from the floor to about 1/2 way up the wall, running the length of walls "A" & "B". A portion of wall "B" has been built out to conceal an old brick chimney, no longer in use. There is an open ceiling directly above the staircase that leads upstairs. I've tried to show all of these details in the attached plan/screenshot.

The smaller room or "Alternate Studio" is rectangular and measures 10' 2" x 12' with a ceiling height of 7' 4". There are no windows, just a door as seen in the attached plan.

I've also included a rough SketchUp file showing the entire basement.
The white room is the "Proposed Studio"
The blue room is the bathroom
The pink room is the "Alternate Studio"
The green room is the "Workroom/Storage"

Which of the two rooms would make a better control room? Are the beam, lowered ceiling and/or irregular shape of the "Proposed Studio" problematic? I'm also concerned with the small size of the "Alternate Studio". Is the room too small to use for a control room focused on mixing bass heavy music?

If my best choice is the "Proposed Studio", which wall should I be facing when I'm sitting at my desk? Should I be facing wall "A", "B" or the wall opposite "B"? If I'm facing the wall opposite "B" will there be enough room to place absorbers at first reflection points?

If you have any questions or need more info please don't hesitate to ask.

Thanks in advance for all replies.

ShragleDagle

[JasonFoi]

Heh, same advise i gave on gearslutz.

[Soundman2020]

Hi there "ShragleDagle". Welcome!

General "rules of thumb" for choosing a room for a home studio:

- Ceiling as high as possible
- Room as large as possible: ideally 200 square feet or larger floor area, and greater than 1600 cubic feet volume.
- Symmetry: draw an imaginary line down the center of the room: the left half should be the mirror image of the right half.
- No doors or windows in corners.
- "Room ratio": Check that the relationship between the dimensions of the room (L-W-H) is not close to any of the "bad" ones, and is reasonably close to one of the "good" ones. Use a room mode calculator to simplify this task.

Frequently it isn't possible to meet all of those, so you have to compromise: Symmetry comes first (if the room is not symmetrical, then the sound stage and stereo image will be skewed, and so will your mixes). The comes Room Volume: bigger always beats smaller. Then the others.


General "rules of thumb" for layout within the control room of a home studio:

- Face one of the short walls, with the speakers aiming down the longest axis of the room
- Place the speakers hard up against the front wall, very roughly 30% of the width away from the side walls.
- Leave a gap of 10cm/4" between the rear corner of each speaker and the front wall.
- Set up your chair such that your ears will be about 38% of the room depth (distance from front wall to back wall) away from the front wall.
- Aim both speakers at a spot about 30 cm - 60cm (12" to 24") BEHIND the mix position, depending on room size and other factors.
- Do a "baseline" test like that in the empty room, using REW ( http://www.johnlsayers.com/phpBB2/viewt ... =3&t=21122 )
- Install basic treatment in the room.
- Do a listening test like that, and a second REW test.
- Try "nudging" things around by small increments, one thing at a time, to see if there is a better spot (flatter acoustic response). Eg. move the mix position forward and backwards by small increments (a couple of inches with each step), move the speakers closer together / further apart (one inch per step), move the aim point forwards and backwards (a couple of inches per step).
- Add the sub: place it on the floor, close to the front wall, offset by a foot or two to one side o the room center line. Do multiple tests while moving the sub around in small increments, to find the best location for the sub (flattest room response).
- Once the best spot has been found for everything, do another REW test.
- Based on that test, determine what additional treatment will be needed.
- After building/installing each new treatment devices, do another REW test to confirm that it is working, and see what other acooustic issues still need fixing.

Having said all of the above, your room is a real challenge (assuming you go with the one you show in your single image): If that were my room, I would frame out the front wall and put heavy sheathing across it, to get a symmetrical, flat, smooth, solid, hard, massive surface, and also build a wall with a door in it, across the alcove where the stairs are. The room is plenty large enough for that. Then proceed as above.

Heh, same advise i gave on gearslutz.

I'm not sure what advice Jason gave you on GearSlutz, but knowing Jason, I'm pretty sure it was something similar to what I'm suggesting above!


- Stuart -

[shragledagle]

Hi guys,

Thanks for your replies.

This is the advice Jason Foi wrote on gearslutz:

"Go with the proposed room and put speakers at wall B. I would build out the entire rear wall with fluffy fiber the full 2'4" thick wall to wall floor to ceiling. I would put 2' of fluffy fiber along A&C also to cover C completely and A to match C. I would cover B completely too and place the speakers right up to the treatment. I would fill in all of the ceiling even with the beam with fluffy fiber too. I would not get more 705. With the panels you do have i would take them apart and make some moveable gobos to cover that little hallway opening and put on the opposite wall. Or just build a wall there and put in a door"

So, after considering your suggestions and advice, we want to go ahead with the Proposed Studio. Perhaps creating something similar to the Control Room plan we found on this site. However, we have some questions about how to move forward. Below are two plans we are considering, plan A and plan B.

In plan A, we leave the existing walls (ledge and covered chimney in place), and just build bass traps and absorbers from floor to ceiling. For the ceiling, we also leave the beam and lowered section in place, then level it out with absorbers, so the ceiling becomes a flat surface throughout.

In plan B, we build a new rectangular room within the Proposed Studio, and then build bass traps and absorbers from floor to ceiling. For the ceiling we would lower the ceiling and level it out with drywall so the ceiling becomes a flat surface and then install ceiling absorbers.

Basically we want to know if the symmetrical space created with using just the absorbers and bass traps of plan A will suffice. Or do we need to have symmetry behind the absorbers as seen in plan B?

Thanks,
ShragleDagle

[JasonFoi]

Low frequencies will see the rigid boundaries of the room, and high frequencies will not in both of your scenarios. Its hard to say what effect the uneven surfaces will have modally. If your budget allows I would definitly do plan B. Make sure to demo and fill with insulation any resonant cavities in the current construction, like around the steel beam. Its also important to match wall construction. You dont want a heavy masonry wall on the left side and light drywall wall on the right side. What will you do to address the ceiling beam? Height is valuable in a control room.. Will you be flush mounting your speakers? Whats your plan for HVAC?

[Soundman2020]

Based on your updated design, it seems you are going with speaker soffits in an RFZ style room. That changes everything. In that case, you would not need to build the wall across the front of the room, as the "alcoves" could be used as part of the soffits, and you'd only need to build out a small section to create symmetry. The other wall will still be needed (right hand side), but I'm not sure what the purpose of the triangular "wall" is at the rear of the room.

I'm also wondering why you have yellow "bass traps" in triangular shapes up the sides of the room: what is the purpose of those?

- Stuart -

[Sarahk]

Hi,
Yeah I would rearrange how you set up your room. It needs to be more symmetrical and smooth. Also, I'd recommend having a large room with large ceilings and no doors or windows. With these tips you should have a great area for a control room.

[Soundman2020]

It needs to be more symmetrical

I think we already covered that, in depth, in several places in the thread so far, Sarah.

and smooth

No. There is no need for control room walls to be smooth. In fact, a rough texture can be much better, and small protrusions can be useful as well, provided that they are not located in any of the critical areas.

I'd recommend having a large room with large ceilings and no doors or windows.

And what if these are the ONLY rooms that the original poster has available? Would you recommend that he just give up and not build anything? Or would you recommend, as the experts here have already done, ways to deal with the limitations of this room?

With these tips you should have a great area for a control room.

What are you basing your claims on? Do you have some source that you want to link us to, that would back up what you say?

Also, Sarah, please read the forum rules for posting (click here). You seem to be missing a couple of things!

- Stuart -