Control Room Design help / abandoned temple

Hi everyone, This forum looks great and i feel lucky to have found it. I live in massachusetts and my buddy and I are finally renting a space specifically for recording. It's beautiful and massive (57'x43'x30ish) and sounds great. Our goal is to build an unobtrusive, comfortable and ideally flat (of course) control room given the following situation: -$2000-3000 -we have scavenged lots of supplies from demo sites and personal stashes, (glass, doors, rigid fiberglass, auralex sonoflat panels etc.). -Not messing up the walls (they are old and historical) -We don't use soffit mounted monitors (we have ADAM P11a's, NS20's and a tannoy sub). We are currently designing and hope to start building by the end of the week. I am posting here because I am hoping to not be kicking myself too much afterwards. We originally wanted to build a pentagon shaped control room in the top right corner, but aesthetically it made sense to place it as shown below. Plus the "machine room" shown is an empty 12' by about 5' room recently built and is the only wall we can really mess with. I designed the room to be 11.5'H x 14.72'W x 17.71'L based on the 1:1.28:1.54 ratio i had read about. That is shown below in black. I also thought about pitching the walls out (shown in purple). FIGURE 1 1. Is this a good design? 2. Should we angle the walls (shown in purple)? If so, how much? 3. Would you guys recommend something different? ---------------------------------------------------- After reading the warehouse post, i drew something based on Kendale's 1st post in that thread: FIGURE 2 4. is this better? or too complex for people in our financial situation? (we do have a contractor friend who is overseeing) 5. how do we know what angles to build, what lengths, etc. . for a room this shape? 6. Is this sort of design relevant to people who DONT use soffit mounted monitors?

Aloha and welcome to the forum, Chris Congrats on your studio build!

I designed the room to be 11.5'H x 14.72'W x 17.71'L based on the 1:1.28:1.54 ratio i had read about.

In Rod Gervais’ book “Build it Like the Pros,” he points out both L.W.Sepmeyer’s & M.M. Louden’s formulas most widely used in professional studios worldwide. He also notes that the orders listed are (top to bottom) the first to third best ratios in both cases. Just curious, why did you decide on the "second best" set of ratios?

2. Should we angle the walls (shown in purple)? If so, how much?

Here's an excerpt from the SAE website -

the first thing you must do is eradicate all the parallel walls in a studio design. I believe that a wall must be at least 12 degrees off parallel to stop parallel wall standing wave interference. That's either one wall at 12 degrees or two walls at 6 degrees each. If you can afford to make the angle bigger, do so. Also you can create angled walls within a rectangular room by adding acoustic treatment. (Note: having non parallel walls doesn't entirely stop standing waves - they still form within a room but along different lines of repetition). The main reason for having angled walls in a control room is because of reflection control of the high frequencies for true imaging from your speakers. This effect also happens between the floor and the ceiling so to stop the effect you must angle one! well it's not going to be the floor is it. I must state here that putting angles into the ceiling is expensive so I would recommend that for the home studio you use the acoustic treatment to break up the ceiling. - John Sayers

3. Would you guys recommend something different?

For starters, if you could provide more info on your requirements/environment/type of music/how loud/iso requirements/etc - basically, if you can answer the bold points here: http://www.johnlsayers.com/phpBB2/viewtopic.php?t=3231 it would assist us greatly in making some applicable suggestions. Next, perhaps you might try using the "first choice" ratios from either L.W.Sepmeyer’s & M.M. Louden’s formulas, you would eliminate that variable. Based on your 11.5' height (so is that 11' 6"?) and M.M. Loudens ratios (gives you a bigger control room and it looks like you have the space to do it in) 1.00 1.40 1.90 = 11’6” x 16’1” x 21’8”

5. how do we know what angles to build, what lengths, etc. . for a room this shape?

Here are a few bits of information that I've collected along the way - • It is better to start with a longer front to back dimension than the side to side dimension because you don't want rear reflections to interfere • Soffits angled 30 deg. in from a flat wall result in speaker baffles being perpendicular to the two legs of equilateral triangle comprised of two speaker centers and a point about 10" behind your head • The baffle extension (the face of the soffit) should be as large as you can make it, up to about 45" in each direction from the woofer in a system with a LF cutoff of around 45 Hz - There's a formula based on LF cutoff that ensures full 2 pi response for the woofer if the baffle is at least the size obtained in the formula's solution - • Distance to wall behind speakers will change response drastically - there is a wall bounce calculator on the Acoustics forum that's fun to play with (needs Excel) • Moving either speakers or your head by as little as an inch or two can sometimes make drastic changes in response, due to modal peaks and dips. • Left/right room symmetry (at least within a foot or two of ear height) is important for good stereo imaging. • Roughly 38% of total room length from the front wall • Equilateral triangle formed by left, right mix position • Monitors should NOT sit on the console but behind, placed on heavy decoupled stands - console placement causes early reflection problems in most cases, unless the console is slanted down in front a LOT. • Monitor angles 60 degrees • Monitor height – woofer at ear level (avoid mid point of floor to ceiling measurement – either sit higher or lower if necessary) If you want to mount them high you must angle them down so that they point at the engineer. • Angled side absorption panels – left/right of mix position • Side walls 6-12 degrees • Ceiling 12 degree slope or acoustic treatments Perhaps something like this? (attached) Hope this helps, Aloha 8)