Room Setup 101

There is an acoustics expert out there who says his products affect sound waves at a some kind of a voodoo molecular quantum level (and needless to say they are very expensive) and hey - maybe they work. Nobody knows, but they look pretty. On the opposite end of the spectrum we have the veteran studio owner who told me "These fancy designers come down from 'that there London' and want to charge you a fortune, well...we just played around with things until it sounded good" - and his rooms made a lot of hits, including Bohemian Rhapsody! I can imagine all kinds of things living in the ceiling as absorbers as he is a very practical man and always at war with the squirrels who knock out the power. It's confusing as on one hand it IS science and on the other....it's whatever works. I was always very interested in this.

I have good news and bad news. Yes, there are many professionally designed rooms in the world, and most of those really do sound good. There are many MORE rooms that don't that some call studios, which I call "rooms with some gear in them". People spend inordinate amounts of cash buying esoteric gear and expensive monitors, asking why their own mixes don't work and often, it comes down to one big factor apart from ability - the room. At the lower end of the market where I started that is usually confined by the amount of room available.

Most small rooms are not designed for listening to audio, end of story. The limitations of space alone make it very hard to treat low end, and a lot of these rooms aren't set up with listening as the prime purpose, more usuals based on where things fit, or where the gear looks right. Is your room as symmetrical as possible at the listening position? Me...I'd put the considerations of setting up the room to sound good first every time if possible over anything else, and go for overkill. Everything in your room will have an effect, from flooring to wall treatment, but first - we need to figure out where things go.

You've seen pictures of acoustic foam tiles. Many of these are junk. You are almost always better off going to your local builders merchants and buying some semi rigid rock wool slabs (RW-45 or similar) and making some panels yourself. If you don't believe me, look at the absorption specs. It's not hard and you haven't really paid your dues if that nasty fibreglass hasn't given you a nasty rash at some point in your life. Seriously though be careful and use appropriate protection - it's dangerous and unpleasant stuff, but very, very effective. Making a wooden frame the size of a rock wool slab and covering it in fabric will cost way less than buying anything half decent and work better, I assure you. If you're loaded then good for you - I personally think there are some very strong melamine foam based solutions out there, but this is a different kind of foam - we're talking 10cm+ thick slabs of the stuff in huge sheets, not some little tiles. It's safe for fire risk (also a consideration not to be taken lightly) and genuinely effective instead of just looking right.

Another time I hired a guy to come and help fine tune the bass traps I bought for the room I was working in as I am conscientious like that. He came for a couple of hours with his laptop and reference mic, drank a lot of tea, stroked his merlin beard a few times and charged me a couple of hundred quid. I felt like something happened, but of course the other guy that worked in the room immediately said it "sucked all the life out of the room"...so who knows. On paper, measured it WAS flatter in the low end and sounded better to me (we had monster ATC's ...but nobody's ears are the same).

If you measure your room, you will immediately discover the horror that your room is nowhere near where it should be, and even if you treat fairly heavily that it won't be ideal. In the real world, though...look at a lot of rooms, racks of nice hard reflective gear in the way, big panes of glass, huge mixing desks putting a big hard splashy surface right below the monitors, and yet they work. In making the transition to working in fully pro studios I think I wanted there to be some big secret, some magic, but what I realised is that "real studios" just made it easier to do what needs to be done, the effort required remains the same, but there are less factors likely to lead you astray.

So how to begin?

Avoid setting up in a corner, and try to set your room up as symmetrically as possible. This means looking at your room, and seeing which wall is going to work best, with the same on each side of the monitors.

If there is a wall on one side, and an open space on the other for example what do you think will happen? The distance between the walls and each speaker has a direct effect on the low end - so ideally you want each monitor to be the same distance from the rear wall and the same distance from the side walls as each other in a smaller room. Let's say your right monitor is closer to the corner than the left because of your room setup. Anything you pan right will probably sound bassier and fatter than it does when you pan it left. Make sense? If you are stuck in this situation, by all means pan it the other way and check!

Same goes with the early reflections (roughly - the reflections from the closest surface to the speaker which will be the strongest next to the direct sound) - same distance, same reflections - equality is good when it comes to treatment which I will cover later.

You often see internizzle peeps shouting about the 38% rule. What is the 38% rule?

In a rectangular room, the best theoretical spot for your listening position is 38% from the wall, as due to our buddy physics and the magic of the golden ratio the average response will most likely be less problematic with peaks and nulls.

With regard to this I just want to cover four points:

1.) That means 38% from either the front OR rear wall, not just the front.

2.) Wes Lachot, the acoustic designer and originator of the 38% rule states: "it's a guideline, not a rule"

3.) Nobody EVER mentions your ceiling height when they talk about this. A room is three dimensional, so floor to ceiling ratio also has a profound impact.

4.) In a bigger studio the mains are often soffit mounted, the studio is designed around that, they are hardly ever used and the nearfield position is on the meter bridge…just because it’s there.

But hey, we have to start somewhere, right? So sure, start by placing your listening position 38% of the way into the room. Why not. You’d just put it where you think it looks cool otherwise, wouldn't ya?

Room geometry setup

"I have a long wall, and a short wall. Which way should I set up my room?"

Aim down the longer wall - it will take longer for the sound waves to hit the back and reflect back which usually results in the likelihood of being less nulls in the bass spectrum at the listening position. So set up your listening position, then place your desk and monitors in front of that.

"That's ok, I have a cool looking diffuser back there."

Nah mate. You will sadly disappointed if you look at the effective frequency range of your QRD diffuser and what it will actually diffuse! You're probably not building three foot deep diffusers which you'd need to do to have any effect at 100hz are you? Something 6 inches deep is only going to kick in around 650hz, and go up to about 7k with very narrow wells. The same applies to skyline type diffusers which tend to start even higher.

"That's ok I have a bookshelf back there. That totally works!"

Lol.

Any uneven surface provides diffusion, this is true, but how effective it is and why the quadratic diffusers have any merit comes down to the physics applied. Less application of the science, the less effective. How deep are the different "wells" provided by the books, and how wide are books in general? Not very.

What about speaker height? I see you kids doing some crazy things, speakers on desks two feet below your ears, or making stacks of speakers or speakers on the wall. Get your tweeters at, or near to ear height. If they are above or below what happens? Less high end, which means you'll add too much. Although...maybe you have a monitor which is super bright and moving it a little may actually help.

Speaker angle? An equilateral triangle between you and the tweeter and the centre of the tweeters relative to each other is a good starting point, angled slightly towards you, inwards around 30 degrees or so. How precise you make this triangle will affect the size of the sweet spot, so again practicality over-rides.

How far from the wall?

Here we are going to deviate a little bit from common sense. Since we used the 38% rule to determine our listening position, that is dependent somewhat on that. But here we go: where things sound best might not be the best location from a scientific point of view. In reality this means: putting your near fields closer to the back wall than you might imagine - what you want to go for is even-ness and a low end that feels right as you will instinctively aim for that. There will be a bass lift as you get close to the wall, but when a monitor is between 1 and 2.5 metres from the rear wall some hard to treat weirdness can occur in your low end. Listen to a load of music and you'll soon find a place that seems right. You may also have some EQ settings on your monitors, and now is the time to tinker with those - AFTER everything sounding pretty decent. Ok. we are now ready to begin!

Next week, acoustic treatment and bass traps. Kill me now. Before I die, visit me on baldenglish.com and let’s make some records.