A simple Step by Step to Calibrating a 5.1 Studio

For my major project I have chosen to do a complete sound replacement of a scene taken from the 2016 horror flick ‘The Conjuring’ the scene involves foley, composition and a lot atmosphere effects like rain, wind, thunder and lighting. Because of this I and my partner John Blinco thought it would be great to try our hand in 5.1. This is the first time I have ever done anything in 5.1 and is completely new to me and John. Both of us are quite experienced in mixing for normal 2.0 environments from our long history of recording bands and other visual media projects, So we understand the basics of mixing and panning things within the stereo field. During this Trimester we got shown a few basic things when it comes to 5.1 mixing which helped us understand the workflow a lot easier, but the one thing we never thought about and is an industry standard when coming to working in any studio whether it’s 2.0 or 5.1 is calibrating your speakers. When you think about it makes perfect scents. There has been plenty of times I have walked into the studio and things have been misplaced or one speaker is louder than the other and when mixing this can be a simple mistake that will make your mixes suffer.

Why should you calibrate your studio monitors?

There a few reasons why you would want to calibrate your studio, the first reason would be to make sure you are monitoring at the correct sound level based on the size of your room. Most studio control rooms are relevantly small, with smaller monitors so you would want your unity monitoring level to be around 78 – 80dB. If you have a bigger studio you want your unity monitoring level to be around 80 – 85dB. The second reason is you give yourself more headroom to play with when mixing. Because you have controlled the overall sound level of your studio this gives you the freedom to push your dynamic during the mix stage. The last reason is imaging between the speakers, even know you might have the volumes on each speaker set to the same level, each speaker will be different by a few dB. This could be due to the location of the speakers, the material that surrounds the speaker and it even comes down to when the speaker was made, nothing is made identical so even that would make a slight difference. That’s why you calibrate the monitors so that everything is at equal level and balanced. Now you know a few reasons why you would calibrate a room lets look into what you need.

Tools needed to calibrate.

Before you began you need to get your hands on the right tools, there is much but having theses tools will come in handy each time you set up a studio.

SPL Meter

This is your number one tool when calibrating your studio, SPL Meter reads the sound pressure level (dB) produced from your speaker. This will help you read the level of each monitor and adjust it until you get everything producing the same dB level. If you can’t afford or get your hands on a portable SPL Meter like a Tenma meter, then you can download an SPL app on any digital advice like a laptop, phone or an Ipad.

Camera/mic/music stand

This will help you set up your SPL Meter, most SPL Meters can screw on to a simple camera stand or you can by an SPL holder which can be screwed onto a mic stand. If you don’t have a stand or an SPL Meter you could just a guitar or music stand instead, as long as you can place your SPL Meter somewhere stable allowing you to work hands-free.

XLR mic cable/Tape measure

This will come in handy when adjusting your speakers while changing your studio imaging. You can use anything really you just need something that you have to use as a measuring device.

Hearing protection

This one is important, as engineers you don’t want to risk damaging your ear/hearing at all. Because you will be pretty close to the speakers while adjusting and changing the volume of them you want to make sure your wear ear protection.

Calibration (Step-by-Step Process)

I’m going to be calibrating the room for 5.1 (surround sound). The method is the same for 2.0 but involves more speakers, with 5.1 you have an L (left) C (center) R (right) Ls (left side) Rs (right side) LFE (Low-Frequency Effects or Sub). The aim is to get each speaker peak at 78dB and the LFE speaker at 85dB when the volume is set to unity.

Step #1 (The sweet spot)

Set up your stand and SPL meter in the center of the room or as some engineers call it the ‘The sweet Spot’ or ‘X’. This is where you will most likely listen to your mixes. In the case of 5.1, this would be the center of the surrounding speakers. Once you find the sweet spot set your stand to the same height as the speakers (head height when sitting down) then face it upwards to get an even reading within the speaker field.

Step #2 (Imaging)

Using your tape measure or XLR cable measure the distance between the SPL meter and the speakers. Do this to the center speaker first then repeat the same process for each speaker in the room making sure that all the speakers measure the same equal distance. Doing this will create balance and unity between each speaker. Which helps with the imaging when mixing or recording.

Step #3 (Setting up your DAW)

Now you have the speakers nice and equally measured you need to turn the volume all the way down on each speaker. Once you have got everything ready to go its time to boot up your interface, computer and chosen DAW. Once everything is set up you need to go into your DAW and select the right interface, then set up your I/O’s and make sure you select the right output for 5.1 or 2.0.

Step #4 (Signal Generator)

Now you have set up your interface and I/O’s. It’s time to set up a new mono track and insert a Signal Generator plugin set it to pink noise at -20dBfs. On your mono track make sure you set the fader to unity (-0dB).

Step #5 (Time to Calibrate)

Now you have everything set up and got the pink noise generating, it’s time to calibrate. The first thing you need to do is set your master volume on the desk or interface to ‘Unity’ and be use to keep the volume the same during each speaker setup. This is also a good time to prepare your PPE. The next step is to open up your panning in ProTools and began to send the signal to your first speaker. Then adjust the volume on the back of the speaker until your SPL meter reads 79dB, this will take a few goes going back and forth and adjusting the speaker’s volume. But once you hit 79dB repeat the same process on each speaker. Once you have your 5 speakers sitting at 79dB, its time to move on to the LFE (Sub) for the LFE you just repeat the same process but this time you are going to set the speaker to 80dB. Once you got everything balanced and sitting at the recommend dB your room will be fully calibrated.

Well there you have it that’s a simple way of calibrating a studio, even know its pretty straight forward it really does make a big difference when mixing.