Using Pro Tools to Improve Your Listening Environment (Part 1)
By David Franz
Lately I’ve been mixing and mastering tons of projects in Pro Tools for a number of clients. All this critical listening has made me seriously evaluate my studio’s listening environment and the effect it has on the finished tracks. There are many factors that contribute to the listening experience, including speaker setups, acoustical environments, and psychoacoustic factors.
Fortunately, there are several ways you can use your Pro Tools system to improve your listening environment. In this multi-part series I’ll discuss various ways to improve your listening experience — and ultimately, the quality of your Pro Tools projects.
Lost in Translation
One of the biggest problems that people face is getting their songs to “translate” — that is, creating a mixed/mastered track that sounds good when played back on any listening device, from an iPod with tiny earbuds to car speakers to a home stereo. The key is to actually listen to the songs in all of these different environments. Comparing your mix to a reference mix and taking notes on frequency content, volume levels, and other factors is where the real learning takes place.
Unfortunately, you can’t bring all of those listening environments into your Pro Tools studio. But you can hook up several sets of speakers that approximate these environments. Professional studios have been doing this for ages, placing large, expensive speakers next to small speakers (like Yamaha NS-10Ms) and a tiny mono radio speaker (like an Auratone) — and you should too. Seriously think about who is going to listen to your music, and on what kind of systems, then tailor your mixes so they’ll translate well to those playback systems. Here’s a good list to start from:
Being able to easily switch between these four types of devices in your studio will give you a better feel of how your mixes and masters translate to other people’s listening environments. DJs should also consider listening through a PA to really get the feel of their mixes on a loud system.
Route It Out Loud
For devices like the Mbox 2 or M-Audio’s FireWire Solo, with only two analog outputs, you’ll need a control surface, an external switching device, or a mixer with multiple outputs to plug in your various speakers and switch between them. For Pro Tools|HD hardware users, Digi 002 users, M-Audio FireWire 1814 users, and anyone using a device with more than two outputs, you can connect your speakers to the multiple outputs on those devices. Then you can use Pro Tools to create and route your signal to multiple output paths.
Here’s one way to do it: First, to avoid signal routing confusion, let’s name the signal paths. Open up I/O Setups by selecting I/O from the Setups menu. Name the bus paths and output paths, as in figure 1. To easily identify the signal paths within Pro Tools, I’ve included the names of the speakers in the signal path names.
Now, “solo safe” all of the tracks (except the Aux Inputs). Making a track solo safe prevents the track from being muted even if other tracks are soloed. To make a track solo safe, Control-click (Win) or Command-click (Mac) the track’s solo button. To make all tracks solo safe, press Alt + Control (Win) or Option + Command (Mac) and click on a solo button. When a track is solo safe, the solo button is grayed out, as you can see in figure 2.
Don’t Fear the Speaker
Once you’ve got your speakers connected, it’s time to make sure they’re set up correctly. When listening to a pair of speakers, the goal is to hear an optimal stereo image. Also called the “phantom image,” this occurs in the middle of two speakers placed at equal height from the floor. To hear the phantom image, your head should be on the median plane — an imaginary line equidistant from each speaker (see figure 4). Ideally your head and the two speakers should form an equilateral triangle: The distance between you and each speaker is the same, and equal to the distance between the two speakers. In this setup you’ll perceive the sound coming from the area directly between the two speakers. (In my studio, it often seems like the sound from my speakers is actually coming from my computer monitor, which is placed directly between them.)
You should be equidistant from the speakers because you want the sound from each speaker to reach your ears at exactly the same time or you may experience the precedence effect. The precedence effect (or Haas effect) occurs when the listener is off the median plane (by as little as six inches), which shifts the phantom image toward the speaker closest to the listener. As a result, the sound from the closer speaker arrives at the listener’s ear first, which may fool them into thinking it’s louder. If you’re basing a mix on this kind of false imaging, you may have to redo the entire thing!
To create the proper listening setup, I recommend using a tape measure to accurately position your speakers. First, sit down where you’ll normally be listening in your studio. Then use the tape measure to approximate an equal distance from your head or chest to a spot on your left and right sides, where your speakers could be placed. A good distance is three to four feet, which is the same distance the speakers should be apart from each other. In fact, the closer you are to your speakers, the less the room acoustics will color the sound. (This is called near-field monitoring, and is the most common approach for mixing.)
Next, place your speakers at equal height from the floor in these approximate positions. If possible, the speaker height should correspond to your sitting height (or at least be pointed to that height). Angle the speakers at approximately 60 degrees toward the median plane. Finally, sit down again, use the tape measure, and precisely position the speakers to achieve the equilateral triangle setup. Now listen to some music and find out if you hear the phantom image. Try moving back and forth along the median plane and moving your head side-to-side. Can you hear the difference?
If you think you’ve placed your speakers correctly but still don’t hear the phantom image, your speakers may be out of phase. Fortunately, this is an easy fix. If you’re running speakers through an amplifier with positive (+) and negative (-) connections, make sure your speaker wire is attached correctly: that is, negative connector on the amp to negative connector on the speaker, and positive to positive. If this doesn’t fix the problem, your speaker cables could be wired in opposite polarity, so try different ones. Correctly connecting your speakers with properly wired cables should eliminate speaker polarity problems.
Getting your tracks to sound great on any playback system is the goal of every mixing and mastering engineer. You can do this in your Pro Tools studio by setting up an easy way to switch between multiple sets of monitors and applying the basic audio principles presented here. Next time, we’ll dig further into tweaking your monitor setup to create the optimal listening environment in your studio. See you soon. Peace.
Like what you see in this column? Check out my book, Producing in the Home Studio with Pro Tools (2nd Edition). You can buy it online right here through Digidesign’s website, or visit www.protoolsbook.com. Interested in personal instruction on Pro Tools from yours truly? Visit www.berkleemusic.com and learn about several amazing Pro Tools learning experiences available online though Berklee College of Music. Wanna see my studio and hear some samples of my work? Visit www.undergroundsun.com. Feel free to drop me an email at email@example.com