Placing Instruments in the Stereo Soundfield: A Chart

Keep this Reverb Depth Chart handy whenever you have a complex, multi-instrument arrangement and need to place your instruments in the stereo soundfield with care.

By Jon Chappell

This chart shows instrument placement in the soundfield according to stereo width, distance, frequency response, and depth. (Click to enlarge.)

Many people apply reverb to their tracks simply by using their ear. They find a program that roughly describes the environment they’re looking for (large room, small hall, etc.), and then proceed to tweak the controls to taste. This is fine for a solo instrument or small ensemble. You can usually get pretty good results by loading an appropriate reverb preset on an effects bus and have all instruments share that same reverb. This works whether the reverb is a hardware unit you’ve patched into your mixer or a plug-in you’ve launched and assigned to an aux track created just for that purpose.

But when you start to get beyond a basic rock band, you find you really need to address reverb as a whole separate issue and create a reverb strategy or even a written plot that can be considered and analyzed for its own sake. For example, in an orchestra setting, you should know at any instant—without looking at the board for cues!—whether your French horns or your strings are further back in the mix, with respect to their reverb treatment.

DISTANCE RUNNING

Of course, reverb is only one way to bring instruments close up or push them further away in terms of placement in the soundfield. There’s volume (quieter sounds are perceived to be further away), mic placement (distant miking creates a greater sense of space), and frequency response (sounds that emanate in the distance will have reduced high frequency content). Reverb programs are very good at supplying these qualities for you, along with their reflected-sound emulation, but it’s always good to know how the aspects of a sound are affected when they’re actual physical placement in the space changes.

Some years ago, I received a helpful chart from Alesis that accompanied one of their reverb units (I think it was a MicroVerb). I immediately digitized it, modular-ized it, and repurposed it for my own uses. The chart uses 3D shapes, vertical stacking, and shading to illustrate a soundfield plot for a variety of instruments and instrument families. For large ensembles, I often start with this scheme before making alterations according to my specific scenario. More often than not, I stick with the original plan. If I change anything, at least I’m aware of deviating from my original, and I have a good reason for doing it.

CHARTING YOUR REVERB SUCCESS

The chart is self-explanatory (you must use the Key on the right to understand the shapes, placement, and coloring of all the symbols), and I like the intuitive use of width and height to convey the 3D nature of the soundfield. In my own digital copy, the instrument modules are removable and sizeable. So if the situation warrants it, I can delete the background vocals and horn section modules, leaving just the instruments in my particular arrangement. I can stretch the modules to increase their width and move them along the horizontal axis to change their pan position. I leave the height alone, because the frequency content doesn’t change depending on your soundfield-placement experiments. I like to leave the depth (indicated graphically by the perspective drawing of diagonal lines) of the modules where they are too. For example, I almost always leave the kick and bass guitar dry and the strings as the wettest element in the mix.

CONCLUSION

This chart won’t solve all your space and placement issues, but I found I couldn’t disagree with a single aspect of it, as far as the “classic” way to treat instruments in a mix. That’s not to say you won’t find equally viable solutions—or better ones for your own purposes—but more often than not, if I start here, I don’t have to stray far to find the right placement for any ensemble. And working with the chart and noting the deviations I make gives me insight into instrument placement gives me a perspective on my mixes I might not have otherwise.