Stereophonic Soundstage Image Training Exercises

Most of us consider ourselves fairly adept at visualizing the virtual sound stage presented by a curated selection of recordings through our refined hifi playback system. But when is the last time you really focused, really practiced, really tested your perception of a wide, deep, tall, and clearly distributed array of musicians and instruments?

Or, when is the last time a non-audiophile friend or family member sat down in your sweet spot, listened for a few minutes, and seemed underwhelmed, asking what is all the fuss about?

This week, ASC President & TubeTrap inventor Art Noxon walks us through a training routine, an exercise, if you will, that improves our ability to perceive – and enjoy – the tantalizing experience called stereophonic imaging. Enjoy!

Stereophonic Soundstage Image Training Exercises

This is a learning exercise to help a person understand and develop their ability to perceive stereophonic imaging and soundstage. Its original purpose was to train recording engineers about the difference between mixing on speakers and mixing on headphones.

It was suggested that this training might be a good way for people who have become acclimated to “in-head” listening through the use of headphones and earbuds to expand their listening experience to include the amazing “out of head” listening experience that comes from listening to a stereophonic setup.

The audiophile has become the resident expert in stereophonic listening. They use expensive equipment, careful positioning of the speaker and listener positioning and the acoustic conditioning of the listening room. Here, we certainly won’t be going that far but we’ll still create that fantastic stereophonic listening experience right there in front of your computer screen.

Equipment needed: A computer, 2 small computer speakers, computer screen, big rubber band. Download or stream some pleasant, familiar 2-channel music that isn’t musically distracting or particularly engaging. Play the music through a pair of small separate computer speakers. Make sure you have cleared all the wire tangles between the speakers and the computer, so your speakers are free to be moved around.

Part 1

Turn volume down a bit, enough so you can hold each speaker up close to each ear, right speaker to right ear and left speaker to left ear. This setup replicates the familiar headphone/earbud sound.

We know the sound is coming from the speakers/headphone/earbuds. But the sound doesn’t seem to be located in the speakers, it seems to be located in your head or coming in a space slightly above your head. This is called in-your-head imaging.

Steven Stone, an audiophile equipment and music reviewer, an expert listener, focused his listening skills on this topic in 2019. The article has a link given below. Initially, he observes, as we have, that the sound image seems to hover above just the head. But that doesn’t make sense to how life is experienced. He found that if he laid down on a bed, face up with his head toward the door, feet away from it, the sound seems to come from open doorway. I’ve also discovered this effect. Try it sometime, it really works.

Part 2

Move the speakers away from your ears, straight out to the side at full arm’s length, speakers are still pointed towards your ears. You will probably want to turn the volume back up. This sound isn’t so up close and personal as headphones but you are still having the headphone type of listening experience.

Part 3

Then quickly swing both speakers forward and stopping together directly in front of you, so they touch each while still facing you, while still held out at arm’s length. What kind of sound is this? It’s called mono.

It is like an old style radio that only has one speaker. The sound is coming from the two speakers you are holding right in front of you, and it sounds like exactly like that. The sound source (sound image) seems to be right in front of you, where the speakers are located.

So, we are noticing that with stereo speakers to either side of our head, the sound doesn’t seem to come from the speakers but instead from a location either in or just above our head. But with the same speakers located directly in front of us, we distinctly recognize that the sound is coming from the speakers located directly in front of us.

Part 4

Put the speakers down and wrap a big rubber band around the two speakers so they stay stuck side by side to each other. Now, pick them up as before, at arm’s length, straight out in front of you, still pointing towards you. Nothing has changed and again, you get a center stage mono image, which is the location of the apparent sound source.

Raise the speakers and what happens to the image? Lower them back down, even lower than before and where does the apparent sound source move to? Yes, up and down. Did you notice how your head and your eyes wanted to move up and down to track the speaker location?

Let’s recognize something else in our world of ear/eye coordination. We are sitting on a stool our in the woods. We hear a small twig snap off to the side, we immediately turn our head and eyes towards that place. We don’t have to look for where the twig is because our ears already told us where it is. Now we want to know what made the twig snap. Ah, nothing much, just a big bug.

Part 5

Back to the starting point with banded speakers held straight out in front. Without moving your head, transfer the weight of the speakers to your right hand and move your right hand a few inches out to the right. Where does the sound come from?

It still comes from wherever the speakers are located, in this case a little to your right, also known as audience-right (and at the same time, stage-left). Stage-left is to your left as you stand on stage facing the audience. Audience-right is to your right as you sit facing the stage.

Part 6

With the pair of speakers still held over to the right, raise them and notice how the sound source (located where the speakers are located) also raises. Lower the speakers and move the pair left and right slowly at the same time. The sound image remains glued to the speakers.

Head is still facing straight, swing the speaker arm around, let them fly around at the end of your arm and listen how well you can track where the speakers are located without even looking at them. It’s called “Echo location” which means to know where a sound is coming from without having to look at where it is coming from.

But the ear/eye coordination is much faster than this snap-then-look story. We might step into a room and immediately look at the faucet. Upon inspection we discover it was quietly hissing and a tiny amount of water was dribbling. We didn’t see it first with our eyes, we heard it as we walked into the room and unconsciously looked directly at the faucet as we entered the room. If we hear a sound source we visually know exactly where it is located without ever having to look at it.

To be continued…

Art Noxon, Sept 2016
Revised Feb, 2022