Tuesday, December 19, 2006

Stereo vs. Mono. Is it worth it? By Anna Krutzik

For my test of different variables I chose to see if I could hear any difference between the three tests I had chosen as a good representation of stereo when I put them in mono. To my ears, all of the original tests sounded basically the same, with only very minimal variations on each other. While I could hear the stereo effects in the localization of the dings, not much else seemed to really make it "stereo" sounding. And the dings were sort of tempermental, you could tell the direction of some, but not completely all of them.

So, to test my ears, I compared the same tests in both stereo and mono and noticed an immediate difference between the two. In creating a sense of space, the stereo versions win hands down, the mono versions sounding flat in comparison. Of course, hearing the sound surrounding your ears (in stereo) rather than being duplicated into both ears the same (in mono) creates the feeling of actually standing in the room because it mirrors how a person would actually hear, each ear picking up on different sounds based on their positioning and putting them together to create a composite of the space.

As for the localization of the dings in mono vs. stereo, I didn't hear as much of a difference as I would have expected. For whatever reason, I could consistently hear more difference in the location of the dings between 1-4 in the stereo recording. I'm not quite sure if this is my own mind just subconsciously interperating the difference between hearing the dings from the left to the right side as thinking that the right side dings are more localized. Or if there is a specific technical reason for this. So in the mono versions of the tests, I didn't notice that much of a difference in hearing the dings on the left side.

I thought that maybe listening to the recordings in mono but still viewing the animations which illustrate where the ding is coming from in the clock positioning would fool my mind into thinking that I heard it the same as in stereo. And while it did a little bit, there was still an obvious difference when watching the animation and listening to the stereo version.

All in all, I now appreciate much more fully the value of stereo sound recordings and their ability to recreate and place the listener in the space of the original recording.

I recommend listening to the mono versions first and then to their stereo counterparts immediately after to get the full effect that the stereo brings.

Mono Versions
T4-07
T6-04
T9-02

Stereo Versions
T4-07
T6-04
T9-02

1 comment:

Rob D. said...

Hi Anna-

The "wrap" of the semi-chaotic low frequencies working different patterns on our left and right ears can be instantly recognized can"t it? Its one reason I often say that the background tracks can do the most "work" in a soundtrack if you'll give them a chance.

I agree with you that this low Hz "presence" is as important as the nail strikes to the stereo imagery we recorded. Its likely the low frequencies would be even more important after the machinery next door shut down and we made some low frequency sounds to test the stereo imaging of the room by the rigs.


Its fun to see how one tries to move the sounds around even with the mono track. I bet the urge would be even more pronounced if there was a single figure moving around the field- or a figure moving towards and away from the viewer and just change the foreground volume relative to a constant mono background. We've known how to create "space" in mono for many years.


I and several others agree with you that the imagining on the left side of the stereo field is far less defined. I'm guessing, and only guessing, that the simpler, open rectangular shape of the room behind the sounds on the right encoded the reflections on that side more informingly. The left side has intruding shapes-- some that create very efficent reflections and others that send the sound off in a whole new direction (like at 8). The sounds at 8 appeared to be coming from 12 in many tests. I also noticed that in many tests the "movement" from 12 to 1 was very pronounced. I can't explain this, but I suspect the orientation of the backwall behind 12 snd 1 was playing a big role.

I had a great time learming more stuff to think about when creating a Stereo image. You did a great job at keeping all of your channels open and staying ontop of your classwork. Best, Rob D.