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Boom Box Surround

With modern computers and audio interfaces, it is easy to achieve multi-channel audio. My notion of "Boom Box" surround is an affordable way to achieve surround sound using two existing portable stereos or even two home stereos. The idea is to immerse the listener in an environment using four speakers playing back four discrete channels (quadraphonic sound.) A typical, portable CD/Stereo unit has two discrete channels of audio. Therefore, in order to achieve quadraphonic sound, two portable stereo units are necessary. The result of this project is two stereo compact discs or two iphones connected to stereo speakers, each programmed for one of the two pairs of speakers. The tracks on the two playback devices should be identical in length, and started on their respective units in tandem.

The image below illustrates the use of panning to make a source sound "move." The process requires at least two stereo tracks in any audio editor. The top track (light blue) is programmed for the front left and right speakers. The illustration represents the use of panning through capturing automation to cause the sound to migrate between the left and right speakers. When the black line is at the top of the track, the sound travels to the left speaker and when at the bottom, to the right. This process is used on the bottom track (light green) to achieve the same type of movement in the rear left and right speakers. It would be nice to have the audio editor assigned to four independent channels via an audio interface to hear the effect; however, with a little imagination it is not necessary. In the illustration below, I have removed sections of audio to remove the sound from one pair of speakers while it is sounding in the other pair. Fades are utilized for smooth transitioning between the pairs of speakers. (more below...)



Use volume automation to cause the sound to move between the stereo pairs. The example below illustrates volume as a means to cause one track to "appear" at one pair, and then at another. The top track (light blue) represents a continuous region of audio with automated volume control. On the bottom track (light green,) a copy of the same region of audio is placed. The top track is intended for the front playback device, while the bottom track is for the rear playback device. While the volume automation is at maximum for the front track, it is kept at a minimum for the rear. Combining volume automation with panning automation is an excellent way to achieve movement with in the four speakers. On the top track, panning automation is represented in gray. (more below...)


Upon completing the project, select the entire composition and prepare to compile the multiple tracks into one stereo file. To engineer the content intended for the front playback device, mute the tracks intended for the rear playback device and "bounce" or export a stereo file. Then, without losing the initial selection, reverse the process by muting those tracks not intended for the rear playback device and export a stereo file. Keeping the overall selection the same for both "bounces" will ensure both media files for the front and rear playback devices are identical in length.

Finally, prepare to playback the media for the front and rear playback devices, stand in the middle, and press play at exactly the same time on both. Each unit should, although not synced to each other, play in tandem. If engineered correctly, sounds should appear to move around the listener's position.

Here are two example files, beesfront.mp3 and beesrear.mp3. Download them and play them back in tandem using two different playback devices connected to two stereo units.

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Last Modified:
January 19, 2017