Audio Mixing (recorded Music) - Mixing in Surround

Mixing in Surround

Mixing in surround is very similar to mixing in stereo except that there are more speakers, placed to "surround" the listener. The same mixing domains mentioned above are involved, but instead of stereo's horizontal panoramic aspects, and depth's front-back aspects, mixing in surround lets the mix engineer pan sources within a much more two-dimensional environment. In a surround mix, sounds can appear to originate from any direction.

There are two common ways to approach mixing in surround:

• Expanded Stereo – With this approach, the mix will still sound very much like an ordinary stereo mix. Most of the sources such as the instruments of a band, the vocals, and so on, will still be panned between the left and right speakers, but lower levels might also be sent to the rear speakers in order to create a wider stereo image, while lead sources such as the main vocal might be sent to the center speaker. Additionally, reverb and delay effects will often be sent to the rear speakers to create a more realistic sense of space. In the case of mixing a live recording that was performed in front of an audience, signal recorded by microphones aimed at, or placed among the audience will also often be sent to the rear speakers to make the listener feel as if he or she is in the crowd.

• Complete Surround/All speakers are treated equally – Instead of following the traditional ways of mixing in stereo, this much more liberal approach lets the mix engineer do anything he or she wants. Instruments can appear to originate from anywhere, or even spin around the listener. When done correctly, interesting sonic experiences can be achieved, as was the case with James Guthrie's 5.1 mix of The Dark Side of the Moon.

Naturally, these two approaches can be combined any way the mix engineer sees fit. Recently, a third approach, or method of mixing in surround was developed by surround mix engineer Unne Liljeblad.

• MSS – Multi Stereo Surround – This approach treats the speakers in a surround sound system as a multitude of stereo pairs. For example, a stereo recording of a piano, created using two microphones in an ORTF configuration, might have its left channel sent to the left rear speaker and its right channel sent to the center speaker. The piano might also be sent to a reverb having its left and right outputs sent to the left front speaker and right rear speaker, respectively. Additional elements of the song, such as an acoustic guitar recorded in stereo, might have its left and right channels sent to the left front speaker and the right rear speaker with a reverb returning to the left rear speaker and the center speaker. Thus, multiple clean stereo recordings surround the listener without the smearing comb filtering effects that often occurs when the same or similar sources are sent to multiple speakers.