Non-Standard Panning

Standard amplitude panning has advantages and disadvantages. It is conceptually simple, and it definitely works over a large audience area at the "cardinal" points, that is, if a sound is panned hard left all audience members will perceive it as at the left loudspeaker. Panning halfway between channels leads to some problems, as moving around

the listening area will cause differing directional impressions, due to the precedence effect described in Chapter 6. Beyond conventional amplitude panning are two variations that may offer good benefits in particular situations. The first of these is time-based panning. If the time of arrival of sound from two loudspeakers is adjusted, panning will be accomplished having similar properties to amplitude panning. Second, more or less complete HRTFs can be used in panning algorithms to better mimic the actual facts of a single source reproduced in between two loudspeakers. If a sound is panned halfway between left and left surround loudspeakers, it is often perceived as breaking up into two different events having different timbre, because the frequency response in the listener's ear canal is different for the two directions of arrival. By applying frequency and time response corrections to each of the two contributory channels it is possible for a sound panned between the two to have better imaging and frequency response.The utility of this method is limited in the listening area over which it works well due to the requirement for each of the channels to have matching amplitude and time responses. One console manufacturer employs HRTF and time-based panning algorithms and room simulation within the console and that is Studer.

Panning in Live Presentations

When the direct/ambient approach is used for programming such as television sports, it is quite possible to overdo the surround ambience with crowd noise, to the detriment of intimacy with the source. Since the newly added sensation the last few years is surround, it is the new item to exercise, so may be overused. What should not be forgotten is the requirement for the front channels to contain intimate sound. For instance, in gymnastics, the experience of "being there" sonically is

basically hearing the crowd around you, with little or no sound from the floor. But television is a close-up medium, and close-ups, accompanied by ambient hall sound, are together a disjointed presentation. What is needed is not only the crowd sounds panned to the surrounds, but intimate sound in front.The crowd should probably appear in all the channels, decorrelated by being picked up by multiple microphones. Added to this should be close-up sound, probably shotgun based, usually panned to center, showing us the struggle of the gymnasts, including their utterances, and the squeak and squawk of their interfacing with the equipment. In this case, the sense of a stereo space is provided by the ambient bed of crowd noise, helping to conceal the fact that the basic pickup of the gymnasts is in fact mono. In a live event, it is improbable that screen direction of left-center-right effects can be tracked quickly enough to make sense, so the mono spot mic. plus multichannel ambience is the right combination of complexity (namely, simple to do) and sophistication (namely, sounds decent) to work well.

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