Audio Developments AD149 - Manual (Page 10)

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and ambience, whereas recordings made with X-Y techniques can suffer from centre-
stage high-frequency deficiency caused by the off-axis degradation of HF response of
many directional microphones. Critical and discerning listeners are aware of the
image shifting with changing frequency caused by less-than-perfect microphone polar
patterns or the use of unmatched pairs of microphones. These same listeners will
also be disturbed by the phasing effects caused by the movement across the faces of
badly positioned 'spot' or highlighting microphones, and by the fact that images at low
frequencies are often narrower than those at high frequencies.
In view of the narrowness of the angle subtended by a TV or cinema screen at a
typical viewing position, "Why stereo?" is a question frequently asked. "Why not?" is
the reply more frequently being given - even stereo dialogue is becoming increasingly
common. Advantages of stereo include a more accurate portrayal of the local
acoustic, separation of voices with space and air between them, correct placement
and perspective of locally occurring sounds and sound effects.