The ORTF technique blends coincident and spaced microphone characteristics

Evidence

There also exist methods, such as the ORTF technique, that can be classified as falling this technique between the coincident and spaced microphone techniques. In it, two cardioid microphones are positioned 17 cm apart with an angle of 110◦. The captured signals may thus differ both in time and in amplitude. At low frequencies, the system corresponds to the XY cardioid technique, since the distance between the microphones is small compared to the wavelength. At high frequencies, the microphone signals have considerable phase differences. The perceptual attributes of the reproduced virtual sources and reverberation are reported to be somewhere between the attributes of the coincident and the spaced techniques (Lipshitz, 1986). — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 1847

Categorization

• DEFINE: A clear technical definition of the ORTF microphone technique and how spacing/angle trade off time vs. amplitude differences.