| 摘要 |
A surround processor includes a time constant processing circuit for smoothing directional information signals from a detector with continuously variable time constants in order to generate one or more control voltage signals. The time constants produced by the circuit are continuously variable and responsive to both the rate of change and the amplitude of the directional information signals, such that as the difference between the controlled voltage signals and the directional information signals increases, the value of the time constants decreases to permit the control voltage signals to closely follow the directional information signals, and as the difference between the control voltage signals and the directional information signals decreases, the value of the time constants increases so that variations in the control voltage signals are smooth. Split-band processing of input audio signals to the processor is also accomplished without the necessity of placing filters directly in the audio path. A low-pass filter is utilized to separate out the low-frequency components of the input signals, and signal-dependent processing occurs with respect to the mid- and upper-frequency components only. Other improvements are also incorporated into the surround processor to optimize its performance. |
