DELAY
(One of these switches must be selected. If all the switches are OFF, there will be no output signal.)
The delay feature provides five sections of 2nd-order all-pass delay filters of 450µsec +/-10µsec each. Unlike the more commonly used 1st-order all-pass, the 2nd-order filters achieve a constant delay time over the usable frequency range of 1Hz to 1kHz. At frequencies higher than 1kHZ, the gain remains flat, while the delay time gradually decreases to zero.
The delay time is labeled in inches of delay (i.e. 450µsec/section X 1130ft/sec X 12 inches/ft = 6 inches/section). If there is uncertainty about the amount of delay needed, choose the 0” switch.
CD HORN EQUALIZATION
This adjustable high-frequency shelving circuit can be used to compensate for the roll-off of constant directivity (CD) horns. At the +10dB setting, the gain increases with frequency to about +3dB at 3kHz, and finally to +12dB at 20kHz.
+10dB
6
2
CROSSOVER
A 3-position slide switch selects the High-Pass (HP), Low-Pass (LP), or Full-Range (Full) configuration of the 4th-order crossover.
FREQUENCY
The crossover frequency can be selected as either 500Hz or 800Hz.
PHASE
The Phase switch will select either 0° (normal polarity) or 180° (inverted polarity) for the corresponding output signal.
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