The Channel Amplifier operates from a Microphone or Line source and raises the level of the incomming signal to 0 dBm for feeding into a 600 ohm load. The following frequency response correction operations are carried out and controlled by the channel amplifiers.
Presence (mid frequency cut/boost).
Low frequency cut/boost.
High pass filter.
The level of the incoming signal can be between -80 dBm and -20 dBm for a microphone input, or between -20 dBm and +10 dBm for line input. After amplification and signal processing the output level is 0 dBm.
The module contains two standard amplifiers BA284 and BA283 which are described seperately.
mic sensitivity in 5db steps range between -80 and -20
line sensitivity in 5db steps range -20 to +10
treble control is stepped at 10 kHz
mid range frequencies are stepped; 0.7, 1.2, 2.4, 3.6, 7.0 kHz
bass frequencies also stepped; 35, 60, 100, 220 Hz
high pass filter frequencies range 45, 70, 160, 360 Hz
the EQ is switchable; in/out and there is a phase switch