Camco Q-Power - Manual (Page 17)

4 OPER
ATION
USER MANUAL
Q - P O W E R S E R I E S P. 6
Q - P O W E R
S E R I E S
4.2 Controls
4.2. Volume Control
A volume control with 4 notched settings controls the audio signal. These
settings have been selected to correspond to human hearing characteristics
(logarithmically) and therefore guarantee an optimal range of settings for
practical applications. Each channel can be set individually.
Set the volume to zero before turning on the amplifier to prevent the occur-
rence of sudden high volume levels which may cause damage to your hearing
and/or the speakers.
4.2.2 Gain Selector
A switch on the rear of the Q-POWER amplifiers allows the maximum amplifica-
tion attainable to be set directly in the input stage.
The Q-POWER amplifiers have a 26 dB and 32 dB
voltage gain setting along with a ,4 V sensitivity
setting.
4.2.3 Limiter Switch
This switch is located at the rear of Q-POWER amplifiers. It allows you to activate
the clip limiter function on the channels A/B and C/D respectively.
4.3 Power Amp Protection Systems
4.3. Clip Limiter
If the power amp is overdriven and the limiter is set to on (see section 4.2.3)
the clip detection triggers the Attack-Release-Circuit (ARC). The ARC delivers
the control voltage for the gain reduction.
4.3.2 SOA Protection
Whenever the power transistors leave their Safe Operation Area (SOA), the SOA-
protection will either switch back the current rail of the respective channel
(Q-POWER 4 & Q-POWER 6) or limit the maximum load current in the power
transistors (Q-POWER 10).
4.3.3 DC Protection
Each output of the power amp is constantly monitored for persistent DC voltage
levels. If the 3 V thresholds are exceeded at any of the outputs, the correspond-
ing channel will be muted. If DC was only applied for a short moment, the ampli-
fier will release mute and work as normal. If DC is applied for longer periods or
several short times the amplifier will switch to standby mode.
Switch off the amplifier, wait until all indicator LEDs extinguish and switch the
amplifier on again.
4.3.4 DC Servo
To prevent DC Offset at the speaker output the Q-POWER amplifiers are fitted
with a DC Servo.
4.3.5 Over Current Protection
Over current is permanently controlled in the output stage. In case of exessive
loading the maximum output current of the amplifiers is automatically limited.
This improves reliability without degrading sound quality when driving com-
plex loads.
4.3.6 Thermal Protection
There are sensors in each amplifier heatsink in order to ascertain temperature
data. If a temperature of more than 85 °C is detected at the heat sinks, the input
signal on that channel is reduced proportionally to prevent further heating of
the amplifier. If the temperature exceeds approximately 00 °C, the main SMPS
is switched off(safety shut-off).