Front Panel Features
Microphone/Line Level Controls
The 6 dual mic/line input controls are labelled Ch 1 through to Ch 6 and should be adjusted to provide the
required level mix for each individual channel. Start with the controls set to level 0 and turn the controls
clockwise until the desired mix level for each channel is reached.
Bass Control
Setting this control in the centre position will give an overall flat bass response. Adjusting the bass control
in a clockwise direction will provide up to 12 dB of bass boost @ 100 Hz. Adjusting the bass control in a
counter-clockwise direction will provide up to -12 dB of bass cut @ 100 Hz.
Middle Control
Setting this control in the centre position will give an overall flat middle response. Adjusting the mid
control in a clockwise direction will provide up to 12 dB of mid boost @ 600 Hz. Adjusting the mid
control in a counter-clockwise direction will provide up to -12 dB of mid cut @ 600 Hz.
Treble Control
Setting this control in the centre position will give an overall flat treble response. Adjusting the treble
control in a clockwise direction will provide up to 9 dB of treble boost @ 10kHz. Adjusting the treble
control in a counter-clockwise direction will provide up to -9 dB of treble cut @ 10 kHz.
Master Output Control
The Master level pot controls the overall output level of the amplifier depending on the levels set for the
individual input channels as detailed above. Start with the control set to level 0 and turn clockwise until the
desired output level of the amplifier is reached.
Power Switch
This switch controls the switching of AC power to the amplifier. A blue ‘On’ LED will indicate whether
the amplifier is switched on or off. This switch will not switch DC power on or off in DC operation. In DC
operation mode, the amplifier is always on and the blue power LED will always be illuminated.
Protect LED
A feature of the AMIS250 is high temperature protection. In most applications, the internal cooling fan will
most probably never switch on. When used with demanding speaker loads or in difficult operating
environments, the fan may regularly switch on to cool the amp down and then switch off again. This
switching on and switching off is quite normal. The “Protect” function is there to protect the amplifier from
a high temperature problems which would only occur if the fan stopped working or became clogged up. In
this very rare occurance, the amplifier will shut down and the protect LED will illuminate. The amplifier
will automatically restart once it’s internal temperature has fallen within “safe” limits. If the protect LED