USING THE 70/ 25 VOLT AMPLIFIER IN MONO MODE
For Stereo Operation with the Rear Slide Switch in the Stereo Position, the Amplifier will provide 22 1/2 watts to the
Left Zone and 22 1/2 watts to the Right Zone Output.
70V / 25V AMPLIFIER
The Amplifier can provide 2 Separate Zones IN and two Separate Zones OUT or the two Zones can be
combined to provide either Mono or Stereo Mode depending on where the Slide switch is positioned.
With the Rear Slide Switch set to Mono, there are two MONO possible configurations, either to two Zones each providing 22 1/2
watts Output , or paralleling the two Outputs for a total of 45 watts. Either of the Zone Input can be used, and each is controlled by the
corresponding Volume Control.
USING THE 70/ 25 VOLT DUAL ZONE AMPLIFIER IN STEREO MODE
SLIDE SWITCH
TWO ZONE INPUTS 1 & 2
ZONE1
SINGLE ZONE MODE
STEREO OR MONO
TWO ZONE MODE
ZONE 1 OUT
ZONE 2 OUT
COM
COM
COM
ZONE2
SINGLE ZONE MODE
INPUT MODES
PLEASE NOTE
In the event only 1 Zone is being used, the unused Zone
Volume Control should be set to Zero.
AUTOMATIC FAN CONTROLTURNS FAN OFF
WHEN NO AUDIO SIGNAL IS PRESENT
70/25 VOLT OUTPUT
We use Custom Made Autoformers in place of Transformers to give the best possible 70/25 Volt Amplifier Output.
In selecting the Transformers for the Speakers, determines the quality of the Speaker Output, therefore we suggest
using the highest grade of Speaker Transformers when sound quality is paramount.
POWER SUPPLY
An AC Power Supply must be used - Part # NB-PS75
110V - 12V 4.5 Amps AC
Our NB-PS75 is UL/CSA Listed
DUAL ZONE
Part # NB-70AMP
See other side for Installation Options
INSTRUCTIONS
Requires NB-PS75 AC Power Supply
ADC
THRESHOLD ADJUSTMENT
(FACTORY SET)
ADC ENABLED
POWER INDICATOR
The Threshold Adjustment is factory set, and should not need adjust-
ment, unless the Threshold Indicator does not light up.To Adjust, with
Sound playing, turn the Pot slightly until the LED lights up
ENERGY EFFICIENT AMPLIFIER TURNS ON & OFF AUTOMATICALLY
Turns on within 2 milliseconds on hearing Audio and Turns off after 30 seconds if Audio is not being detected
AMPLIFIER TURNS ITSELF ON AND OFF
AUTOMATICALLY TO CONSERVE ENERGY
AUTOMATIC DETECTION CIRCUIT