Instruction manual

DAC1 HDR Instruction Manual Rev I Page 20
Headphone Switch Disable (JP1
and JP2):
The DAC1 HDR is configured so that the
analog outputs will mute when a headphone
plug is inserted into the left-hand jack. This
is convenient when the user wishes to switch
between headphones and speakers. This
feature can be defeated by adding jumpers at
JP1 and JP2.
JP1 and JP2 should be configured as follows:
•
Headphone Switch enabled*** (Jumpers
Removed)
•
Headphone Switch disabled (Jumpers
Inserted)
Photo 2 – Headphone
Switch Disable (JP1 and JP2)
Headphone Gain Reduction (JP3
and JP4):
The gain range of the HPA2™ can be set
using jumpers JP3 and JP4. When jumpers
are installed at position “A” the headphone
amplifier gain is decreased by 20 dB. When
jumpers are installed at position “B” the
headphone amplifier gain is decreased by 10
dB.
The ideal gain setting permits the user to set
the front-panel Volume Control above 40%
(10 o’clock) without the headphone volume
being too loud.
JP3 and JP4 are factory installed at position
“B” to reduce the headphone output by 10
dB. This setting is best for most applications.
Remove the jumpers if you need more gain,
or move them to position “A” if you need less
gain.
Photo 3 – Headphone Gain Reduction
(JP3 and JP4)