18
Nagra –
TUBE DAC
Line mode
The TUBE DAC can operate as a pure D/A converter connected to an external
preamplifier or an integrated amplifier that both possess their own volume
control. In this case, you should have a fixed output level: DIRECT (the signal
won’t pass through the TUBE DAC potentiometer, and no control is possible).
Should you wish to use the TUBE DAC built-in volume control, you should select
a tunable output level: VARIABLE.
You may select DIRECT or VARIABLE, it will not affect the headphones amplifier
level, the latter will always go through the volume control potentiometer
allowing the playback level to be adjusted. To select the mode, go to:
AUDIO SETTINGS
Press the Controller knob to
enter into the AUDIO SETTINGS
menu and rotate it to select LINE
MODE.
-- LINE MODE ---
VARIABLE
By
default,
VARIABLE
is
selected, as shown here.
To change the mode, press the Controller knob and select VARIABLE or DIRECT
by rotating it, then confirm by pressing once again the Controller knob, the new
desired LINE MODE is stored.
Note
When you change the setting from VARIABLE to DIRECT, the TUBE DAC will be
muted, a blinking
D
will appear on the right down corner of main display. This
is just to remind you that you are now in DIRECT mode, the signal will be at full
AES
NO SIGNAL
D
level. If you have changed this
setting by accident, there is time to
come back to VARIABLE before
damaging your hearing or your
speakers!
When you change the setting from DIRECT to VARIABLE, the TUBE DAC will be
muted, a blinking
X
will appear on the right down corner of main display. This
AES
NO SIGNAL
X
is just to remind you that you are
now in VARIABLE mode, the signal
level will be adjustable with volume
control potentiometer.
If the optional symmetrical output transformers are installed into your
TUBE DAC, the VARIABLE mode does not work any longer.
WARNING
With DIRECT line mode selected:
- Before 1.03 software version, at power ON, audio
output is
muted
.
- Since 1.03 software version, at power ON, audio
output is
NOT muted
any longer. Be careful with audio
output level not to damage your hearing or your
loudspeakers!
