Instruction manual

DAC2 DX Instruction Manual Rev A Page 14
feel, and convenience of an analog control while providing the accuracy, transparency, and
precision of 32-bit digital control.
MUTE Function
The MUTE function mutes all analog outputs. The MUTE function does not mute the DIGITAL
PASS-THROUGH.
DIM Function
The DIM function fades all analog outputs to a level that is 20 dB lower than normal. This feature
is intended to provide a convenient means to fade to and from a temporary background level
without changing the volume control setting. DIM should not be used for normal listening. If DIM
is required to achieve a normal playback level, this is an indication that the OUTPUT
ATTENUATORS are set incorrectly (add more attenuation to fix this problem).
Volume-Control Bypass (Calibrated Output Level)
The volume control bypass function sets analog outputs to the maximum volume (BYPASS mode).
In this mode, the 32-bit digital attenuator is bypassed and a full-level output signal is passed to the
analog outputs. This is useful when volume is controlled before or after the DAC2.
HPA2™ "Zero-Ohm" Headphone Power Amplifier
The HPA2™is one of the most transparent headphone amplifiers available. It also is able to deliver
high current and/or high signal levels. This makes it well suited for cleanly driving virtually any set of
headphones. The near 0-Ohm output impedance provides outstanding damping of headphone
drivers. This damping reduces distortion, and maintains precise control of the frequency response.
Headphone Mute Switches
The left-hand headphone jack mutes the MAIN analog outputs. In contrast, the right-hand
headphone jack allows simultaneous use of the MAIN outputs and headphones. The left-hand jack
provides automatic switching between loudspeaker and headphone monitoring. The right-hand jack
allows simultaneous use of loudspeakers and headphones.
On the DAC2 DX, either or both headphone switches can be enabled or disabled using internal
jumpers. The switches and jumpers control logic-level signals, no audio passes through these
components. By default, the switch function is enabled on the left-hand jack but disabled on the
right-hand jack.
The high-power HPA2™ headphone amplifier can easily drive two sets of headphones
simultaneously. Both headphones should have similar voltage sensitivities.
Direct Interfacing to Power Amplifiers
All Benchmark DAC1 and DAC2 converters are designed to directly drive power amplifiers and
powered studio monitors. For best performance, no additional devices should be inserted between
the DAC and the power amplifier. A direct connection between the DAC and the power amplifier