14
3
Introduction
Thank you for purchasing B.M.C.'s DAC1 and congratulations for choosing this exceptional component!
We also like to thank you for supporting the puristic SUPERLINK interconnection system by this
purchase.
It makes more sense and thus it is easier to reduce jitter when having the "Master‐Clock" inside the
Digital to Analogue converter, just the way SUPERLINK is doing. The separate transmission of the
"Master Clock", "Bit Clock", "Left‐Right Clock" as well as the audio data also avoids degredations by
coding and later decoding such signals into a single stream, like SPDIF transmission is doing. As long
as your CD‐transport supports SUPERLINK this is the best interconnection to a DAC.
Additionally to the SUPERLINK concept sophisticated clock‐synchronisations for the digital audio signal
keep the signal quality on the highest level.
One key for the exceptional sound quality is the global‐feedback‐free analogue section. With its CI‐
input (CI = Current Injection) input the DAC‐chip get the optimum interface and the extremely fast
circuit is insensitive to digital noise, preserving all musical information. The LEF output driver delivers a
stable output signal, again without a sound degrading global feedback loop. LEF (Load Effect Free) is
a balanced, cascoded, single‐ended‐class‐A circuit with a separate delivery of signal voltage and
signal current.
With DAC1's DIGM‐controller feature it is possible to achieve a high‐end audio system with very short
signal path, by connecting a B.M.C. power amplifier via the fixed level outputs and adjusting the volume
by losslessly changing the power amplifier's gain through DAC1's volume knob. For high end audio
systems with digital sources exclusively the DAC1 handles all preamplifier functions.
Optionally an additional preamplifier module is available, featureing 2 RCA and one balanced XLR
analogue inputs in addition to the digital inputs. A balanced XLR output interconnects to power
amplifiers, active speakers or subwoofer. The preamplifier module offers two different operation modes:
‐ Traditional preamplifier function with volume control.
‐ Super short signal path for the use with DIGM amplifiers.
Content of Packing
DAC1
AC Power Cable
Remote Control H 2 AAA‐Batteries
Owner's Manual
It is recommended to keep the packing for eventual later transportations.
Attachment: Jumper Settings
For safety reasons only qualified service
personnel is permitted to change jumper settings!
Switch off the unit and disconnect the power
cable each time before changing the jumper
setting!
ORANGE: Loop‐Through Mode
For Loop‐Through Mode plug jumpers JP3, JP4,
JP5, JP6, JP13, JP14, JP15 and JP16.
Loop‐Through Mode is intended to be used for
connecting with an amplifier having an adjustable
volume. BMC amplifiers have a lossless gain
control, BMC power amplifiers can be controlled via
optical DIGM interface by this DAC1.
GREEN: PreAmp Mode
For PreAmp Mode with volume control inside this
module, plug jumpers JP1, JP2, JP7, JP8, JP9,
JP10, JP11, JP12, JP17, JP18, JP19 and JP20.
PreAmp Mode is intended for use with conventional
power amplifiers and active speakers.
BLUE: DC Mode
For DC Mode plug jumpers JP21, JP22, JP23 and
JP24.
These jumpers allow to DC couple the output of the
digital potentiometer. Without the jumper the output
is AC coupled.
AC operation may reduce "zipper‐noise" during
volume setting.
DC coupling is the direct pathway and thus offers
sonic advantages.
In Loop‐Through Mode, these jumpers have no
influence.
