MSB Technology DAC II User Manual
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Unique Technology - the past and the future
Over 10 years ago early DACs were all 16 bit ladder DACs, with a precision laser-
trimmed resistor creating the appropriate analog level for each of the bits. The DACs
worked well and sounded good. They were quite expensive as very accurate resistors
were required. Then along came the “single bit” DACs. Rather than using a resistor to
create an analog level, pulse width modulation was used. Basically each bit was created
by turning a switch on and off for the appropriate length of time. The resulting square
wave pattern was filtered to create a smooth output. The expensive resistors were
gone, and so was the good performance. Next came the Delta Sigma DAC. It used the
same pulse width modulation but rather than creating a single large pulse for each data
point, the data point was created with many small pulses. This allows the pulses to be
smoothed with a less radical filter, and improves the sound. As you can see, upsampling
the input signal to a higher frequency reduces the filtering requirements and thus
improves the sound. This is the current state-of-the-art as exemplified in the LINK DAC
4.
The Platinum draws from the older, superior ladder technology, but with incredible improvements. The Platinum contains four 24 bit MSB
DAC modules (seen below). The Platinum is fully balanced so there is a matched pair of 24 bit DAC modules for the inverted and non-
inverted signals on each of the right and left channels. Finally, each DAC module contains one R2R ladder DAC with a 23 bit negative sign
and one R2R ladder DAC with a 23 bit positive sign. Together this makes a true 24 bit DAC. This design allows the quieter moments in your
music to be true to the music, without the linearity errors near zero that plague normal ladder and delta-sigma DAC designs. With a dual
24 bits of combined resolution, a 24 bit source gives a true 24 bit resolution without the losses and errors that make your normal 16 or 24
bit DAC perform far less than their actual resolution (normal 16 bit DACs only muster a meager 12 bits of resolution). The Platinum is
carefully designed so as to require no DC correction in the output stage. This allows direct DC coupling on the output stage for pure,
uncolored sound -- with no output filtering to
muck up your high end or smear your bass
attack. And for those who require a balanced
analog output, the separate positive and
negative DACs directly drive the balanced
outputs, with no analog output stage at all!
Another major difference in the Platinum is
the type of output. Essentially all ladder
DACs produce a current output. This is
converted to a voltage output with a current
to voltage converter. This problematic circuit
colors the sound and introduces non-linearity.
The Platinum is a true voltage DAC with a
voltage output right from the source. All
amplifiers have slew rates greater than 1000
Volts/microsecond. The output impedance of
the Platinum is 50 ohms.
Front Panel Features
The DAC II has 4 control buttons on the front panel, a knob and a display. The buttons toggle on and off. When on, the LED next to the
button is lit.
Upsampling and filtering
The MSB Platinum grants the user the ability to upsample from ANY lower audio standard
to four times the rate, but limited to 24bit/192kHz (so CD is upsampled to 176.4k and
everything else is 192k). This is a selectable feature and may be turned off. To play a 24/
192 disc the Platinum only needs to be plugged into a DVD-A player with an MSB Network
output. This upsampling feature
also dynamically buffers and re-
clocks all the data and clock signals
to provide a virtually jitter-free
source directly to the DACs.
The selectable digital filter response
permits the user to choose the filter
design they prefer. It allows for the
selection of a standard brick-wall
filter or a slow roll-off filter, both at
half the sampling frequency. Each
provide a distinct, glorious listening
experience. You may favor one or
the other, or enjoy changing the
filter response to suit the music you
Balanced Out
MSB DAC Module (Non-inverted signal)
23 bit positive sign DAC
23 bit negative sign DAC
23 bit positive sign DAC
23 bit negative sign DAC
Coaxial Out
MSB DAC Module (Inverted signal)
B
LOCK
D
IAGRAM
Right Channel
S
IGN
W
AVE
(0
DB
, 19.95
K
H
Z
TEST
TONE
S
COPE
SETTINGS
2 V/
DIV
, 10
USEC
/
DIV
)
4X
U
PSAMPLING
O
N