MSB Technology DAC II User Manual

SIGN MAGNITUDE LADDER DAC SPECIFICATIONS

DAC II

Preamp

Users

Manual

Rev 1 (1/03)

INPUTS:COAXIAL, TOSLINK, BALANCED

AES/EBU, 2 MSB NETWORK
(192K) AND A BALANCED
ANALOG INPUT

RCA OUTPUTS: 3.6V RMS (10Vpp)
OUTPUT IMPEDANCE: 50 OHMS AT 0dB
BALANCED OUTPUT: 7.5 V RMS (20Vpp)

VOLUME CONTROL:2 dB STEPPED ATTENUATOR (32

STEPS)

SAMPLING FREQUENCY: 1.5 MHZ UP TO 5 MHZ
DIGITAL FILTER:8 TIMES OVERSAMPLING
SLEW RATE: >1000 V/MICROSECOND
SETTLING TIME: <90 NANOSECONDS
DYNAMIC RANGE: 136 dBA MEASURED
NOISE FLOOR: < -145 dB
THD+N: .002
SIGNAL TO NOISE RATIO: 140 dB
CHANNEL SEPARATION: >130 dB
CONTROL FEATURES:REMOTE

DISPLAY DIM MODE
PHASE INVERT
FILTER OPTION
UPSAMPLING
VOLUME AND INPUT SELECT

DAC II Preamp Users Manual

Rev 1 (1/03)

Unique Product - a Preamp or a DAC?

This product is a unique combination of a very high performance DAC and the ultimate passive preamp. It is intended to be used as both
for the best possible sound in your system. Our preamp philosophy is based on the belief that from the moment analog audio is created,
every transition that is made degrades the quality. That means that an active preamp with many stages if perfect would have no effect and
any imperfection would result in degradation of the music. That is why we have used a passive preamp within the DAC II, to achieve the
simplest, shortest possible signal path, with the least possible degradation of the true music.

The Preamp Upgrade

The DAC II Preamp has just one analog input and many digital inputs. It is designed to be the last
component in your system before the amplifiers. With its incredibly low impedance, especially
for a passive preamp, it can drive long interconnects and handle any type of amplifier input stage
design with optimum performance.

Depending on how many analog sources you have in your system, you may be able to eliminate
your current preamp. If you currently have only CD and vinyl in your system, you would attach
your CD players digital output to the DAC II and the output of your phono preamp to the analog
input. Your system is now complete, with the shortest possible signal path and the best sound
you can achieve. The same idea applies to use with an SACD player. Since SACD does not come
out the digital output, the analog SACD is attached to the analog input on the DAC II and the
digital output for CD playback.

If you have a complex system with a preamp with many analog inputs, attach the outputs of your
preamp to the input on the DAC II. Shift any digital sources over to digital inputs on the DAC II
and again, you will achieve optimum results. Set your preamp to a volume that matches the DAC
II output and use nothing but the DAC II volume control in your system.

Setup and Quick Start

CD or DVD-A

Transport

Digital

Phono

Preamp

Analog

DAC II Preamp

Analog

AMPs

The front panel is quite simple with few user controls. Set the input source to auto and
start with all the other options off (No LED lit). On power up, the volume is reset to -62 dB.
Turn the volume knob up until you hear music.

Power - The Platinum comes standard with an inboard power supply. A switch on the
back allows the unit to be switched between 240V and 120V. Please check your setting
before plugging the unit in. Leave the Platinum powered on all the time.

Inputs - The Platinum comes standard with two MSB Network (CAT5), AES/EBU balanced,
coaxial and optical digital audio inputs, as well as a balanced analog input, ranked in
order of performance. Connect any digital input to any active digital audio source. The
frequency of the incoming signal will be read out on the front panel and analog audio will
be found on both balanced and single-ended analog outputs.

Outputs

Connect the balanced or single-ended analog outputs to any amplifier and audio should
be present. The output level is controlled with the knob or remote.

Burn-In

The concept of burn-in is little understood. Does it take your ears some time to get used to the incredibly detailed and life like sound of
an MSB product or is something actually changing? The feedback we receive leads us to recommend at least 100 hours of burn-in on this
DAC. Customers generally recommend one month.

Digital

SACD Player

Analog

DAC II Preamp

Analog

AMPs

2

Unique Technology - the past and the future

Over 10 years ago early DACs were all 16 bit ladder DACs, with a precision laser­trimmed 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

MSB DAC Module (Non-inverted signal)

23 bit positive sign DAC

23 bit negative sign DAC

MSB DAC Module (Inverted signal)

23 bit positive sign DAC

23 bit negative sign DAC

Right Channel

Coaxial Out

Balanced Out

BLOCK DIAGRAM

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 non­inverted 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 re­clocks 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

3

4X

UPSAMPLING

ON

SIGN WAV E (0DB, 19.95 KHZ TEST TONE

SCOPE SETTINGS 2 V/DIV, 10USEC/DIV)