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MSB 192 kHz POWER DAC
"The more you listen to it, the more you love it. This DAC seduced us with its two faces of musical reproduction: exceptional analysis capability and a warm and natural analog sense of music. The USB Power DAC knows how to make the emotion come true so very easily that we recommend it to any audiophile still reluctant with digital. "
Stereo & Image issue #15
* MUCH MORE DETAIL
* LESS HARSHNESS
* MORE DYNAMIC RANGE
* LOWER NOISE
* WIDER SOUNDSTAGE
* GREATER CHANNEL SEPERATION
* EQUAL TO OR BETTER THAN THE BEST (non-MSB) DACs, EVEN THOSE COSTING $50K
* BATTERY OPERATION COMPLETLY ELIMINATES POWER SUPPLY NOISE AND FLUCTUATIONS, AND INTERFERENCE WITH OTHER COMPONENTS
The MSB Power DAC - The Perfect Server Companion
The Power DAC has proven to be a reliable and solid product with unprecedented performance value. It is a very high performance DAC with sound quality similar to the Platinum DACs but with no user features. It runs for many hours on internal batteries with an external charger. It has no front panel controls, and no remote. A single digital input of each type is available with auto switching. The DACs are not modular so it does not accept Signature DACs. So what does it do? It gives you great sound at a great price with all the performance you expect from an MSB product. And because is runs on batteries, it is particularly well suited to working with computer servers.
High Resolution 192 kHz !
Inputs: Coaxial, Toslink, Balanced AES/EBU, MSB Network (192k)
RCA Outputs: 3.6V RMS (10V pp)
Balanced Outputs: 7.5V RMS (20V pp)
Output Impedance: 50 ohms at 0 dB
Sampling Frequency: 1.5 MHz up to 3 MHz
Digital Filter: 16x Digital Filter by MSB Technology
Slew Rate: >2500 V/Microsecond
Settling Time: <90 Nanoseconds
Dynamic Range: 136 dB A Measured
Noise Floor: <-145 dB
THD+N: .002
Signal to Noise Ratio: 140 dB
Channel Separation: >130 dB
Master Clock: +/- 2.5 ppm jitter
Control Features: Option toggle on back Software Updates
Unique Technology - the past and the future
Over 20 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 III with the upsampling option.
The Power DAC draws from the older, superior ladder technology, but with incredible improvements. The Power DAC has two 24 bit
MSB DAC’s built-in. Each DAC contains one R2R ladder DAC with a 23bit negative sign and one R2R ladder DAC with a 23bit
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 12bits of resolution). The Power DAC 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 Power DAC 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 Power DAC is a true voltage DAC with a voltage output right from the source. All amplifiers have slew rates greater than 2500
Volts/microsecond. The output impedance of the Power DAC is 50ohms.
Upsampling and filtering
As MSB technology has developed, so has our DAC architecture. Our advanced digital filter now replaces the asynchronous upsampling
of earlier models. The 16X Digital filter goes way beyond our older 4X upsampling. To play a 24/192 disc the Power DAC only needs
to be plugged into a DVD-A player with an MSB XPORT output. The new upsampling feature 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 listen to. Music with less high frequencies may
benefit from the slow roll-off filter.
To play a 24/192 disc the source player needs to have an MSB Network or XPORT output. If your DVD-A player does not have the
MSB Network output, it can be added. A 192k input will override the upsampling settings.
Custom MSB Digital Filter
The Power DAChas a custom DSP based Digital filter and clock module. We have created our own Custom Digital Filter for the MSB
DACs. Previous versions of the our DACs used the Burr-Brown DF704, which at the time was the best Digital Filter on the market.
Our Digital Filter is built to our specifications and standards, and is designed to get the most out of the Power DAC.
The performance of this Digital Filter is amazing. Immediately you’ll notice the lack of fuzziness
around voices and instruments of all frequencies. This filter also dramatically increases the resolution
and dynamics of the machine. This filter is also completely customizable; By playing a special .wav
file on a CD new filter coefficients, either temporary or permanent, can be loaded into our DSP.
The Digital Filter is a 16x oversampling, single stage filter with 32 bit input resolution, 80 bit computation, and 36 bit coefficients.
About the Clock / Jitter Control
Jitter control devices (and inputs on most DACs) normally reclock the input signal in attempt to lessen
the jitter of that incoming signal. The Power DACdoes no such re-clocking. We actually pay no attention to the clock on the input signal. All internal clocks are generated by an extremely accurate
+/- 2.5 ppm temperature compensated clock. Since the input clock is no longer related to the clock of
the Power DAC, an intelligent ½ second buffer is used to maintain data synchronization.
The MSB 16x Digital Filter is an ultra high-resolution digital front end. The combination of a highspeed on-board computer and carefully optimized software and hardware result in the best possible
music quality. During the development of this peerless digital audio system MSB has accumulated a
wide body of unique knowledge allowing us to design the ultimate digital filter.
More About the Digital Filter
One of our primary goals at MSB is to provide the music lover with the most accurate musical experience possible. During years of
careful design and improvement of our custom discrete DACs, which form the heart of your Power DAC, we realized that the Power
DACs sound quality was no longer limited by them. We soon narrowed the problem to the Digital Filter which was feeding our DACs.
While the excellent Burr-Brown (Now owned by Texas Instruments)
DF1704 Digital Filter had served us well in the past, it had became
the bottleneck once we started using our new Second Generation
DAC modules. After a thorough search of all the available off the
shelf and custom DSP based Digital Filters we realized that little
improvement could be had from any of them. With no other option
in sight we decided to build our own solution.
Converting the ones and zeros of Digital Audio into music is an
enormously delicate and critical process. Each individual sample
that makes up the audio stream must be converted into the high
resolution, continuous analog voltage that can be transformed into
the sound that you hear. Any misstep can corrupt the final result
ending with audio that does not sound anything like the original
recording. Errors in translation can make a harsh, veiled, muddy,
and/or tonally colored result. Minimizing each potential problem
allows the original recording to shine through.
Audio reproduction starts when the DAC receives the binary coded
information from the source. The first step requires recovering the
audio samples, which represent the final output voltages, and the timing, which tells the DAC when to output those voltages. Next the
sample rate is raised and the data is digitally filtered. While it is possible to feed the DAC with the original audio samples thereby avoiding the use of a digital filter skipping this step has many unintended consequences. After being digitally filtered the digital stream is feed
to the DAC. The DAC receives the digital audio samples and converts them into a continuous analog voltage. The best DACs, such as
our Second Generation DAC Modules or Signature DAC Modules, instantly convert the data into a precise continuous voltage waveform
with timing determined by the DACs conversion clock.
The digital filter is necessary because mirrored image frequencies created during the conversion process must be removed. If the DAC
did not have a digital filter, an analog filter with an aggressive response must remove these image frequencies. These brick wall analog
filters seriously damage the signal by corrupting the original phase of the sound and cannot fully remove the high frequency images. This
results in harsh or rolled off high frequencies and poor soundstage focus.
Traditional digital filter designs consist of cascaded FIR (Finite Impulse Response) filters, each of which raise the sample rate by two.
The intermediate data between the filters is usually stored at less than 40 bit resolution. Since the next filter works with previously computed data the resolution decreases with each filter pass. This limits higher quality digital filters to a low oversampling rate (usually 8x)
before the output starts to deteriorate. The loss in resolution is typically not apparent when using the best conventional digital filters with
standard DAC chips, but in combination with our high resolution 14 bit Second Generation, or Signature DACs the problem is very apparent. The sound becomes muddy, veiled and un-involving when using any off the shelf digital filter. To counter this problem the MSB
16x Digital Filter does it’s filtering in one filter stage that raises the sampling rate by 16.
FIR filters operate by multiplying each sample in the data by a set of filter coefficients and then summing the result. Most digital filters
round the result of each addition before the adding next sample. This repeated roundoff results in a similar problem to the cascaded x
filter approach, muddy sound. MSBs digital filter uses bit perfect accumulation in an 80 bit accumulator completely eliminating these
debilitating roundoff errors. Only as the last step do we carefully convert the audio to the 24 bits our DACs require. The high sampling
rate of the output allows us to include advanced ultrasonic dither and noise shaping techniques in this step to achieve greater than 14 bit
effective resolution.
Through extensive listening tests we have found that the choice of filter coefficients has a great impact on the tone of the music. We have
found that steep, phase perfect “Brick Wall” filters tend to sound the most neutral but are also the most difficult to implement without
problems. Improvements we have made in our digital filter, with its single stage design and 80 bit computation, allow us to use very
steep filters with no compromises.
Clock Jitter
The timing of the DACs conversion clock also has a large impact on sound quality. Any periodic frequency change or “jitter” causes a
loss of focus in the reproduced audio. The high power and large memory space of the SHARC DSP we use allows us to offer a unique
Ultra Clock to your MSB 16x Digital Filter. The Ultra Clock adds two ultra precision, ultra low jitter TCXO oscillators and custom clock
handling circuitry to your board. This custom circuitry allows us to do much more than simply reclock the data, as other jitter reduction
boxes do, but completely replace the incoming clock!
Most jitter reduction schemes rely on Phase Locked Loops or Asynchronous Sample Rate Converters. The Phase Locked Loop is able
to reduce jitter to a significant degree but not eliminate it because the output clock must be related to the input clock. The Asynchronous
Sample Rate Converter, which completely replaces the data and clock, seems ideal until you realize that the complex computation in
volved harms the data by permanently imbedding a portion of the clock jitter into the data. Sample Rate conversion is also detrimental
to the sound due to the complex and sub optimal digital filters involved, which must change their filter response to track minute changes
in the input to output clock ratio.
The Ultra Clock sidesteps both of these problems by storing the incoming data in an extremely large buffer (1/2 second of audio.) The
on-board clock then reads out the data without jitter. The on-board clocks are totally independent from the input clock so that no jitter is
transferred to the output. True absolute digital silences such as a track skips are selectively shortened or lengthened by the DSP to keep
the buffer synchronized. This process is carried out seamlessly by the DSP to assure that all compatible sample rates have their clocks
properly replaced. Compatible sample rates are 44.1 kHz, 96 kHz, 176.4 kHz, 192 kHz, and 384 kHz. Other sample rates automatically
use the recovered clock from the transport without user intervention. The 48 kHz sample rate does not support clock replacement due to
the large latency incurred by the buffer, which would cause audio from a DVD movie to be unsynchronized.
MSB POWER DAC MSRP: $3,995 plus shipping.
SELL dealer demo: $1,595 which includes USA shipping
