Specifications
3
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 ltered 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 lter, and improves the sound. As you can see, upsampling the
input signal to a higher frequency reduces the ltering requirements and thus improves the sound. This is the current state-of-the-art as
exemplied 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 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 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 ltering 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 ampliers have slew rates greater than 2500
Volts/microsecond. The output impedance of the Power DAC is 50 ohms.
Special Features
The Power DAC has many special features. The following sections discuss these features and how they work.
Upsampling and filtering
As MSB technology has developed, so has our DAC architecture. Our advanced digital lter now replaces the asynchronous upsampling
of earlier models. The 16X Digital lter 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 lter response permits the user to choose the lter design they prefer. It allows for the selection of a standard
brick-wall lter or a slow roll-off lter, both at half the sampling frequency. Each provide a distinct, glorious listening experience. You
may favor one or the other, or enjoy changing the lter response to suit the music you listen to. Music with less high frequencies may
benet from the slow roll-off lter.
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 DAC has a custom DSP based Digital lter 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 DF1704, which at the time was the best Digital Filter on the market.
Our Digital Filter is built to our specications 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 lter also dramatically increases the resolution
and dynamics of the machine. This lter is also completely customizable; By playing a special .wav
le on a CD new lter coefcients, either temporary or permanent, can be loaded into our DSP.
The Digital Filter is a 16x oversampling, single stage lter with 32 bit input resolution, 80 bit compu-
tation, and 36 bit coefcients.
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 DAC does no such re-clocking. We actually pay no at-
tention 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 high-
speed 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 lter.
Sign waVe (0 db, 19.95 khz teSt
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