Specifications
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Word Sync Upgrade
The DAC IV has a word sync option. First, a little bit about it. Word-sync is
typically a master clock (in studios it’s known as the house clock) used in a
system to keep everything synchronous. For playback systems, this isn’t all that
important thus it’s very rare for someone to use in a home system. However it is
important in studios as the output of the ADC convert needs to be synchronous
to the digital inputs of the rest of the devices, such as computers. If it is not, they
will have buffer overrun/underrun errors and data corruption.
When word-sync is used, they will run a standard digital signal (most common
AES/EBU, but it could also be coaxial, etc…) along with a separate cable
(typically BNC) that is the clock in word-sync format. Devices with a word-sync
input look at both the data and the clock and run the entire device off the recovered
word-sync clock. If a word-sync master clock is used, the entire system must run
off of it. The word-sync clock is sample-rate dependent.
The DAC IV has the option of word-sync. We strongly recommend people not
using it. Even if the word-sync clock source was perfect with 0 jitter, the act
of converting it to the word-sync frequency, transmitting it, recovering it, and
generating the correct frequency has 100 times the jitter of the standard clocks
in our DAC. In order to use the word-sync option in our DAC, you must have
the word-sync option that goes in the Aux 1 or Aux 2 slot.
One tricky thing we did is we tied the word-sync option to a specic input. In
most cases when word sync is present, it will be there for one source to the DAC
but the rest of the sources won’t be running off the house clock. In the menu, you will nd the option “Word Sync.” When you enter this
menu option, you will nd a list of input names (coaxial, toslink, balanced, BNC). These are the inputs that can be used with the word
sync source. Only one input can be used with the word-sync option.
For example, let’s say you have a transport with a word-sync input and you connect it to the DAC via the Balanced Digital input. You
will need to connect both the transport and the DAC with the same word-sync signal (unless the transport is the word-sync source).
Once this is done, you will go into the DAC menu and under word sync, select balanced. When the DAC switches to the balanced input,
it will automatically enable the word-sync input. When you switch away from the balanced, it will turn the word-sync off. You can tell
word-sync is working on the DAC as it will display “word sync” on the display when enabled.
Even though a server might have an excellent clock, it’s getting that clock from the server to the DAC without adding jitter that’s the
problem. It would sound better to have the DAC do it’s reclocking with the local clocks instead of running off a recovered word-sync
clock from another box run over a cable.
PRO input Upgrade
This exciting upgrade adds one or two additional MSB inputs in the AUX IN positions of the DAC IV. It is a exible board so please be
careful to check the instructions carefully when installing. First of all, make sure your rmware has been upgraded to the latest level.
Check the MSB web site for details. The upgrade offers two possible inputs:
Input #1 - Ground Isolated MSB Network
This is an improved version of the classic MSB Network. It will work with all existing MSB Network outputs on all current and older
products. This input is designed specially as the best possible input for the MSB Universal Media Transport. It has the performance of
the stock MSB Network without the coupling of ground noise. With this input both our transports can have optimal
inputs. It will work with the following:
• Data CD IV
• Universal Media Transport
• all older MSB products