MSB Technology The Reference DAC User Manual page 6

About the 4 input module slots
The DAC has four input module slots. They are labeled A through D.
There are two classes of input modules, analog and digital. Analog
modules must be placed adjacent to the analog output module.
They can be either be additional analog inputs or a second analog
output module. Digital modules can be placed in any position. Each
module is completely self contained. It is recognized by the DAC
and identified on the display. When the module is not in use it is
disabled.
Available Digital Input Modules
ProI
XLR S/PDIF A single XLR digital input with a word sync output.
Optical/Coaxial
S/PDIF
MQA USB A single USB interface for playback via a computer
Renderer A renderer interface for use on a home network
Pro ISL MSB proprietary interface for use with MSB
Available Preamps
The DAC is available with one output module, but a specialized inline
XLR to RCA adaptor can be ordered.
Balanced
Preamp
Single-Ended
Adapter
S MSB's proprietary interface for use with MSB
2
transports. This module provides two inputs.
A Toslink and Coaxial digital input with a word
sync output.
based device. This module provides support for
MQA decoding. (See USB manual for operation
and setup details)
or server. (See Renderer manual for operation
and setup details)
transports. This module provides one input.
Offers one set of balanced analog inputs and outputs.
Provides volume control with our passive constant
impedance volume control technology.
For Single-Ended operation of the product, it is
necessary to buy the XLR to RCA adapters. These
adapters allow for the highest level of quality to be
achieved for your DAC by moving the conversion
components as far from the crucial and sensitive
preamp components of your Preamp module.