MAS3 Multi-channel 5.1 Audio Switcher
When
DVD-Audio and multi-channel SACDs were first introduced, a problem emerged
for those of us who needed to switch between the two different audio players.
Most A/V receivers and preamplifiers only have one 5.1 analog input interface.
This becomes an issue when several 5.1 sources exist in a system. My current
audio switcher is a homemade product that uses three DPDT (double-pole
double-throw) latching relays to switch two 5.1 sources to a single 5.1
output. While this works fairly well, there are limitations such as the
inability to control the switcher using a remote. A company called Zektor
has introduced a great new product that is designed to switch up to three
5.1 sources to the single 5.1 output to drive a receiver or preamplifier.
The user can easily switch between MAS3 inputs using the front panel buttons,
each of which has an indicator light showing the active source. In addition,
the user can program the MAS3 to automatically select an input based on
an IR remote command from their remote control. We found this feature
to be one of the best aspects of the MAS3. The front indicator lights
on the MAS3 automatically dim soon after the user changes a setting making
the unit less noticeable in a dimly lit home theater environment. Optional
rack mount ears are also available from Zektor for those who need to place
the unit in a 19" rack.
The
rear panel of the MAS3 is simply arranged with three sets of 5.1 inputs
on the left, and a single set of 5.1 outputs on the right. All of the
RCA connectors are gold plated for long-term reliability and low contact
resistance. Also shown in the picture is the optional RS232 interface
board available from Zektor, which allows users to control the audio switcher
using serial commands. The Setup
button on the rear places the MAS3 in a programming mode so that the user
can program IR commands into the switcher from their remote. Practically
any universal remote with its existing library of codes can be used to
control the MAS3. However, the MAS3 also has a learning capability to
respond to new IR remote commands read by the unit. This flexibility is
invaluable for today's systems that already have too many remotes. The
MAS3 is powered with a 9VDC AC adapter provided with the unit.
Design
The MAS3 is a passive audio switcher that uses no active electronics in
the signal path. A total of nine DPDT relays (3 per 5.1 input) are used
to control the path of the audio signal. This design helps reduce signal
loss, crosstalk and distortion by not altering the signal with active
components. This in conjunction with a well laid-out board design results
in superb audio performance. While building a multi-channel audio switcher
is not rocket science, designing one with the features of the MAS3 requires
ingenuity.
The MAS3 does have active electronics, but only for controlling the relays and communicating with the IR devices. The design is built around an Atmel AVR 8-bit RISC-based microcontroller. This small, yet powerful processor allows the unit to have capabilities far beyond the typical switcher. Nonvolatile memory within the processor stores information received via the remote. The processor also provides a simple way to interface the optional RS232 card into the system.
Performance
We connected three 5.1 audio sources to our MAS3 review unit. They included
our Sony DVP-NS900V multi-channel SACD player, Kenwood DV-5900M 5.1 DVD-Audio
player, and our Sony Vaio HTPC (Home Theater PC) installed with an M-Audio
Revolution 7.1 audio card (configured for 5.1 audio). The MAS3 greatly
simplified our setup and made it easy to listen to any of the 5.1 sources
in our system. Ultralink Platinum Series cables were used throughout the
audio chain. We listened to several different discs that we are familiar
with and the sound quality was completely transparent. We could not hear
any significant differences between a direct connection to the AVC-2500u
and routing through the MAS3 switcher. This is great news for those who
are concerned about audio degradation through a switcher such as this.
Conclusion
While the MAS3 is not a cheap unit ($449) for something that just switches
audio signals, it does offer some important features audiophiles and home
theater enthusiasts appreciate. Having full control of 5.1 source material
using a remote or the optional RS232 board is not easy to find. The question
is how important is this transparent sounding, full featured, 3-to-1 audio
switcher to you? For our setup, we certainly benefited from the features
and performance the MAS3 had to offer. Some may decide to just buy an
all-in-one DVD/SACD player, but for those who need a separate unit (such
as our setup), the MAS3 is the answer.
- Kevin Nakano
