Product Review (August 2007) - Zektor
MAS7.1 HDMI/Audio Switch

By Kevin Nakano

Zektor has introduced their latest A/V switcher that includes advanced switching control for HDMI, digital audio and analog audio. The MAS7.1 features fully active HDMI and digital audio switching along with passive analog audio switching for up to 8 channels. This is ideal for the new high resolution 7.1 formats currently available. Displays often only have a single HDMI input and many audio components only offer a single set of multi-channel audio inputs. The MAS7.1 solves these problems by providing a way to use multiple sources on a single set of inputs.

Front Panel
The front panel has a set of three primary buttons and a set of three secondary buttons. There is also a Sync button that will link the primary and secondary buttons together so that if button "2" is pressed, "S2" will also be switched. The MAS7.1 is completely configurable to allow separate primary and secondary switching groups. The user can configure the input types to a specific group for maximum flexibility. All front panel buttons can also be disabled to prevent small children from changing the settings. Best of all, there are four ways to control the unit. The manual front panel controls, the IR remote, the hardwired IR input jack, or the RS-232 interface.

The MAS7.1 HDMI 1.3 interface supports resolutions up to 1080p and Deep Color up to 1080i. Analog audio interfaces have excellent bandwidth characteristics with no distortions due to active components in the signal chain. All analog audio passes through low impedance, gold-plated relay contacts to preserve signal integrity. The unit measures 17" W x 6.5" D x 1.75" H, weighs 8 pounds, and can also be rack mounted.

Rear Panel
The back of the MAS7.1 is loaded with connectors for multi-channel analog audio, digital optical toslink, coaxial digital, and HDMI. Input power comes from an external 9V, 500mA AC adapter. Any combination of optical and coaxial digital audio inputs can be used with cross-conversion between the two. A full duplex RS232 interface is provided for controlling the switcher from a controller making use of their K.I.S.S.™ (Keep It Simple Serial™) protocol. The 3.5mm (1/8") jack can be configured to receive a 12V On/Off command (3V-15V, positive or negative polarity) or an IR input signal. This input signal is completely optically-isolated from the rest of the MAS7.1 electronics to protect it and prevent noise from coupling into the unit.

Programmable Features
The MAS7.1 is unlike any other switcher we have ever used in our system. Sure it switches reliably and even has an RS232 interface on the back to command the unit from a high-end controller. However, what makes the MAS7.1 unique is the ability to adjust a variety of parameters to meet each user's taste and needs.

Indicator Lighting
The front panel lights can be adjusted to different levels. Both dim and bright levels can be set by the user using the programming mode. Once the levels are set, the user can choose to have the indicators set to dim, bright, off or smoothly transition from bright to dim 4-seconds after any adjustments are made. The latter mode is our favorite and allows the user to easily see what is being changed and then fade to a low enough level not to be distracting while watching the video in a dark setting.

Remote Programming
The MAS7.1 comes with a remote, but it is possible to use your own remote to program the controls on the unit using the Intelligent IR™ Learn Mode. Programming is very simple with only eight buttons (6 input select, sync, and power) needing assignments. This features also allows users to have multiple MAS7.1 units with fully independent control of each.

There is also a way to program discrete remote commands into the unit for Power On, Power Off, Sequence Primary, Sequence Secondary, Sync On, Sync Off, and Breakaway Video. These codes are learned in this sequential order when set into the Discrete IR Code programming mode. These commands are powerful when using a controller that is used to configure an A/V system. Rather than toggling Power or Sync, the discrete commands place the unit in a known state.

Initial Power On State
There are times when the unit may receive interrupted power due to the setup in which it is used. The MAS7.1 has a programmable power-on state that places the unit in a known configuration when power is applied. The user can select the state and then program it into the unit so that next time power is interrupted it will return to this configuration. This can be a handy feature for some installations.

Switching Delay
The switching delay time can be adjusted for each set of inputs. They are grouped as HDMI delay, Digital Audio mute delay, Multi-channel Audio delay, and Stereo audio delay. Settings can vary between zero seconds to 500ms in increments of 0 sec, 20ms, 50ms, 100ms, 200ms, or 500ms.

Primary/Secondary Mapping
Each set of inputs (HDMI, Digital Coaxial and Optical Audio, Multi-channel Audio, and Stereo Audio) can be assigned to the Primary or Secondary groups. Once the groups are defined they can be controlled independently or together using the Sync button.

We linked the HDMI and digital audio into Primary group while the 7.1 analog audio was assigned to the secondary bank. However, any combination can be used based on the need of the user. We had three HDMI sources running to the MAS7.1 that included a Dish Network ViP622 HD receiver, Toshiba HD-A1 HD-DVD player, and an OPPO Digital OPDV971H DVD player. All three components also had their corresponding optical digital interfaces going through the switcher as well. A variety of Atlona HDMI cables were used to send video to the switcher while a long 20-meter Vizionware Hi-Wirez HDMI cable made the connection to our Mitsubishi HC5000 projector.

Video Switching
Switching HDMI signals is not a trivial task and requires high bandwidth components and strict board layout constraints. The MAS7.1 uses a Texas Instruments (TI) TMDS341A HDMI switching chip to handle the 3:1 HDMI switching function. The TI chip is compatible with HDMI 1.3a and supports bandwidths as high as 1.65 Gbps. Care has been taken with the board design (as seen in the picture) to time align each of the signals within an HDMI link. Trace lengths must be well matched within each pair and each pair within a given link must be close in length to time align the channels within a link. Also, they have avoided any 90 degree bends in the traces to reduce unwanted signal reflection.

Audio Switching
The audio switching is fully passive in the MAS7.1 design. Each input channel passes through low impedance gold contact relays to reach the corresponding output channel. Because of the flexibility designed into this unit, a total of 24 relays are used to connect the audio sources to the outputs. The switching and delay times are handled by the onboard processor.

The brains of the MAS7.1 HDMI/Audio switcher lies with an Atmel high performance, low power AVR® 8-Bit Microcontroller. This processor provides basic control for the MAS7.1 and has an integrated serial port for the RS232 interface. This cost effective controller give products such as this versatility and a rich set of features at a low cost. This also allows users to store configurations in nonvolatile memory.

The MAS7.1 switching includes a full size remote with the unit. Unlike so many of the video switchers we have reviewed, the MAS7.1 remote is simple to use and not easily misplaced. Zektor decided to create a single remote for multiple applications. Only the second set of buttons are used with the MAS7.1 unit. However, should the user decide to include more Zektor components into their A/V system, the same remote can be used to control all of these products. All of the buttons found on the front panel of the MAS7.1 are also available on the remote. Unfortunately, the remote offers no backlighting for use in dark or poorly lit areas. The remote is powered from a single CR2025 3V battery.

The MAS7.1 worked well for us from the very beginning and we immediately began programming our preferences into the unit. Since we typically have a dark room for watching movies, it was important to be able to dim the front panel display when no activity was in process. We set the MAS7.1 to fade from bright to dim and having the ability to control these levels was a great feature. Some users may prefer to turn the front panel display completely off, which is also an option.

Switching between high definition (Dish ViP622 and HD-DVD) and standard definition (OPPO DVD player) sources was made simple with the MAS7.1 unit and we saw no degradation in the video. The digital audio from these sources was also switched in parallel and worked flawlessly.

We had our 5.1 analog sources from our Sony DVP-NS900V SACD player and Kenwood Sovereign DV-5900M DVD-Audio player assigned to the secondary group. This allowed us to independently switch the video/digital audio and the multi-channel analog music. We played a variety of music including DTS 5.1, SACD 5.1 and DVD-Audio 5.1. In all cases the audio was very transparent with this switcher in the signal path with no noticeable coloration or noise.

The MAS7.1 is more than a simple A/V switcher and can be a great addition to a complex A/V system. Knowing the features of this switcher is important in order to take full advantage of the options available. Programming is simple and the manual provides a clear and concise explanation of the settings. Some experimentation may be needed to fully experience the capabilities of the MAS7.1. Like other Zektor products we have seen, build quality is excellent and complements the attractive design of the unit, which is available in a silver or black finish. We plan to add the RS-232 interface control in the near future to provide direct control of the unit without the need for the IR interface. At $599, the MAS7.1 is a serious component in your system and you will be hard pressed to find anything like it. Best of all, installers will finally have a simple switching solution that can be configured to meet their customer's needs.

- Kevin Nakano

OPPO BDP-103 Blu-ray Player

Review System

Projector: Mitsubishi HC5000 Full 1080p High-Definition LCD Projector
Screen: Stewart Filmscreen 100" FireHawk Screen on a Luxus Deluxe ScreenWall
Video Processor/Scaler: Anchor Bay Technologies DVDO iScan HD+ A/V Processor
Preamplifier/Processor: Parasound AVC-2500U THX-Ultra DTS/DD Preamp/Processor
Amplification: Parasound HCA-2205AT THX-Ultra Five Channel Amplifier
Bass Management: Miller & Kreisel BMC Mini 5.1 Bass Management Controller
Front Speakers: Miller & Kreisel S-150THX (L+R) and S-150AC (Center) Speakers
Rear Speakers: Miller & Kreisel SS-250 Tripole® Surround Speakers
Subwoofer: Two Miller & Kreisel MX-350THX MkII THX-Ultra Push-pull Subwoofers
Room Treatments: Echo Buster panels and Bass Buster towers
Set-top Box: Dish Network ViP622 HDTV Satellite and Terrestrial Receiver with HDMI
HD-DVD Player: Toshiba HD-A1 HD-DVD Player with HDMI
DVD/CD/SACD Player: Sony DVP-NS900V DVD/CD/SACD Player
DVD Audio/Video Player: Kenwood Sovereign DV-5900M 400-Disc DVD Changer
DVD Player: OPPO Digital OPDV971H DVD Player with DVI Output
D-VHS VCR: JVC HM-DH30000U D-VHS High-Definition D-Theater VCR
Media Server: Kenwood Sovereign MRH1 Entre
Remote Control: Remote Technologies Inc. T3 Controller
HDMI Video Switcher: Radiient Technologies Select-4 HDMI Video Switcher
HDMI Cable: VizionWare Hi-Wirez 15-meter Active 1080p Cable
HDMI Cable: Accell UltraRun 45-meter 1080p Cable
DVI Cable: AudioQuest DV-1 20m DVI-D Cable
A/V Cables: Ultralink Platinum and Advanced Performance Series Cables

Review - At a Glance

Zektor - MAS7.1 HDMI/Audio Switch


Three 7.1 Channel Audio Inputs and One Output
All channels are passively switched with no active electronics used to route audio signals.

HDMI 1.3a Compatible Switch
A 3x1 HDMI switch allows full switching between a HD-DVD and a Blu-ray player and and still have an extra input for a PS3 playstation or Home Theater PC.

Digital Audio Switching
S/PDIF compliant Optical and Coax audio switching is also supported with auto conversion being done between the two digital formats.

Passive Switching of Analog Signals
By using relays to route audio signals, as opposed to active analog switching ICs, we are able to achieve the same quality of signal pass through, that would be achieved by manually swapping 6 cables each time you switched between HD-DVD, Blu-ray, SACD and DVD-A players. There's no reason to compromise signal integrity for the convenience of having a remote controlled audio switch.

The MAS7.1 was designed with audio in mind, however the passive analog switching used in the MAS7.1 is that same as that used in our passive video switches. Each of the eight analog channels feature a 0Hz-200MHz +0/-3dB frequency response and can be used to switch 1080p component video as well as audio signals.

Extremely Configurable
The MAS7.1 can be configured as two independent switches. The 7.1 audio channels can be split to create a 5.1 channel switch, and a stereo audio switch, allowing the L/R stereo signals to be switched independent of the 5.1 channel audio. The digital audio and HDMI switches, can be configured to follow the 5.1 audio or stereo audio switch, or any combination of the above.

Gold Plated Connections
Gold plated RCA connectors are used throughout the design to reduce the possibility of contact generated noise caused by corrosion.

Features Zektor's Exclusive IIR Learning
The MAS7.1 comes with it's own remote control. However if more than one MAS7.1 is used in one room, the MAS7.1 features Zektor's exclusive IIR (Intelligent Infra-Red) learning. Zektor's IIR™ learning allows the MAS7.1 to work with virtually any remote control! All discrete codes are supported as well.

Opto-isolated Hardwired IR Jack
Hardwired IR control has always been tricky. There are no voltage standards and no polarity standards. Does the IR connection share a common ground with video or audio connections? Should the IR signal be modulated, or unmodulated / demodulated? In an effort to achieve the near impossible goal of "Just plug in your IR controller and it will work!" we've done everything we could think of to answer all the above questions with "It doesn't matter, it'll work!".

We started by opto-isolating the input jack. So grounding is no longer an issue, either side of the signal can be grounded, and neither side of the signal need be grounded. We accept a wide range of voltages, from 3 to 15 volts, which can be positive or negative. If your controller sends unmodulated signals, then we'll use them as is. If your controller modulates the signals, no problem, we demodulate them, and use the results. All done automatically.

Your time should be spent configuring your system, not configuring your system to work with us.

Built-in RS-232
For compatibility with Crestron or AMX type setups, an RS-232 port included with the MAS7.1. The bi–directional RS-232 protocol allows for full control and inquiry of the current MAS7.1 state.

Auto Dimming Display
The LED indicator lights can be set to Bright, Dim, or an Auto Dim mode. The Auto Dim mode will fade the LEDs to half power about 4 seconds after a channel is selected. The bright and dim levels are user adjustable from very bright, to off.

Rack Mountable Metal Enclosure (1RU)
Enclosed in a steel chassis with a machined, brushed aluminum front panel, and available in black or silver, the MAS7.1 seamlessly integrates into your existing home theater environment.

Optional International Power Supply
Available with an international power supply for 90-264VAC, 47-63Hz operation. The international supply comes with adapters for UK, EURO, AUS and USA use.

Analog Channels
Signal To Noise:
Dynamic Range:
Audio Frequency Response:
Video Frequency Response:
Insertion loss:
Adjacent Channel Crosstalk:
Unselect Channel Crosstalk:

Digital Video

DVI / HDMI Bandwidth:
DVI / HDMI Pixel Clock:
HDTV Resolutions:

HDMI Audio:

PC Resolutions:

Digital Audio

Transfer Rates:
Digital Audio Modes:
Coax Input Levels:
Coax Output Level:

IR Sensor:
IR Jack:
+12V Control:
Serial Port:

Power Requirements:
Optional International:
Power Supply:


Eight @ full bandwidth (200MHz)
0dB (Passive)
90dB re +4dBu, 22KHz BW
112db re +26dBu, 22KHz BW
0Hz-100KHz, +0/-.05 dB
0Hz-200MHz, +0/-3dB
Less than 0.05db, 0Hz-100KHz
Less than -100db, 0Hz-100KHz
Less than -100db, 0Hz-100KHz

All DVI 1.0 and HDMI 1.3a modes
All resolutions, audio modes,
and deep color modes

2.25 Gbps
225 MHz
480i thru 1080p
including 480p, 720p and 1080i

All DVI and HDMI HDCP modes
Supports all HDMI Audio modes

640x480 through 1920x1200
(All single link PC resolutions)

3 Coax, 3 Optical (auto-converting)
1 Coax, 1 Optical (simultaneous)
Optical: 13.2Mb/S, Coax: 50Mb/S
PCM,DD5.1,DTS,All Audio Modes
200mV - 7.0V (PC card compatible)
500mV nominal into 75 ohms

Modulation Freq: 34KHz-42KHz
3V to 15V (any polarity, mod/unmod)
3V to 15V for ON, < 0.2V for OFF
9600 (8N1), K.I.S.S.™ Protocol
USB Cable Compatible
Firmware Upgradable

1W Standby, 3W On
90-264VAC, 47-63Hz, 15W
9V @ 500ma, U.L. Listed
17"W x 6.5"D x 1.75"H

Two year parts & labor


  • MAS7.1 unit
  • 9VDC AC Adapter
  • User Manual
  • Download User Manual

    Company Information
    12675 Danielson Ct., Suite 401
    Poway, CA 92064
    Phone: (858)748-8250

    Post Sales:

    Source: Manufacture supplied
    Model Number: MAS7.1
    MSRP: $599

    Warranty: 2 years parts and labor


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