Product Review (March 2004) - Zektor
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.

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.

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.

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

Review System

Projector: Epson PowerLite™ LCD Home Theater Projector
Da-Lite 92" Cinema Contour Frame with High Contrast Cinema Vision Screen
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 TripoleŽ 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: Mitsubishi HD-5000 Receiver
D-VHS VCR: JVC HM-DH30000U D-VHS High-Definition D-Theater VCR
DVD/CD/SACD Player: Sony DVP-NS900V DVD/CD/SACD Player
DVD Audio/Video Player: Kenwood Sovereign DV-5900M 400-Disc DVD Changer
Laserdisc Player: Pioneer CLD-D704 CD/VCD/LD Player
A/V Cables: Ultralink Platinum and Advanced Performance Series Cables
DVI Cable: Transparent Audio 30-foot HPDVI DVI-D Cable

Video Generator: Sencore VP300 SDTV/HDTV Video Pattern Generator
Video Signal Analyzer: Sencore VSA794 NTSC Video Signal Analyzer
Color Analyzer: Sencore CP5000 Multi-Display Color Analyzer

Review - At a Glance

Zektor - MAS3 Multi-channel Audio Switch


  • Passive Swiching Design uses relays for low loss, crosstalk, and distortion.
  • IR Remote Control Receiver works with existing remotes.
  • Gold plated RCA connectors for long-term reliability.
  • Auto dimming Display for optimal viewing in a dimly lit home theater.
  • Excellent build quality in a full sized enclosure with rack mount options available.

    Insertion Loss (0 - 100KHz):

    0 dB

    Adjacent Channel Crosstalk (20KHz): less than -104 dB
    Unselected Channel Crosstalk (20KHz): less than -104dB
    Power Consumption: less than 5W (1W typical)
    Size: 17"W x 6.5"D x 1.75"H


  • MAS3 unit
  • 9VDC AC Adapter
  • User Manual
  • Download Brochure

    Download User Manual

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

    Post Sales:

    Source: Manufacture supplied
    Model Number: MAS3
    MSRP: $449

    Warranty: 1 year parts and labor


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