Product Review (February 2008) - Oppo
HM-31 3:1 HDMI 1.3 Compliant Switch

By Kevin Nakano

Oppo Digital, Inc. located in Mountain View, CA has a reputation for producing high value products that offer consumers excellent performance for the dollar. Therefore, it is not surpring to see that their latest HDMI 1.3 compliant switcher is available for only $99. The OPPO HM-31 is a 3-to-1 HDMI switcher that features some of the latest chip technology from Silicon Image (one of the founders of HDMI). The HM-31 uses a VastLane™ SiI9185 HDMI Switching chip and is one of the very few HDMI switches to pass the official HDMI 1.3 certification test. This certification ensures that the HM-31 HDMI Switch is compatible with all HDTV resolutions up to 1080p with Deep Color and PC resolutions up to 1920x1200. The switch is EIA/CEA-861D, DVI 1.0, and HDCP 1.1 compliant and supports DDC and HPD switching to ensure maximum device compatibility. The HM-31 also includes other high-end features such as an RS-232C and IR interface and built-in signal equalizer for longer cable lengths.

The OPPO HM-31 comes with a universal AC power adapter (100-240VAC, 50/60Hz) that supplies 5VDC at 1 amp to the unit. Also included is a small IR remote for selecting one of the three HDMI inputs. The front panel of the HM-31 has indicators for each of the three HDMI inputs. A power indicator is on the front and top of the unit near the power input jack. A manual input select button is available when the user wants to change the input channel by simply pressing the button.

Rear Panel
The rear panel of the HM-31 has four HDMI connectors (3 in and 1 out), an RS232C connector, IR extender input, and a power input jack. Our test cable included a 45-meter Accell UltraRun. We sent high speed data over this long cable to our projector with success. It is not easy to transmit data over this distance, yet the HM-31 easily handled 1080p movies running at 24 frames per second.

True 1080p/60 Bandwidth
Next we bumped up the data rate through the HM-31 by loading NBA07 on the PlayStation3, which outputs 1080p video at a full 60 frames per second. We used our Mitsubishi HC5000 projector to display the input video information on the screen. We connected the PlayStation3 through the HM-31 HDMI switch to show the real video data rate. We are still amazed that such an inexpensive product can perform so well. This is the ideal switch for products such as the PS3 that support 1080p and Deep Color.

The OPPO HM-31 Switch measures only 7-3/8" x 4-1/2" x 1-1/16" and is a lightweight design. The top of the unit is a black anodized brushed aluminum surface that gives the HM-31 an elegant look. The bottom of the unit has three slotted holes that allow it to be mounted on a wall or cabinet. If this option is used, it would be wise to keep the unit close to the ground to prevent the weight of the cable from pulling out of the HDMI connectors. Unfortunately HDMI connectors do not fully lock, but do have some friction that help keep them in place.

The Oppo HM-31 not only has great performance, but it does so at an unheard price of only $99. The design is solid and leverages from the latest HDMI technology from Silicon Image. The support of both IR commands and the wired RS232 make the HM-31 a real winner. If your system requires an HDMI switch due to limited inputs on your display, then this is the unit to get. Few HDMI switches work this well and none of them can do it at this price.

- Kevin Nakano

OPPO BDP-103 Blu-ray Player

Review System

Projector: Mitsubishi HC5000 Full-HD 1080p 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
DVD/CD/SACD Player: Sony DVP-NS900V DVD/CD/SACD Player
Blu-ray Player: Sony PlayStation3 Game Console and Blu-ray Player
DVD Audio/Video Player: Kenwood Sovereign DV-5900M 400-Disc DVD Changer

D-VHS VCR: JVC HM-DH30000U D-VHS High-Definition D-Theater VCR
A/V Cables: Ultralink Platinum and Advanced Performance Series Cables
DVI Cable: AudioQuest DV-1 20m DVI-D Cable
HDMI Cable #1: VizionWare Hi-Wirez 20-meter Active HDMI Cable
HDMI Cables #2: Accell UltrRun 45-meter Active HDMI Cable
Power Conditioning: Panamax MAX 5510 ACRegenerator
Video Generator #1: Gefen 1080p HDMI Video Pattern Generator
Video Generator #2: Sencore VP300 SDTV/HDTV Video Pattern Generator
Color Analyzer #1: Sencore CP5000 ISF Certified All-Display Color Analyzer
Color Analyzer #2: ColorFacts PRO with GretagMacbeth Eye-One Pro Colorphotometer

Review - At a Glance

OPPO - HM-31 Advanced 3x1 HDMI Switch


  • Easy and convenient selection from up to three HDMI sources
  • HDMI 1.3 specification with DDC and HPD switching
  • Fully supports 1080p, Deep Color , and all HDTV resolutions
  • EIA/CEA-861D, DVI 1.0, HDCP 1.1 compliant
  • Long cable support with built-in equalizer
  • Maintains highest video and audio quality
  • Remote control
  • Custom installation options – external IR input and RS-232C port


Standard Compliance

HDMI 1.3, EIA/CEA-861D, DVI 1.0, HDCP 1.1

HDMI Output Port


HDMI Input Ports


Signal Range

Up to 1080p@60Hz or 720p/1080i@120Hz with 12-bit color depth

Remote Control

Built-in IR Sensors: 2
External IR Sensor: optional
RS-232C: optional

Power Consumption

3 Watts (max)

Power Adapter

Input: ~ 100V – 240V, 50/60Hz AC
Output: 5V DC, 1A max

Operating Temperature

5C - 35C
41F - 95F

Operating Humidity

15% - 75%
No condensation


7-3/8" x 4-1/2" x 1-1/16", 187mm x 116mm x 27mm


9oz or 0.25kg

HM-31 Data Sheet

Company Information

OPPO Digital, Inc.
2269 Old Middlefield Way
Mountain View CA 94043 USA

Phone: 650-961-1118
Source: Manufacturer Supplied
MSRP: $99


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