Meridian hdmax 421, HD MAX 121 Specifications

Placed towards the display end of the HDMI
path, the 121 Extender allows HDMI cable runs
of up to about 50 metres (150+ feet)*. This is
particularly useful when a digital video display
device such as a projector is a considerable dis­tance from the video source driving it. The unit
is typically placed near the projector or other
display device. Proprietary active termination,
automatic cable equalisation, buffering and
de-jittering technology visibly improve image
quality, reduce noise and stabilise the video
– even on short cable runs. The automatic signal
correction allows signals between –20dB and
+6dB to be restored to perfect level, edges and
eye pattern, making the Extender an ideal HDMI
or DVI problem-solver.

The 121 Extender is a small box designed to bolt
into position unobtrusively near the display unit;
it may also be positioned part-way down the
signal path. The unit has one input and one out­put: the output is connected via a short HDMI
cable to the display while the input is connected
via a long cable to the video source component.
DVI/HDMI cables can be used with DVI sources
and destinations. The 121 Extender is powered
by an external universal voltage supply or may
be operated by any DC supply from 6 to 15V at
under 2W consumption, making it suitable for
powering from a projector trigger source for
example. It can also be powered from the HDMI
cable itself in some circumstances. An indica­tor LED illuminates when lock is established; a
power indicator LED is also included.

The 421 Switch is a four input, one output
HDMI switching unit with extremely wide band­width and employing proprietary technology to
switch high-resolution digital HDMI video and
audio. Each input also includes Meridian’s HDMI
Extender technology to improve image quality
and stability and reduce noise and jitter on both
short and long cable runs.

Broadcast-quality, High­Definition HDMI/DVI
extender & four-way switch

Allows cable runs of up to 50
metres (150+ ft)

Improved image quality:
lower noise, greater stability

Automatic signal correction
4-into-1 HDMI switch box

allows simple input selection
under remote control

Carries HDMI 6-channel
24/96 & bitstream audio, and
video at up to 1080p

DVI compatible (adaptor
cables required)

121 Extender & 421 Switch

The High-Density Multimedia Interface, or HDMI, is ideal for connecting High Definition
digital video sources to digital displays such as projectors and flat panels. HDMI also allows
high-quality digital audio to be carried along the same cable.

In addition, HDMI carries digital video with definitions up to 1080p, the highest definition
currently available on display equipment and significantly in advance of the capabilities of
existing HD broadcasters (which are generally 720p or 1080i).

The latest release of the specification allows up to six channels of high-resolution 24-bit
digital audio to be carried at sampling rates up to 96 kHz, in addition to bitstream data. This
corresponds to the multichannel specification for high-resolution audio disc formats such as
DVD-Audio and DualDisc, and emerging high-density audio/video disc formats.

The HDMAX121 Extender uses active termination, automatic cable equalisation, buffering
and de-jittering to achieve extended HDMI/DVI cable runs, while the HDMAX421 Switcher
offers four-into-one HDMI switching with both local and multiple remote control capability.

HDMAX 421 Switch (top) and
121 Extender (right).
Above: rear panels showing
connections. Not to the same
scale.

DVI DISPLAY

HDMAX121

HDMAX421

MERIDIAN DVD COMPUTER W/DVI HD-VCR HD SATELLITE RECEIVER

UP TO 150ft

DVI to HDMI CABLE

HDMI to DVI CABLE

HDMI
HDMI from
Meridian player
DVI/HDMI
converter cable

The 421 Switch can be controlled in several
ways. For direct use, a front-panel button al­lows the users to step through the inputs. LEDs
indicate which input is selected.

For serial control, a 9600 baud serial port is pro­vided, allowing interfacing via RS232 command.
In addition, sources may be assigned to different
inputs, eg DVD = input 1, etc.

This allows the unit to be controlled via Meridian
Comms (DIN or BNC) so as to select the correct
input automatically when a source is selected in
a Meridian system.

Input assignment can also be carried out in the
Meridian configuration application.

Input 1 on the 421 Switcher also automatically
senses the presence of a Meridian DVD-Audio/
Video player. When the Meridian player detects
the presence of a Switcher, a range of ad­ditional options become available in the player’s
on-screen display allowing video sources to be
assigned to the other Switcher inputs instead of
going via the player’s internal format conversion
and scaling. (Player firmware revision 1.86 or
later required.)

A G12 infrared sensor may be connected via
a Comms port for infrared remote control
capabilities.

The 421 Switch includes indicators correspond­ing to each input to show which is currently

selected. The selected input indicator comes on
solidly when an HDMI input is valid, and flashes
when it is invalid.

The 421 Switch is powered by a separate univer­sal voltage supply or may be powered by any DC
supply from 6 to 15V, at under 3W. It has rubber
feet that may be removed to reveal mounting
holes for permanent installation.

Both the 121 Extender and 421 Switch pass
both HDMI audio and video and are completely
transparent to handshaking, control and data
signals, with extremely high bandwidth and
virtually zero latency.

Extender Specifications

Dimensions: 73 x 30 x 130 mm/2.85 x 1.2 x 5.1 in (WxHxD overall)
I/O: One HDMI input connector

One HDMI output connector
Power input socket (barrel type, centre positive)

Indicators: Power, lock LEDs
Power: Unit accepts DC in the range 6–15V, <2VA (W)

Common specifications

Cable lengths: 0 to 50m over 24 AWG Shielded twisted pair

0 to 36m over 28 AWG STP
0 to 30m over 30 AWG STP

Compatibility: 480i, 480p, 720p, 1080i, and 1080p DTV resolutions

Auto correction: Signals between –20dB and +6dB are restored to

perfect level, edges and eye pattern

Construction: Mild steel finished in matte black
Power supply: Universal voltage external PSU G29043 supplied.

Switcher Specifications

Dimensions: 220 x 44 x 120 mm/8.6 x 1.75 x 4.7 in (WxHxD inc feet)
I/O: Four HDMI connectors for inputs 1–4

Input 1 includes special sensing for Meridian player
One HDMI output connector
One Meridian Comms DIN connector
One Meridian Comms BNC connector
One DB9 RS232 interface (9600 bits/sec, 8N1)
Power input socket (barrel type, centre positive)

Indicators: Per-input LED indicates valid (solid)/invalid (flashing)

HDMI input selected

Controls: Front-panel button manually steps through inputs;

RS232 input selection; control via Meridian DVD-A/V
player; infrared control with G12 sensor (not sup

-

plied)

Power: Unit accepts DC in the range 6–15V, <3VA (W)

Meridian Audio Limited

Latham Road,
Huntingdon, Cambridgeshire PE29 6YE
United Kingdom
Tel [phone]
Fax [phone]

Meridian America Inc

8055 Troon Circle, Suite C
Austell, Atlanta GA 30168-7849
USA
Tel [phone]
Fax [phone]

Email: [e-mail]
Web: www.meridian-audio.com

*Information contained in this data sheet is correct as far as possible, but Meridian Audio accepts no liabil­ity for errors or omissions. E&OE. Trademarks are the property of their respective owners. Meridian Audio
reserves the right to amend product specifications at any time. ©Text & images 2005 Meridian Audio Ltd.

HDMAXDS v1.2 • 20050831 RE

121 Extender & 421 Switch

Typical application using
HDMI and HDMI/DVI
converter cables.