Genelec 1238DF Operating Manual
Introduction
Congratulations and thank you for
choosing Genelec!
Since 1978, Genelec has been guided
by a single idea – to make perfect
active monitors that deliver neutral and
accurate sound in every kind of acoustical
environment. In Genelec’s quest for this
ultimate goal, our unrivalled commitment
to research and development has led us
to continuously develop innovative driver
technology, electronic circuitry, enclosure
designs and more.
Our design philosophy is based on
sustainability and environmental values,
where industrial design serves our
products' acoustical performance. Your
Genelec product has been designed and
manufactured with care in our factory, in
Finland, using environmentally efficient
solutions to give you reliable operation
over many years.
Please take the time to read this manual.
Happy monitoring!
General Description
The Genelec 1238DF is a three-way
monitoring system for medium sized
control rooms. It performs well as free-
standing monitor as well as flush-mounted
in control room walls. The 1238DF is fully
compatible with Genelec Loudspeaker
Manager GLM™ and the proprietary
Genelec loudspeaker control network and
Genelec SAM Series DSP Subwoofers. It
is suited for recording, film and video post-
production, broadcast monitoring as well
as for mastering.
The unique Directivity Control
Waveguide™ (DCW™) technology by
Genelec provides excellent stereo imaging
and neutral frequency response even in
difficult acoustics.
With program material at a 2 meter
listening distance, the fast low distortion
amplifiers drive a stereo system to peak
sound levels in excess of 124 dB SPL.
Drivers and Cabinet
Construction
The 1238DF reproduces low frequencies
with dual 210 mm (8 in) woofers. The
proprietary 130 mm (5 in) direct radiating
midrange driver, and a 25 mm (1 in) metal
dome tweeter are acoustically loaded by the
proprietary Directivity Control Waveguide.
All drivers are magnetically shielded.
Amplifiers and Signal
Processing
The 1238DF uses the RAM-L amplifier unit.
The RAM-L is designed to be mounted in
a 19 inch rack. Digital signal processing in
the RAM-L amplifier unit is done with high
precision algorithms, and includes driver
and amplifier overload protection. The room
response compensations include highly
flexible parametric filters, level alignment,
and acoustic delay compensation. These
allow accurate matching to all console
output sections and room acoustics.
Operating Environment
These monitors and their RAM-L amplifiers
are designed for indoor use only. The
permissible ambient temperature is 15-35
degrees Celsius (50-95°F) and permissible
relative humidity between 20% and 80%.
Humidity condensation on the product is
not allowed during use. For instance, if the
product has been stored or transported in
a cool environment and then taken into a
warm room, it must be allowed to warm
up to the ambient temperature before
connecting to mains power.
Mounting Considerations
Place the monitor so that its acoustic axis
is aimed towards the listening position
(see Figures 1 and 2). Place monitors
with left-right symmetry and at an equal
distance from the listening position.
Acoustic reflections from objects close
to monitors and the listening position
can cause colouration and blurring of the
sound image. Symmetrical positioning of
reflective objects maintains good stereo
imaging. When soffit (flush) mounting, the
wall surface should extend to the monitor,
forming a continuous surface.
Minimum Clearances
The ambient temperature around the
amplifier must not exceed 35 degrees
Celsius (95°F).
When the RAM-L amplifier is mounted
in a 19 in rack, the minimum free space is
1/2 U both above and below the amplifier
and both sides of the amplifier fully open
to enable free movement of air. Use the
included rack mount front plate to ensure
sufficient space above and below the
amplifier.
When the RAM-L is mounted on a table,
shelf or similar solid surface, there must
be a free space of at least 250 mm (10 in)
above and 10 cm (4 in) on both sides of the
amplifier. Free air flow must be possible in
the front side of the amplifier.
Description Of Connectors
“MAINS INPUT” Connector
Connect to the mains supply. The RAM-L
amplifier accepts any AC 50/60 Hz mains
voltage between 100 and 230 Volts.
“DIGITAL IN AES/EBU” Connector
The monitor defaults to reproducing an
analog input signal. The digital audio AES/
EBU input is selected automatically when
a valid digital audio signal is presented.
Use GLM software to define the AES/EBU
subframe to monitor.
“DIGITAL THRU AES/EBU” Connector
This output carries an unaltered copy of
the digital audio signal and can be used
for daisy-chaining the signal up to three
additional SAM monitors or subwoofers.
“ANALOG IN” Connector
The maximum input level of the analog
input is +25.0 dBu. The analog input must
not be overloaded, otherwise distortion
will result. When the maximum input is
exceeded, the enclosure front panel light
turns red, indicating the overload.
The sensitivity of the monitor system is
set using the GLM software. Coming from
the factory, the analog input is set to the
highest sensitivity, resulting in a sound
output of 100 dB SPL for a -6 dBu analog
input signal.
“CONTROL NETWORK” Connectors
The RJ45 sockets connect the monitor
to the proprietary Genelec Loudspeaker
