Genelec 8331A operation manual

8331A

Smart Active Monitor

Operating Manual

Introduction

Acoustically Concealed Woofers (ACW™)

Thank you for choosing a Genelec product! Fulfilling dreams by
offering people the most truthful sound reproduction possible
has been the source of our enthusiasm since 1978. There´s
already over one million Genelec monitors around the world ­welcome to our story!

All Genelec monitors are designed, hand assembled and
tested at our factory in Iisalmi, Finland. Our monitors are designed
to last for decades and we take care that our customers receive
excellent support and technical services throughout the life-time
of the products.

Please register your monitor at http://www.community.
genelec.com/. You will receive an extended 5 year warranty
for spare parts. For more information about our service and
technical support see

http://www.genelec.com/customer-service.

System Characteristics

Each 8331A is supplied with one mains power cable, one
5-meter GLM network cable and this operating manual.

The Genelec 8331A is suitable for professional monitoring
applications calling for very high precision and reliability.
It combines many remarkable Genelec technologies to
provide point source benefits with directivity control over an
extraordinarily wide audio bandwidth.

Genelec Loudspeaker Manager™ (GLM™)

Software And GLM User Kit

The GLM software gets the most out of 8341 and tailor-fits it to
your room. GLM is available for download free of charge at www.
genelec.com/glm. Check in from time to time to take advantage
of new features, or consider using the cloud-based version. A
GLM User Kit comprising the necessary hardware, including the
GLM Adapter and measuring microphone is needed for building
and operating the GLM network. This kit can be purchased at all
certified Genelec dealers.

Minimum Diffraction Coaxial (MDC™)

The minimum diffraction coaxial driver is comprised of a powerful
midrange driver combined with a tweeter driver extending to
ultrasonic frequencies. This unique arrangement eliminates or
minimizes acoustic diffraction sources that typically exist in
coaxial drivers and produces a flat frequency response both on
the acoustical axis and at all off-axis directions.

The 8331 may be oriented either horizontally or vertically and
is intended for near-field listening where the influences of the
room can be mostly minimized. Typical distances can vary from
1 meter or less to 3 meters depending on room size and SPL
requirements.

Directivity Control Waveguide (DCW™)

The 8331A has an unusually large directivity control waveguide
extending over the whole front face of the enclosure. The
midrange driver cone also forms a part of the directivity control
waveguide for the tweeter. From behind the waveguide, two
woofers radiate audio through two openings in the enclosure
front. This unique design enables directivity control of all audio
frequencies down to low bass.

A pair of nearly invisible woofers in the 8331A are placed
acoustically coaxially with the midrange/tweeter drivers to
create a three-way system with all drivers having their acoustical
axes in the same position. This creates an ideally working point
source radiator.

Smart Active Monitor (SAM™)

Genelec SAM technology can improve the reliability and accuracy
of monitoring. Smart Active Monitors have several parametric
notch and shelving filters that can be tuned automatically using
the Genelec Loudspeaker Manager (GLM) software to exactly
compensate for colorations generated by room acoustics. This
enables SAM monitors to sound neutral and achieve accurate
stereo imaging in all acoustical environments.

Audio Inputs

The 8331A’s audio inputs are designed to integrate easily into
all professional environments, supporting balanced line analog
and AES/EBU format digital signal. The maximum analog input
level is +25 dBu (13.7 Vrms or 19.5 V peak). Set to the maximum
sensitivity, an analog input signal of -6 dBu produces 100 dB SPL
sound level at 1 meter in free space. A -30 dBFS digital audio
input level produces 100 dB SPL level at 1 meter in free space.
Note that 0 dBFS refers to the largest possible digital input value.

The XLR audio input accepts both AES/EBU format digital
signal and analog line level analog audio signal. With an
extremely low level AES/EBU signal, the automatic selection
may not work properly. In such case, the signal selection can be
made in the GLM software.

When using a digital audio source with adjustable level, it
may instead be advantageous to lower the output level of the
8331A using the monitors on-board rear panel controls. This
enables the use of a higher source output level with more digital
resolution, while taking full advantage of 8331’s impressively
low self generated noise.

The AES/EBU format supports two channels of audio in a
single cable. The DIGITAL OUT male XLR connector carries an
unaltered copy of the digital input signal. This enables daisy­chaining of up to four monitors. The proper digital channel can
be selected using DIP switches or GLM.

Power Management

The 8331A mains power input supports any mains voltage
globally (100-240 VAC, 50-60 Hz). It can be plugged in anywhere
in the world and will always deliver the maximum output power
to the drivers even when the mains voltage fluctuates. If mains
power is provided with a generator, inverter or lower-quality UPS
device, we recommend filtering out harmonics from the mains
power voltage.

The energy saving function Intelligent Signal Sensing (ISS™)
puts the monitor automatically into a deep sleep state when no
input signal is present. The device then consumes less than
one watt of power. Upon sensing an input signal, the monitor
automatically awakens. The wait time until entering the power
saving state can be configured using the GLM software. When
ISS is active, you can leave your monitors on at all times and
have the monitoring system immediately ready for action. The
default wait time when ISS is enabled using the ISS DIP switch
is 60 minutes.

2

COMPUTER

CONNECTORS

ORS:

ANALOG IN

RUNNING
GLMSOFTWARE

MICROPHONE

PLACED IN

THE LISTENING

POSITION

GLM ADAPTER

USB CABLE

SUBWOOFER

GLM

MONITORS

TERMINATOR

292-0063

GLM NETWORK
CABLE

Figure 1. GLM control network cabling

A

ISS

GLM

NETWORK

DIGITAL

B

100dBSPL(1 m)

-10dB

-20dB
STORED

LEVEL

INPUTdBu

PRODUCING

RESETTO FACTORY

SETTINGS:PUSH

BUTTONFOR10SEC

DIGITAL THRU

AES/EBU

8331A

COAXIALTRI-AMPLIFIED

SMARTACTIVEMONITOR

ROTARY LEVEL
CONTROL

-4

-6

-2

0

dBu

+6

POWER
SWITCH

AUDIO SIGNAL

+2

+4

DIGITALIN

AES/EBU

ANALOGIN

CONNECT

292-8331T-6

-DIGITAL THRU

-DIGITAL /

DIP SWITCHES FOR

STAND-ALONE USE

ON
OFF

-4-2-4

-2

+2

(dB)

(dB)

BASSTILT

DESKTOP160Hz -4

BASSROLL-OFF

MAINS

INPUT

MAINSINPUT

50/60Hz60W

100-240V~

MADEIN FINLAND

SERIALNUMBER

Thisdevice complieswith FCCPart 15andCanadian
ICES-003radio frequencyClassBemissionrequirements.
Referto operatingmanual forfullinformation.

GLM NETWORK

-4

TREBLETILT

www.genelec.com

LEDDISABLE

Figure 2. Connectors and controls on the back panel of a 8331A.

Setup Using The

GLM™ Control Network

Although the 8331A can be used without the GLM software and
control network, it can only reach its full potential when set up
and calibrated using GLM software, running on a Mac or PC.

Genelec therefore recommends setting up the 8331A
and other SAM monitors using GLM. You can find a detailed
description of the setup and the use in the GLM System
Operating Manual.

The GLM software and the proprietary Genelec monitor
control network offer automated acoustic equalization and

Figure 3. Connector panel detail.

alignment for any reproduction system from mono over stereo
to complex 3D immersive audio setups, including also one or
more subwoofers. GLM includes AutoCal, an expert algorithm
built on data from thousands of professional listening rooms.

Setup with the GLM User Kit consists of the following steps:

1. Connect a CAT5 (RJ45) cable between each monitor (and
subwoofer) and finally to the control network input of the
GLM Adapter device (see Figure 1).

2. Connect the GLM Adapter to computer USB connector.

3. Using a microphone stand, place the Genelec measurement
microphone at the listening location with the microphone
pointing upwards and the microphone top at the height of
the engineer’s ear. The microphone is a part of the GLM
User Kit.

4. Connect the microphone cable to the microphone input in
the GLM Adapter device.

5. Download the GLM software at the Genelec web site (www.

3

h1

ACOUSTIC

h2

ACOUSTIC
AXIS

AXIS

h1 = 163 mm (6 3/8 in)
h2 = 116 mm (4 9/16 in)

Figure 4. The location of the acoustic axis.

genelec.com). Install the GLM software and follow the
instructions in the software to measure and set up your
monitors.

6. If you plan to not use a computer for controlling the
monitors, use the GLM software to write the settings into
the monitors (use menu item “Store | Store the Current
Group Settings…”).

The GLM network may also be used for monitor control ­switching between sets of loudspeakers, solo, mute, invoking
calibrated levels etc. - or settings can be permanently stored in
all monitors for a static and predictable setup. If so, a computer
is only needed for the setup.

If the network is disconnected, settings stored using the GLM

software can be enabled by setting the DIP switch “Stored” to ON.

The CONTROL NETWORK RJ-45 connectors are used for

the GLM network. These connectors are not Ethernet LAN
compatible. Do not connect to an Ethernet LAN.

Setup Without Using The GLM

When GLM is not available, you can still adjust the 8331A for
placement in a room by using the DIP switches on the back of the
monitor. Settings are more limited but nevertheless provide the
fundamental equalizers to compensate for the acoustical effects
of the listening room, input selections and input sensitivity. To use
this method, ensure that the GLM management network is not
connected and set the DIP switch “Stored” to its OFF position.

Figure 5. Symmetrical layout and keeping the acoustic axis clear
from obstructions minimizes reflection surfaces and maintains
accurate localisation because reflections are symmetrical.

Monitor
Mounting Position

Flat anechoic
response

Free standing in
a damped room

Free standing in
a reverberant room

Near field on
a reflective surface

In a corner None -4 dB -4 dB None

Table 1. Suggested Tone Control settings for some typical monitor
placement positions.

Treble

Tilt

None None None None

None -2 dB None None

None -4 dB None None

None -2 dB None -4 dB

Bass

Tilt

Bass

Roll-Off

Desktop

Bass Tilt Control

The Bass Tilt control switches offer three attenuation levels for
the bass response below 800 Hz. The attenuation levels are -2
dB, -4 dB and -6 dB (both switches ON). This control is usually
necessary when the monitors are placed near room boundaries
such as at the wall or close to a room corner.

Stand-Alone Control Functions

Bass Roll-Off Control

The Bass Roll-Off control attenuates the monitor’s output near
the cut-off frequency. Attenuation levels of -2 dB, -4 dB or -6 dB
(both switches ON) can be selected by combining settings on
one or more switches. This setting may be needed to control the
bass level in spaces with strong low frequency reverberance.

Desktop Reflection Compensation

The desktop low frequency control attenuates the bass
frequencies around 160 Hz by 4 dB. This feature is designed to
compensate for the boost occurring often when the monitor is
placed upon a meter bridge, table or similar reflective surface.

4

Treble Tilt Control

The Treble Tilt control allows adjusting the high frequency
response above 5 kHz by +2 dB, -2 dB or -4 dB, which can
be used for correcting an excessively bright or dull sounding
system or to compensate for the high frequency level loss when
the monitor is placed behind a screen.

LED Disable

This switch shuts off the front panel LED light.

ISS

This switch activates or deactivates the ISS automatic power
saving function. The default time for ISS activation is 60 minutes,
but the time can be adjusted in the GLM software.

Colour Indication

Solid greed Normal state, normal operation

Blinking green GLM is adjusting the monitor

Green blink every 10 sec. Monitor is in an ISS power saving sleep

state

Red blink Power amplier overload protection is

active (audio is modied because of
protection)

Solid red Monitor is muted

Yellow Monitor is not in the active (playing)

group

Yellow blinking Overheat protection is active (audio is

modied because of protection)

Table 2. Monitor front panel light indications summary

Digital

The Digital switch selects the digital audio channels on the
AES/EBU. Turning both switches on reproduces the sum of the
A and B channels. When both channels are selected 6 dB of
attenuation is applied to avoid overloading the monitor.

Level

The Level switches reduce the monitor output in 10 dB steps
(-10 dB, -20 dB and with both switches set to ON, -30 dB). The
effects of these switches combine with the effect of the rotary
level adjustment control. The total setting range is 42 dB.

Stored

The Stored switch selects between the application of the
above listed controls on the monitor’s back panel and applying
the settings stored inside the monitor memory using the GLM
calibration software. Setting the Stored switch to the OFF
position selects the settings defined by the monitor’s controls.
Setting the Stored switch to ON position selects the use of
internally stored GLM settings. When the Stored switch is set
to the ON position the adjustments on the monitor have no
effect.

Operating Environment

This product is designed for indoor use only. The permissible
ambient temperature is 15-35 degrees Celsius (50-95°F) and
relative humidity 20% to 80% (non-condensing). To prevent
condensation of humidity, after the product has been stored
or transported in a cool environment and is then taken into a
warm room, wait 0.5-1 hours before opening the packaging and
connecting to the mains power.

Sufficient cooling around the 8331A must be ensured. The
minimum clearance behind, above and on both sides of the
monitor is 50 mm (2 in). If the product is installed in a recess,
the space must be ventilated sufficiently to dissipate the heat.

Mounting And Placing Monitors

Mounting Options

The vibration insulating Isolation Positioner/Decoupler™ (Iso­Pod™) table stand allows tilting of the monitor. The stand
spring can be attached to three mounting points on the 8331A
enclosure, allowing the Iso-Pod to be used on one vertical and
two horizontal positions.

Aim the monitor so that its acoustic axis points towards the
listening position (see Figure 4). Place the monitors symmetrically
at equal distances from the listening position. If possible, place
the listening position on the left-right centerline of the room
(see Figure 5). When a monitor is placed far away (1.0-2.2 m,
3-7 ft) from the acoustically hard wall behind the monitor, an
acoustic reflection from the wall may cause cancellation of low
frequencies and reduce the bass output.

Minimize reflections by placing the monitors away from
acoustically reflective surfaces. Acoustic reflections from
objects like desks, cabinets and computer monitors can cause
unwanted coloration and blurring of the sound image. Putting
the monitors on stands behind and above a mixing console
usually improves the response over placing monitors on a meter
bridge. Symmetrical positioning of the sound reflecting objects
maintains a balanced soundstage (see Figure 5).

A wide variety of ceiling and wall mounts are available through
your Genelec dealer. Genelec 8331A can be fitted with König &
Meyer monitor mounts using two M6 x 10 mm threaded holes
on the enclosure back. There is also a 3/8 in UNC threaded hole
in the base of the monitor. Consult the Genelec Accessories
Catalogue at www.genelec.com or your local distributor/dealer
for information.

Front Panel Light

Normally, the light on the front panel is green, indicating normal
operational mode. Red and yellow colours are used to indicate
special situations. See Table 2.

Use With Subwoofers

In situations requiring deeper fundamental response or
multichannel bass management, Genelec recommends
using the 7300 series subwoofers. For more detailed system
configuration and matching products, please consult the on-line
Genelec Product Selection Tool at www.genelec.com.

Maintenance

There are no user serviceable parts inside the monitor.
Maintenance or repair must only be done by Genelec certified
service personnel. The monitor enclosure must not be opened.
Opening the monitor may lead to loss of the individual monitor
factory calibration and damage to components.

Safety Considerations

Although the 8331A has been designed in accordance with
international safety standards, to ensure safe operation and
to maintain the monitor under safe operating conditions, the
following warnings and precautions must be observed:

•  Servicing and adjustment must only be performed by
certified Genelec service personnel. The monitor enclosure
must not be opened.

•  Do not use this product with an unearthed mains cable
or a mains connection without the protective earth contact
as this may lead to personal injury.

•  To prevent fire or electric shock, do not expose the unit
to water or moisture.

•  Do not place any objects filled with liquid, such as vases
on the monitor or near it.

5

•  Note that the amplifier is not completely disconnected

Genelec Oy 8331 11 Mar17

0°

60°

15°

30°

45°

65

70

75

80

85

90

95

dB SPL

85

90

95

dB SWL

80

Genelec Oy 8331A 12 May 2017

80

85

90

BASS ROLL-OFF

TREBLE TILT

80

85

90

80

85

90

DESKTOP LF

BASS TILT

dB SPL

from the AC mains service unless the mains power cord is
removed from the monitor loudspeaker or the mains outlet.

•  Free flow of air behind and around the monitor is
necessary to maintain sufficient cooling. Do not obstruct
airflow around the monitor.

WARNING!

The 8331A is capable of producing sound pressure levels in
excess of 85 dB, which may cause hearing damage. Sound
exposure level integrated over an 8 hour working day should
be limited to 80 dB(A) to reduce the risk of permanent hearing
damage. For each 3 dB increase in sound exposure, half the
exposure time should be observed (equal energy).

Guarantee

The Genelec 8331A is guaranteed for two years against
manufacturing faults or defects altering performance. Refer to
the reseller for full sales and guarantee terms.

Compliance To FCC Rules

Note: This equipment has been tested and found to comply
with the limits for a Class B digital device, pursuant to part
15 of the FCC Rules. These limits are designed to provide

reasonable protection against harmful interference in a
residential installation. This equipment generates, uses and
can radiate radio frequency energy and, if not installed and
used in accordance with the instructions, may cause harmful
interference to radio communications. However, there is
no guarantee that interference will not occur in a particular
installation. If this equipment does cause harmful interference
to radio or television reception, which can be determined by
turning the equipment off and on, the user is encouraged to
try to correct the interference by one or more of the following
measures:

•  Reorient or relocate the receiving antenna.

•  Increase the separation between the equipment and

receiver.

•  Connect the equipment into an outlet on a circuit

different from that to which the receiver is connected.

•  Consult the dealer or an experienced radio/TV technician

for help.

Modifications not expressly approved by the manufacturer
could void the user’s authority to operate the equipment under
FCC rules.

100

200

20

50

500

Figure 6. The curves above show the effect of the “Bass Tilt”,
“Treble Tilt”, “Desktop Low Frequency” and “Bass Roll-Off” controls
on the free field response of the 8331A.

Figure 8. The curves above show the horizontal directivity
characteristics of the 8331A.

6

1k 2k

5k

Frequency Hz

10k

20k

100

200

20

50

500

1k 2k

5k

Frequency Hz

10k

Figure 7. Frequency responses at 0, 15, 30, 45 and 60 degree
angles and power response in full space. Input level -20 dBu.

Figure 9. The curves above show the vertical directivity
characteristics of the 8331A.

20k

100

Frequency Hz

Genelec Oy 8331 16 May 2017

ms

5

0

10

15

35

20

25

30

40

200

50

500

1k 2k

5k

10k

20k

Figure 10. The curve above shows the delay variation of the 8331A
as a function of frequency.

SYSTEM SPECIFICATIONS

Lower cut-off frequency, –6 dB < 45 Hz

Upper cut-off frequency, –6 dB > 37 kHz

Accuracy of frequency response, ± 1.5 dB 58 Hz – 20 kHz

Maximum short term sine wave acoustic output on axis in half space, averaged from
100 Hz to 3 kHz at 1 m

Maximum long term RMS acoustic output in the same conditions with IEC weighted
noise (limited by driver protection circuit) at 1 m

Maximum peak acoustic output per pair in a listening room with music material at 1 m 110 dB

Self generated noise level in free space at 1 m on axis (A-weighted) ≤ 0 dB

Harmonic distortion at 85 dB SPL at 1 m on axis

Freq: 50…100 Hz
> 100 Hz

Drivers

Bass
Midrange
Treble

Weight 6.7 kg (15 lb)

Dimensions

Height including IsoPod stand
Height without IsoPod
Width
Depth

≥ 104 dB SPL

99 dB SPL

< 2 %
< 0.5 %

Dual 130 x 65 mm (51/8 x 25/8 in) oval cones
90 mm (31/2 in) cone (coaxial)
19 mm (3/4 in) metal dome (coaxial)

305 mm (12 in)
285 mm (111/4 in)
189 mm (71/2 in)
212 mm (83/8 in)

AMPLIFIER SECTION

Bass amplifier short term output power
Midrange amplifier short term output power
Treble amplifier short term output power
(Long term output power is limited by driver protection circuitry)

Amplifier system THD at nominal output <0.05%

Mains voltage 100-240 VAC 50/60 Hz

Power consumption

ISS active
Idle
Full output (short term)

72 W
36 W
36 W

< 0.5 W
4 W
60 W

7

SIGNAL PROCESSING

8331A

Analog signal input connector XLR female, balanced 10 kOhm

Maximum analog input signal
Analog input sensitivity (100 dB SPL at 1 m)
Analog input sensitivity control

Digital signal input connector XLR female 110 Ohm
Digital signal output / Thru connector XLR male 110 Ohm

Digital audio input

Word length

Sample rate
Digital input sensitivity (100 dB SPL at 1 m)
Digital input maximum attenuation

Control network

Type

Connection

Crossover frequencies

Bass/Mid

Mid/Treble

GLMTM software frequency response adjustment*

Parametric notch filters

Shelving filters

System room response calibration Genelec GLM AutoCal™, GLMTM manual, Stand-alone*

* The notch and shelving lters adjustments, AutoCalTM and GLM

TM

manual system calibration features are part of the Genelec Loudspeaker Manager (GLMTM) software

pin 1 gnd
pin 2 non-inverting
pin 3 inverting

+24.0 dBu

-6 dBu
Adjustable from +36 to -6 dBu

AES/EBU Single Wire
AES/EBU Single Wire

16 - 24 bits
32 - 192 kHz

-30 dBFS
42 dB

Proprietary GLM™ network
2 RJ45, CAT5 cables

500 Hz
3 kHz

16
2 LF and 2 HF

Genelec Document D0131R001 Copyright Genelec Oy 4.2017. All data subject to change without prior notice.

International enquiries:

Genelec, Olvitie 5

FIN-74100, Iisalmi, Finland

Phone [phone]

Fax [phone]

Email [e-mail]

In the U.S. please contact:

Genelec, Inc., 7 Tech Circle

Natick, MA 01760, USA

Phone [phone]

Fax [phone]

Email [e-mail]

In Sweden please contact:

Genelec Sverige

Ellipsvägen 10B

P.O. Box 2306

S-127 02 Skärholmen

Phone [phone]

Fax [phone]

Email [e-mail]

www.genelec.com

In China please contact:

Beijing Genelec Audio Co.Ltd

B33 - 101

Universal Business Park

No. 10 Jiuxianqiao Road

Chaoyang District

100015 Beijing, China

Phone [phone]

Email [e-mail]