Genelec HT320AC User Manual

HT320AC

Operating Manual

Genelec HT320AC
Active Home Theater System

Genelec HT320AC Active Home Theater System

System

The Genelec HT320AC is a dedicated

center channel loudspeaker for three

channel (LCR) and Surround systems. Its

compact cabinet has been designed for

optimum placement in the limited space

above or below a video monitor or screen.

The HT320AC is a three-way active loud-

speaker including drivers, multiple power

amplifiers and active cross overs. The

amplifiers and crossovers are built into a

separate rack mount chassis.

The system is designed for room vol-

umes up to 250 m3 / 8800 ft3 with maximum

listening distances up to 6.1 - 7.6 meters

(20-25 ft) The HT320AC is recommended

to be flush mounted into the wall structure,

but it can also be used as a free-standing

loudspeaker.

The unique Directivity Control Wavegui-

deTM (D C WTM) Tec hno l ogy p rov ides

excellent stereo imaging and frequency

balance even in difficult acoustics envi-

ronments. The fast, low distortion amplifiers

are capable of driving the system to peak

output levels in excess of 124 dB SPL at 2

m with program signals. Versatile crossover

controls allow for precise matching of the

system to different acoustic conditions.

Drivers

The bass frequencies are reproduced by

two 250 mm (10") bass drivers loaded with

a 110 liter vented box. The -3dB point is

33 Hz and the low frequency response

extends down to 29 Hz (-6 dB). The mid-

range frequencies are reproduced by a pro-

prietary 130 mm (5") direct radiating cone

driver loaded with a DCWTM. The high fre-

quency driver is a 25 mm (1") metal dome

also loaded by a DCWTM. The HT320AC is

magnetically shielded in order to minimise

interference with video monitors

Crossover filters

The crossover frequencies of the active

crossover network are 410 Hz and 3.0 kHz.

Special calibrated controls are included in

the crossover in order to obtain a uniform

frequency balance under different acoustic

conditions. ; the Bass, Midrange and Treble

Level controls operate in 1 dB steps. Fur-

thermore, the low frequency Tilt and Roll-

Off controls both have four 2 dB steps to

allow refined LF response tailoring

A high-pass filter is included in the LF

channel to protect the woofer from sub-

sonic signals. The crossover network is

driven by an active balanced input stage

.

fed by a 3 pin XLR. Variable input sen-

sitivity allows for accurate to the signal

source output.

Amplifiers

The bass, midrange and treble ampli-

fiers produce 400 W, 120 W and 120 W,

respectively of short term power with very

low THD and IM distortion values. The

negative output impedance of the woofer

amplifiers improves acoustic transients.

The system incorporates special circuitry

for driver overload protection and amplifier

thermal protection.

Installation

Each HT320AC loudspeaker is supplied

with a separate amplifier unit in a 19" 12 U

rack mount chassis, a 10 meter connecting

cable set, a mains cable and an operating

manual. Once unpacked, place the loud-

speaker in its required listening position,

taking note of the line of the acoustic axis

(see figure 1) and install the amplifier

into a standard 19" rack. Sufficient cool-

ing for the amplifier must be ensured. The

minimum clearance for the amplifier is 10

centimeters (4”) to any object. The space

adjacent to the amplifier must either be

ventilated or sufficiently large to dissipate

Speaker mounting

G

E

N

E

L

E

C

> 1 m

500 mm
(19 3/4 )″

h2

h2=

GENELEC

> 1 m

950 mm (37 3/8 )″

350 mm
(13 3/4

)″

453 mm
(17 7/8

)″

200 mm
(7 7/8 )″

h1

h1=

position

Free field anechoic
response

In a corner -2 dB -2 dB -2 dB None None

Flush mounted in a
wall structure

Table 1. Suggested t one control settings in some typical situations

Bass

roll-off

None None None None None

None None -4 dB None None

Bass

tilt

Bass
level

Midrange

level

Treble

level

Figure1. Locati on of the acoustic axis

heat so that the ambient temperature does

not rise above 35 degrees Celsius (95°F).

When soffit mounting the units it should

be noted that the cable connectors require

10 cm (4") of free space behind both the

loudspeaker and the amplifier.

Before connecting up, ensure that the

mains switch is off (see figure 2). Check

that the mains voltage selector is correctly

set and that the appropriate fuse is fitted.

The connec ting cables b etween the

amplifier and the loudspeaker cabinet

have Speakon 8- and 4-pole connectors.

Push the 4-pole connector in and turn it

clockwise until the retaining clip clicks. The

8-pole (thicker) type is connected by push-

ing the connector in, turning it clockwise

and tightening the blue locking collar at the

end of the connector.

Audio input to the amplifier is made via a

10k Ohm balanced (XLR) lead, but unbal-

anced leads may be used as long as pin 3

is grounded to pin 1 of the XLR (see figure

3). Once connection has been made, the

loudspeakers are ready to be powered up.

Setting the input sensitivity

Adjustment of the input sensitivity of each

loudspeaker can be made to match that of

the signal source, by use of the input sen-

Figure 2. Ampli fier panel layout of the HT320AC

sitivity control on the amplifier panel (see

figure 2). A small screwdriver is needed for

the adjustment. The manufacturer default

setting for this control is -6 dBu (fully clock-

wise) which gives an SPL of 100 dB @1 m

with -6 dBu input level. Note that to get the

full output level of 120 dB SPL, an input

level of +14 dBu is needed at this setting.

Autostart and remote control

Th e HT3 20AC is equi ppe d wit h an

“Autostart” function, which automatically

turns the amplifier to “standby” mode if

an input signal has not been detected for

approximately thirty minutes, and back to

“on” mode when the signal returns. The

function can be deactivated by turning

the “AUTOSTART” dip switch to “OFF”. A

three-colour LED on the loudspeaker indi-

cates the amplifier status: green for “on”

and yellow for “standby”.

The amplifier mode can also be switched

by a remote control unit connected to the

respective inputs on the amplifier. Two pairs

of connectors are provided, 1 and 2 for a

12 V DC type remote control, and 3 and 4

for an external switch or relay type control.

Do not connect two remote controls to the

loudspeaker at the same time. Activate the

function by turning the "REMOTE CON-

Figure 3. RCA t o XLR cable

TROL" dip switch on the amplifier panel to

"ON". Note that the remote control func-

tion overrides the “autostart” dip switch

function.

Setting the tone controls

The acoustic response of the system may

also have to be adjusted to match the

acoustic environment. The adjustment is

done by setting the five tone control switch

groups 'Bass Tilt', 'Bass Roll-Off', 'Bass

Level', 'Mid Level' and 'Treble Level' on the

amplifier. The manufacturers default set-

tings for these controls are 'All Off' to give

a flat anechoic response. See Table 1 for

suggested tone control settings in differing

acoustic environments. Figure 8 shows

the effect of the controls on the anechoic

response. Always start adjustment by set-

ting all switches to the 'OFF' position. Then

set only one switch to the 'ON' position to

select the response curve required. If more

Figure 4: Flush mounting the loudspe aker in

FACING PANEL

FIXED TO THE WALL

(50-100 mm / 2-4")

RUBBER GASKET

(5-10 mm / ¼-½")

SPEAKER

WALL

CONCRETE

STRUCTURE

VIBRATION

ISOLATORS

f ~ 2-8 Hz

MULTI-LAYERED WALL

(WOOD, CONCRETE, BRICKS

)

VIBRATION

ISOLATORS

f ~ 2-8 Hz

CONCRETE WALL

SAND

BAGS

VIBRATION

ISOLATORS

f ~ 2-8 Hz

HEAVY WOODEN WALL

ABSORBING

MATERIAL

a wall constr ucted of wood

Figure 5: Flush mounting the loudspe aker in
a wall constr ucted of concrete

Figure 6: Flush mounting the loudspe aker
in a wall constructed of a combination of
materials.

than one switch is set to 'ON' (within one

switch group) the attenuation value is no

longer accurate.

Vertical / horizontal mounting

Genelec HT320AC can be mounted ver-

tically or horizontally. If the loudspeaker's

orientation is changed, the DCW™ plate

must be rotated so that the treble and mid-

range drivers remain vertically aligned with

the mid driver at the bottom of the DCW™.

Remove the four corner screws of the

DCW™ (use a 4 mm Allen key) and pull

the plate carefully out without stressing the

wires and the gasket. Rotate the plate 90

degrees in the appropriate direction and

remount the screws.

Flush mounting

Th e HT3 2 0AC can be us ed fl ush

mounted into the wall structure, which

offers some acoustical benefits. No cabi-

net edge diffraction will occur, resulting

in an improved response, especially at

midrange frequencies. Low frequency

reflections from the wall behind the loud-

speaker can be avoided, which improves

the low frequency response and efficiency

and allows the loudspeaker to work in

half space conditions. In terms of instal-

lation and orientation, the loudspeaker’s

acoustical axis (See figure 1) should point

directly to the listening position. The loud-

speaker should be vertically aimed so that

the acoustical axis of the loudspeakers

meet around ear height at the reference

listening position. In the horizontal plane

the loudspeakers should be positioned

according to the multichannel (ITU-R

BS.775-1) placement recommendation.

The ceiling, side walls and especially the

rear wall should be acoustically absorbent

Figure 7: Covering the gap betwee n the
wall and the loudspeaker cabinet.

at low frequencies. The wall in which the

loudspeakers are mounted should have a

high acoustical mass to properly implement

half space radiation at low frequencies and

be angled so that the loudspeakers are

correctly aimed. However, the loudspeak-

ers should not be mounted too high as this

increases the required vertical tilt of the

speaker (maximum tilt angle < 20 degrees)

and reduces the optimum listening area.

Great care should be taken over how the

loudspeaker is mounted into the wall. Note

the following:

A space 50 to 100 mm (2 to 4”) wide

can be left around the loudspeaker. Cover

the space around the loudspeaker with a

facing panel that should be fixed to the wall.

Leave a gap of about 5 to 10 mm (¼ to ½”)

between the loudspeaker and the panel. Fill

this gap with a soft rubber gasket to allow

for possible movement (see figure 6).

Ensure that the loudspeaker cables can

reach the rear of the loudspeaker cabi-

nets.

Regardless of the type of front wall con-

struction the loudspeaker cabinet should

be mounted on vibration isolators, with a

resonant frequency of 2 to 8 Hz, to pre-

vent vibrations from being transmitted to

the wall and impairing the low frequency

performance.

If a heavy wooden front wall construc-

tion is used, the space around the cabi-

net should be filled with absorbent min-

eral wool or foam plastic. The wooden

wall structure must be heavily braced to

achieve sufficiently high mass and rigidity

(see figure 4).

Figure 8: The curves above show the effect of the ‘bass’, ‘mid ’ and

+80

+85

+90

+80

+85

+90

+80

+85

+90

20

20k

50

100 200 500

1k 2k

5k

10k

BASS TILT

BASS LEVEL

BASS ROLL-OFF

MID LEVEL

TREBLE LEVEL

Hz

dBr

AUDIO PRECISION 1038BCANEC vs 22 OCT 02LEVEL(dBr) FREQ(Hz)

+55

+60

+65

+70

+75

+80

+85

+90

+95

20

20k

50

100 200 500

1k 2k

5k

10k

0°

30°

15°

45°

dBr

Hz

AUDIO PRECISION 1038BCANEC vs 22 OCT 02LEVEL(dBr) FREQ(Hz)

‘treble’ level con trols, and the ‘bass til t’ and ‘bass roll-off ’ controls
on the free field response of the HT320AC, measured at 2 m.

Figure 9: The curves above show the hor izontal directivity
character istics o f the HT320AC in its horizontal configuratio n
measured at 2 m.

In a solid wall (e.g. concrete) structure,

the space around the cabinet should be

filled with either absorbent mineral wool or

sand bags (see figure 5).

The wall can also be constructed of a

combination of materials to achieve high

acoustical structural mass that will disable

low frequency sound propagation and pro-

vide high LF sound isolation (see figure 6).

Acoustic consultants will be able to provide

details and design these structures.

Ensure that the cabinet is flush with the

surface of the wall. Discontinuities in the

loudspeaker mounting wall will cause dif-

fraction, which leads to inferior frequency

response and stereo imaging. So, if a deco-

rative cloth frame is used to cover the wall,

make sure that the edges adjacent to the

speaker are less than 20 mm (3/4”) deep.

The cloth must be very thin Tricot or an

acoustically transparent material other-

wise the high frequency response of the

system will be adversely affected. Genelec

approved cloth grilles are available.

Mode indicator LEDs

The Genelec HT320AC is provided with a

three-colour indicator LED on the DCW™

panel. When the LED is green, it indicates

that the loudspeaker is ready for use.

Standby mode is indicated by yellow colour.

Amplifier clipping is indicated by a blinking

red light and thermal protection mode by

a constant red light. If clipping is indicated

reduce the signal level so that the LED stops

blinking. If the red LED stays on constantly,

switch off the loudspeaker and the audio

source and let the amplifier cool down.

Check that the ventilation around the ampli-

fier is not blocked. There should be a clear-

ance of more than 100 mm (4”) between the

amplifier face panel and any solid surface at

the back. If the red light does not come off,

contact authorised Genelec service.

The LED can be deactivated if you find

it disturbing in a darkened room by turning

both the "POWER LED" and "STANDBY

LED" switches on the amplifier panel to

"OFF".

2. Do not use the loudspeaker with an

unearthed mains cable or unearthed

mains connection as this may lead to

personal injury.

3. This loudspeaker is capable of

producing sound pressure levels in

excess of 85 dB, which may cause

permanent hearing damage.

4. Free flow of air around the amplifier is

necessary to maintain sufficient

cooling. Do not obstruct airflow around

the amplifier.

5. 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 or near the

Maintenance

No user serviceable parts are to be found

within the amplifier unit. Any maintenance

or repair of the unit should only be under-

taken by qualified service personnel.

loudspeaker or the amplifier.

6. Note that the amplifier is not

completely disconnected from the AC

mains service unless the mains cable

is removed from the amplifier or the

mains outlet.

Safety considerations

Although the HT320AC has been designed

in accordance with international safety

standards, to ensure safe operation and to

Order code

Protective grille 1038-409BC

maintain the instrument under safe operat-

ing conditions, the following warnings and

cautions must be observed:

This product is supplied with one year

guarantee against manufacturing faults or

be performed by qualified service

personnel. The amplifier must not be

1. Servicing and adjustment must only

defects that might alter the performance of

the HT320AC unit. Refer to supplier for full

sales and guarantee terms.

opened.

Accessories

Guarantee

HT320AC Operating Manual

SYSTEM SPEC IFIC ATIONS

HT320AC

Lower cut-off frequency, -3 dB
Upper cut-off frequency, -3 dB
Free field frequency response
of system

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

Maximum long term RMS acoustic output
in same conditions with IEC-weighted noise
(limited by driver unit protection circuit)

Maximum peak acoustic output per pair above
console with music materia

Self generated noise level in free field @1m
on axis

Harmonic distortion at 95 dB SPL at 1m on
axis:

Drivers
Bass
Midrange
Treble
All drivers are magnetically shielded

Weight
Speaker cabinet
Amplifier

Speaker cabinet dimensions
Height
Width
Depth

Amplifier dimensions
Height
Width
Depth

*Without connecting cable s. Cable connectors require
additional 100 mm (4") of space behind the speaker and the
amplifier

<33 Hz
>20 kHz
35 Hz - 20 kHz (±2.5 dB)

@1m >120 dB SPL

@1m >116 dB SPL

@ 2m >124 dB

<15 dB (A weighted)

freq. 50...100 Hz <1%
freq. >100 Hz <0.5%

2 x 250 mm (10") cone
130 mm (5") cone
25 mm (1") metal dome

60 kg (130 lb)
14 kg (31 lb)

350 mm (13 3/4")
950 mm (37 3/8")
453 mm (17 7/8")*

530 mm (20 7/8") (12 U)
480 mm (8 7/8")
113 mm (4 7/16")*

AMPLIFIER S ECTI ON

HT320AC

Bass amplifier short term output power 2 x 200 W (4 Ohm load)

Midrange amplifier short term output power 120 W (8 Ohm load)

Treble amplifier shor t term output power 120 W (8 Ohm load)

Long term output power is limited by driver unit protection circuitry.

Slew rate 80V/µs

Amplifier system distortion at nominal output
THD
SMPTE-IM
CCIF-IM
DIM 100

<0.05%
<0.05%
<0.05%
<0.05%

Signal to Noise ratio, referred to full output
Bass
Midrange
Treble

>100 dB
>100 dB
>100 dB

Mains voltage 100/200V or 115/230V

Voltage operating range nominal ±10%

Power consumption
Idle
Full output

60 W
500 W

CROSSOVER SECTION

HT320AC

Input connector XLR female pin 1 gnd

Input impedance 10 kOhm

Input level for 100 dB SPL output @1m variable from +6 to -6 dBu

Input level for maximum short term output variable from +26 to +14

Subsonic filter 18 dB/octave

Ultrasonic filter 12 dB/octave

Crossover frequency
Bass/Mid
Mid/Treble

Crossover acoustical slopes 24 - 32 dB/octave

Crossover level control operating
range in 1 dB steps
Bass
Mid
Treble

Bass roll-off control in 2 dB steps from 0 to -8 dB @33 Hz

Bass tilt control in 2 dB steps from 0 to -8 dB @80 Hz

The 'CAL' position is with all tone controls set to 'off' and input sensitivity
control to maximum.

pin 2 +
pin 3 -

dBu for 120 dB SPL @1m

below 33 Hz

above 25 kHz

410 Hz
3 kHz

from 0 to -6 dB
from 0 to -6 dB
from 0 to -6 dB

Genelec Docu ment D0069R001 Copyrig ht Genelec Oy 2.2006. All data subject to change without prior notic e

Inter national e nquiries:

Genele c, Olvitie 5

FIN-74 100, Iisal mi, Finlan d

Phone [phone]

Fax [phone]

Email genele [e-mail]

In the U.S. please c ontact:

Genele c, Inc., 7 Tech C ircle

Natick, MA 01760 , USA

Phone [phone]

Fax [phone]

Email genele [e-mail]

In Chi na please contact:

Beijin g Genelec Audio Co. Ltd.

Jianwa i SOHO, Tower 12, R oom 2306

39 Eas t 3rd Ring Road

Chaoyang District

Beijin g 100022, China

Phone [phone], Fax [phone]

www.genelec.com

In Sweden ple ase contact

Genelec Sveri ge

Ellipsvägen 10 B

P.O. Box 5521, S-141 05 Huddinge

Phone [phone]

Fax [phone]

Email info@gen elec.com