Genelec 7070-A Owners manual

Genelec 7060B, 7070A and 7071A
Active Subwoofers

Operating Manual

LSE Series

General description

Genelec 7060B, 7070A and 7071A are pow-

erful active subwoofers, incorporating all the

amplifier and crossover electronics needed

for bass management and reproduction in

modern 6.1 or 5.1 channel surround sound

or traditional stereo systems. Their 19 to

120 Hz (±3 dB) frequency range, ample

sound pressure capability and versatile

connections make these subwoofers ideal

companions for Genelec's active monitoring

speakers.

Bass management unit

The built-in bass management unit has six

signal input and output channels (L/C/R Front

and L/C/R Rear), a discrete LFE signal input

and a summed signal output, providing great

flexibility and easy connection in all monitor-

ing environments.

The active crossover contained in the bass

management unit splits the input signals into

low and high frequency components at 85

Hz. Frequencies below 85 Hz are directed to

the subwoofer and frequencies above 85 Hz

to the main speakers.

The low pass section sensitivity can be

adjusted from +12 dBu to -6 dBu to allow

easy subwoofer level matching with various

main speakers. All outputs have 0 dB pass-

band gain.

The low pass frequency of the LFE input

channel can be set to 85 Hz, 120 Hz or 85 Hz

with "Redirect" function that routes LFE con-

tent above 85 Hz to the front center monitor.

The input sensitivity of the LFE channel can

be set to 0 dB or +10 dB.

Balanced XLR connectors are used for the

system audio inputs and outputs.

Two "Bass Roll-Off" switches are included

to provide a flat bass response in all acous-

tical environments, enabling adjustments of

the subwoofer response in three -2 dB steps.

Two phase matching switches in the crosso-

ver allow compensation for the delay which

occurs if the subwoofer is placed away from

the main speakers, or for other speaker sys-

tems phase behaviour. Four settings are pro-

vided between 0° and -270°. An 85 Hz test

tone generator is included to help achieve

accurate crossover phase alignment.

Installation

Each subwoofer is supplied with a mains cable

and an operating manual. Once unpacked,

place the subwoofer in a suitable location (for

more details see the "Positioning" section).

Before connecting the audio signals, ensure

that both the subwoofer and the main moni-

tors are switched off. Check that the voltage

selector switch is set according to your local

mains voltage (subwoofers sold in Europe

have a fixed 230V setting). Connections are

easier to make if you roll the subwoofer on

its side with the connector panel facing up.

Use this position only for making the con-

nections and roll the subwoofer back to its

normal upright position before use. Audio

connections to the subwoofer are made via

balanced XLR connectors. An unbalanced

source can also be used with a special RCA

to XLR cable; the correct connection for the

cable is shown in Fig. 2. However, we recom-

mend the use of balanced cables and con-

nectors due to their better noise immunity.

The connectors are arranged in three rows

on the connector panel (see Fig. 1):

Top row

LFE IN / SUM IN: Use this connector for

the LFE or .1 output channel of a 5.1-

or 6.1-channel dis crete surround sound

source, or the SUM OUT signal from the

"master" subwoofer in a daisy-chained mul-

tiple subwoofer configuration. Note that the

"subwoofer out" channel of an analogue

7060B, 7070A and 7071A Active Subwoofers

matrix surround decoder (Dolby Surround,

Dolby Pro Logic) should not be connected to

the "LFE IN" input. See section "Subwoofer

in analogue matrix sound systems".

SUM OUT: Use this output connector when

you want to link another subwoofer to your

system. "SUM OUT" carries an unfiltered sum

of signals combined from all input channels.

See section "Using multiple subwoofers".

Middle row

FRONT L, C, R CHANNELS IN/OUT: Use

these connectors for the Front Left, Center

and Right channels of a surround sound

system or the Left and Right channels of a

Stereo system. Connect line level signal

cables from your signal source to their respec-

tive "LEFT IN", "CENTER IN" and "RIGHT IN"

connectors. Then connect the subwoofer to

your main monitors with XLR cables from the

"LEFT OUT", "CENTER OUT" and "RIGHT

OUT" connectors. All "L, C and R OUT" chan-

nels are high pass filtered with the filtering

frquency fixed at 85 Hz (12 dB/octave).

Bottom row

REAR L, C, R CHANNELS IN/OUT: Use

these connectors for the Rear Left, Center

and Right channels of a surround sound

system. The connection is made in the same

way as with the Front channels. Also these

channels are high pass filtered at 85 Hz.

Once all connections have been made, the

subwoofer and main monitors are ready to be

powered up.

Positioning in the room

The placement of the subwoofer in the room

affects the overall frequency response and

sound level of the system dramatically, as at

low frequencies the effects of the room are

strong. Even a slight change in the subwoof-

er's location can make a marked difference

in the frequency balance and often patient

and methodical experimentation and testing

is needed to find the optimum placement.

The placement will affect the phase dif-

ference between the main monitors and the

subwoofer, and also the bass roll-off rate.

These effects can be compensated by the

use of the controls in the amplifier unit; but

we recommend that at first you leave the

switches untouched and concentrate on find-

ing the position where the subwoofer gives

the smoothest response, and only then use

the controls to fine-tune the balance and

phase alignment between the subwoofer and

the main monitors.

To begin with, place the subwoofer slightly

offset from the center of the front wall. The

recommended distance to the wall is less

than 60 cm / 24" measured from the sub-

woofer's driver (See Fig. 3). This position

gives increased acoustic loading (and SPL)

due to the proximity of the front wall and floor.

Cancellations from the front wall and floor are

also avoided. Front wall cancellation for the

85 Hz high pass filtered main speakers can

be eliminated by placing them at least 110

cm / 43" away from the front wall. In a mul-

tichannel system the main monitors should

ideally be positioned symmetrically and at an

equal distance from the listening position.

If the frequency balance is not right, try

moving the subwoofer slightly to the left or

right so that different room modes are excited

at different levels. Positioning the subwoofer

close to a corner will boost the bass level

at lower frequencies and may cause asym-

metrical spatial imaging. If you are using two

subwoofers, try placing them asymmetrically

relative to the side walls. Sometimes moving

the subwoofers apart into the front corners

helps with problematic rear wall reflections

and the loss of mutual coupling is compen-

sated by the bass boost caused by corner

positioning.

Figure 3. Recommended distances to
the front wall

Figure 1. 7070A's connector panel, connectors a nd controls.

Figure 2. XLR to RCA connector for
unbalanced operation.