Nilfisk EQU User Manual

User's Manual

EQU Series

+18

0dB

-

15/31 Band Graphic Equalizer

+18

0dB

-

R

LTO

www.altoproaudio.com

Version 1.0 April 2002

English

SAFETY RELATED SYMBOLS

CAUTION

RISK OFELECTRIC SHOCK

DO NOTOPEN

This symbol, wherever it appears, alerts you
to the presence of uninsulated dangerous voltage
inside the enclosure-voltage that may be su­fficient to constitute a risk of shock.

This symbol ,wherever it appears ,alerts you
to important operating and maintenance
instructions in the accompanying literature .
Read the manual .

Protective grounding terminal .

Alternating current /voltage .

Hazardous live terminal .

ON: Denotes the apparatus turns on .

OFF: Denotes the apparatus turns off ,because of

using the single pole switch ,be sure to unplug the
AC power to prevent any electric shock before you
proceed your service .

WARNING: Describes precautions that should
be observed to prevent the danger of injury or
death to the user .

CAUTION: Describes precautions that should
be observed to prevent danger of the apparatus .

WARNING

Power Supply

Ensure the source voltage matches the voltage of

the power supply before turning ON the apparatus.
Unplug this apparatus during lightning storms or when
unused for long periods of time .

External Connection

The external wiring connected to the output hazardous
live terminals requires installation by an instructed
person, or the use of ready-made leads or cords.

Do not Remove any Cover

There are maybe some areas with high voltages

inside , to reduce the risk of electric shock, do not

remove any cover if the power supply is connected.

The cover should be removed by the qualified personnel

only.

No user serviceable parts inside.

Fuse

To prevent a fire, make sure to use fuses with specified

standard (current, voltage, type). Do not use a different

fuse or short circuit the fuse holder.

Before replacing the fuse, turn OFF the andapparatus

disconnected the power source.

Protective Grounding

Make sure to connect the protective grounding to prevent

any electric shock before turning ON the apparatus.

Never cut off the internal or external protective grounding

wire or disconnect the wiring of protective grounding
terminal.

Operating Conditions

This apparatus shall not be exposed to dripping or
splashing and that no objects filled with liquids,
such as vases, shall be placed on this apparatus.
To reduce the risk of fire or electric shock, do not
expose this apparatus to rain or moisture.
Do not use this apparatus near water.
Install in accordance with the manufacturer's
instructions. Do not install near any heat sources
such as radiators, heat registers, stoves, or other
apparatus (including amplifiers) that produce heat.
Do not block any ventilation openings.
No naked flame sources, such as lighted candles,
should be placed on the apparatus.

IMPORTANT SAFETY INSTRUCTIONS

Read these instructions.

Follow all instructions.
Keep these instructions.
Heed all warnings.
Only use attachments/accessories specified by the

manufacturer.

Power Cord and Plug

Do not defeat the safety purpose of the polarized
or grounding type plug. A polarized plug has two
blades with one wider than the other. A grounding
type plug has two blades and a third grounding
prong. The wide blade or the third prong are provided
for your safety. If the provided plug does not fit into
your outlet, consult an electrician for replacement
of the obsolete outlet.
Protect the power cord from being walked on or
pinched particularly at plugs, convenience receptacles ,
and the point where they exit from the apparatus.

Cleaning

When the apparatus needs a cleaning, you can blow
off dust from the apparatus with a blower or clean
with rag etc. Don't use solvents such as benzol,
alcohol, or other fluids with very strong volatility and
flammability for cleaning the apparatus body.
Clean only with dry cloth.

Servicing

Refer all servicing to qualified personnel. To reduce
the risk of electric shock, do not perform any servicing
other than that contained in the operating instructions
unless you are qualified to do so .

Servicing is required when the apparatus has
been damaged in any way ,such as power supply
cord or plug is damaged , liquid has been spilled
or objects have fallen into the apparatus, the
apparatus has been exposed to rain or moisture,
does not operate normally, or has been dropped.

11

Preface

Dear Customer:

Thanks for choosing LTO Graphic Equalizer and thanks for choosing one of the results of LTO AUDIO
TEAM job and researches.

For our LTO AUDIO TEAM, music and sound are more than a job...are first of all passion and let us say...our
obsession!
We have been designing professional audio products for a long time in cooperation with some of the major
brands in the world in the audio field.

The line presents unparalleled analogue and digital products made by Musicians for Musicians in ourLTO
R&D Centr s in Italy, Netherlands, United Kingdom and Taiwan. The core of our digital audio products is ae
sophisticated DSP (Digital sound processor) and a large range of state of the art algorithms which have been
developed by our Software Team for the last 7 years.

Because we are convinced you are the most important member of LTO AUDIO TEAM and the one confirming
the quality of our job, we would like to share with you our work and our dreams, pay attention to your suggestions
and your comments.
Following this idea we create our products and we will create the new ones! From our side, we guarantee you
and we will guarantee you also in future the best quality, and the best fruits of our continuous researches
and the best prices.

Our LTO Graphic Equalizer is the result of many hours of listening and tests involving common people, area
experts, musicians and technicians.
The results of this effort is a high-end Graphic Equalizer which will provide a permanent precise equalization to
the musician, performer, studio engineer and sound contractor .

Nothing else to add, but that we would like to thank all the people that made the LTO Graphic Equalizer a
reality available to our customers, thank our designers and all LTO staff, there to make possible the realization
of products containing our idea of music and sound and there to support you, our customers, in the best way,
conscious that you are our best richness.

Thank you very much.

LTOAUDIOTEAM

2

TABLE OF CONTENT

1. INTRODUCTION ..........................................................................................................................4

2. FEATURE LIST ............................................................................................................................4

3. CONTROL ELEMENTS ............................................................................... ..................................4

3.1 The Front Panel

3.2 The Rear Panel

4. INSTALLATION & CONNECTION ..................................................................................................8

4.1 Mains Connection

4.2 Audio Connection

- Wiring Configuration

- In Line Connection

- Insert Points Connection

4.3 Rack Mounting

5. APPLICATION ............................................................................................. .................................10

5.1 The Sound Frequency

5.2 Equalizer In Sound Reinforcement Systems

-Line Instrument

-Mixing Console

6. TECHNICAL SPECIFICATIONS ....................................................................................................12

7. WARRANTY ........... ............................................................................................ .........................13

3

1. INTRODUCTION

Thank you very much for expressing your confidence in LTO products by purchasing our EQU Series Graphic
Equalizers. With the EQU Series you have acquired an extremely musical and flexible Graphic Equalizer.

The high-end EQU Series are based on many years of experience and are designed to provide a permanent precise
equalization to the musician, performer, studio engineer and sound contractor. The EQU Series can be used
wherever is requested to modify the frequency " contour " of a sound and can offer a solution to many common
sound problems and allows the user to use the creativity to obtain nice results in terms of sound characterization.

EQU Series Graphic Equalizers include the following seven models:

EQU131 ­EQU215 ­EQU2215 ­EQU131VU ­EQU231VU­EQU231LED ­EQU231TWIN -

Graphic Mono 31 Band Equalizer
Graphic Stereo 15 Band Equalizer

Graphic Stereo 15 Band Equalizer

Graphic Mono 31 Band Equalizer / VU Meter*1

Graphic Stereo 31 Band Equalizer / VU Meter*2

Graphic Stereo 31 Band Equalizer / LED Display*2

Graphic Stereo 31Band Equalizer /LED Display*2

2. FEATURE LIST

Easy to Operate Front Panel Controls
Constant Q circuitry with a 3% center frequency accuracy
Control range 6dB / 12dB selectable
Active balanced and unbalanced input and output connectors
Variable input level control
Signal clip pilot
Ground "LIFT" switch to disconnect signal ground from chassis ground
Power off automatic bypass function
Line voltage selectable
Robust and Compact design
Intended for installation in standard 19" rack space
Manufactured Under ISO9001 Certified management system

3. CONTROL ELEMENTS

3.1 The Front Panel

EQU131 Front Panel

R

LTO

EQU131

EQU215 Front Panel

Dual 15 Band Graphic Equalizer

R

LTO

EQU215

25 40 63 100 160 250 400 630

EQU2215 Front Panel

Dual 15 Band Graphic Equalizer

R

LTO

EQU2215

25 40 63 100 160 250 400 6301K1.6K 2.5K4K6.3K 10K 16K

1.6K 2.5K4K6.3K 10K 16K

1K

1

31 Band Graphic Equalizer

+12 +6

-12

+17

HI-PASS LOW-PASS

0dB

0

-

-6

40Hz 16 KHz

LEVEL20K16K12.5K10K8K6.3K5K4K3.15K2.5K2K1.6K1.25K1K8006305004003152502001601251008063504031.52520

1 2 3 4 576 9 8

131243131243

Channel One

Channel One

HI-PASS

LOW-PASS

+18

+12 +6

40Hz

0dB

0

-

-6

-12

BYPASS

LEVEL

2 6 8 5 7

+18

+12 +6

+14

+10

3

0

0dB

HI-PASS

LOW-PASS

-8

-12

40Hz

-

-6

-12

0

BYPASS

LEVEL

16KHz

RANGE

16KHz

RANGE

40Hz

16KHz

BY-PASS

CLIP

12

16KHz

Channel Two

12

6

25

40 63 100

250 400 630 1K 1.6K 2.5K 4K 6.3K 10K

160

1

13

Channel Two

40Hz

40 63 100

25

CLIP

250 400 630 1K 1.6K 2.5K 4K 6.3K 10K

160

RANGEBY-PASS

6

12

CLIP

HI-PASS

LOW-PASS

+18

+12 +6

40Hz

16KHz

0dB

0

-

-6

-12

BYPASS

LEVEL

RANGE

16K

2 6 8 5 7 10

+18

+12 +6

+14

+10

0

0dB

HI-PASS

LOW-PASS

-8

-12

40Hz

16KHz

-

-6

-12

BYPASS

LEVEL

RANGE

16K

40Hz

16KHz

BY-PASS

CLIP

12

40Hz

16KHz

BY-PASSBY-PASS

CLIP

ON

OFF

POWER

10

12

6

POWER

ON

OFF

13

1212

66

POWER

ON

OFF

8

1

2

5

6

7

1

2

6

7

5

10

8

4

EQU131VU Front Panel

11

R

LTO

LTO

EQU131VU

20 31.5 50 100 200 500 1.25K 2.5K 6.3K 12.5K25 40 80 160 400 1K 2K 5K 10K63 125 315 800250 630 1.6K 4K3.15K 8K 16K 20K

EQU231VU Front Panel

20 31.5 50 100 200 500 1.25K 2.5K 6.3K 12.5K25 40 80 160 400 1K 2K 5K 10K63 125 315 800250 630 1.6K 4K3.15K 8K 16K 20K

R

LTO

EQU231VU

20 31.5 50 100 200 500 1.25K 2.5K 6.3K 12.5K25 40 80 160 400 1K 2K 5K 10K63 125 315 800250 630 1.6K 4K3.15K 8K 16K 20K

EQU231LED Front Panel

20 31.5 50 100 200 500 1.25K 2.5K 6.3K 12.5K25 40 80 160 400 1K 2K 5K 10K63 125 315 800250 630 1.6K 4K3.15K 8K 16K 20K

R

LTO

EQU231LED

20 31.5 50 100 200 500 1.25K 2.5K 6.3K 12.5K25 40 80 160 400 1K 2K 5K 10K63 125 315 800250 630 1.6K 4K3.15K 8K 16K 20K

1

31 Band Graphic Equalizer

1

Dual 31 Band Graphic Equalizer

31 Band Graphic Equalizer

Channel One

Channel Two

Channel One

Channel Two

+17

+12 +6

+13

+9

0dB

0

-9

-13

-

-6

-12

LEVEL

2

LEVEL

+17

+12 +6

0dB

0

-

-6

-12

+17

+12 +6

0dB

0

-

-6

-12

LEVEL

2 11

LEVEL

+17

+12 +6

0dB

0

-

-6

-12

+17

+12 +6

0dB

0

-

-6

-12

LEVEL

POWER OUTPUT

HI-PASS

LOW-PASS

40Hz 16 KHz

31213

4 7

R

LTO

POWER OUTPUT

R

LTO

POWER OUTPUT

HI-PASS

LOW-PASS

40Hz 16 KHz

HI-PASS

LOW-PASS

40Hz 16 KHz

R

LTO

BY-PASS RANGE

6 12

CLIP

5

9 8

HI-PASS

LOW-PASS

16KHz

40Hz

BY-PASS

BYPASS

RANGE

HI-PASS

LOW-PASS

40Hz

16KHz

BY-PASS

BYPASS

RANGE

6 8 5 7 10

14

BY-PASS RANGE

6

CLIP

BY-PASS RANGE

12126

CLIP

ON

OFF

POWER

10

131243

40Hz

16KHz

12

6

CLIP

40Hz

16KHz

12

6

CLIP

POWER

POWER

ON

OFF

ON

OFF

1

2

31213

4

98

10

5

7

EQU231TWIN Front Panel

14

R

LTO

EQU231TWIN

20 31.5 50 100 200 500 1.25K 2.5K 6.3K 12.5K25 40 80 160 400 1K 2K 5K 10K63 125 315 800250 630 1.6K 4K3.15K 8K 16K 20K

Dual 31 Band Graphic Equalizer

20 31.5 50 100 200 500 1.25K 2.5K 6.3K 12.5K25 40 80 160 400 1K 2K 5K 10K63 125 315 800250 630 1.6K 4K3.15K 8K 16K 20K

Channel One

Channel Two

1

+12 +6

-12

+12 +6

-12

LEVEL

+17

+13

+9

0

0dB

HI-PASS

-9

-13

-

-6

40Hz 16 KHz

+17

+13

+9

0dB

0

-6

LEVEL

-9

-13

-

2

HI-PASS

40Hz 16 KHz

31213

BY-PASS RANGE

LOW-PASS

126

CLIP

BY-PASS RANGE

LOW-PASS

126

CLIP

5

47

98

POWER

10

ON

OFF

1. Filter level controls

Each one of these linear potentiometers will boost or attenuate (either 6dB or 12dB) the selected
frequency at a preset bandwidth.
When all the sliders are in the centre position, the output of the equalizer is flat response.

55

2. Level control

This control sets the input signal level to the equalizer. Its "0dB" position is unity gain (no boost or attenuation).
If the clip LED(5) is light continuously, turndown this control until it only flickers occasionally.

3. High pass filter

This button electronically inserts a filter into the signal path, which cuts the low frequencies at 40Hz (12dB
per octave). The LED (12) indicator lights when the button is pressed and this filter is serving in the circuit.

4. Low pass filter

This button electronically inserts a filter into the signal path, which cuts the high frequencies at 16KHz (12dB
per octave). The LED (13) indicator lights when the button is pressed and this filter is serving in the circuit.

5. Clip LED

This LED will light when any section of the equalizer is within 5 dB of clipping. Occasional flickering of
this clip LED is acceptable, but if it remains on continuously, you should turn down the level control or
reduce the output level of the preceding component to avoid audible distortion.

6. Bypass switch

This switch inserts or removes the equalizer channel path. If bypass, the bypass LED(7) will be
illuminated to indicate it is in bypass mode. When bypassed, the input signal is routed directly to the
output jacks. When power loss, the unit automatic bypassed.

7. Bypass LED

When this LED lights, it is in bypass mode.

8. Range switch

This button switches the gain range of the filter potentiometer between 6dB and 12dB.

9. Filter range indicator

When the 6dB range is selected, green LED will light. When the 12dB range is selected, red LED will
light.

10. Power switch

This is used to switch the equalizer on and off. The appliance would be turned on when the power switch
to be set to the on-position, and it would be turned off when the switch be set to the off-position.

11. VU meter

This VU meter is used to indicate the output level.

12. High pass LED

When the High pass filter(40Hz/12dB) is in active, this LED will light.

13. Low pass LED

When the Low pass filter(16KHz/12dB) is in active, this LED will light.

14. Output level meter

This output level meter is used to indicate the output level.

3.2 The Rear Panel

EQU131 Rear Panel

19

PUSH

NEW TIDE

3

21

IN

20

RISK OF FIRE-REPLACE
FUSE AS MARKED

18

LIFT
GND

MODEL

SERIAL

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a

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h

c

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A

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m

OUT

UNBALANCED

OUT

IN

IN

BALANCED

OUT

17 16 15

EQU215 Rear Panel

19

RISK OF FIRE-REPLACE
FUSE AS MARKED

20

18

Rheinland

LIFT
GND

Productioninspected

Channel Two

OUT

IN

UNBALANCED

OUT

BALANCED

OUT

PUSH

NEW TIDE

21

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3

IN

OUT

.

c

US

UNBALANCED

Channel One

IN

OUT

BALANCED

OUT

17 16 15 17 16 15

6

PUSH

NEW TIDE

3

21

IN

EQU2215 Rear Panel

19

RISK OF FIRE-REPLACE
FUSE AS MARKED

MODEL

SERIAL

LIFT
GND

OUT

IN

UNBALANCED

Channel Two

OUT

Rheinland

Productioninspected

IN

BALANCED

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a

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m

OUT

PUSH

NEW TIDE

3

21

IN

Channel One

IN

OUT

UNBALANCED

OUT

IN

BALANCED

OUT

PUSH

NEW TIDE

3

21

IN

20

18 17 16 1517 16 15

EQU131VU Rear Panel

19

RISK OF FIRE-REPLACE
FUSE AS MARKED

LIFT
GND

20

EQU231LEDEQU231VU/ Rear Panel

19

20

EQU231TWIN Rear Panel

19

18

RISK OF FIRE-REPLACE
FUSE AS MARKED

18

LIFT
GND

MODEL

SERIAL

MODEL

SERIAL

Rheinland

Rheinland

C

Productioninspected

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OUT

UNBALANCED

OUT

IN

IN

BALANCED

OUT

NEW TIDE

3

21

IN

17 16 15

PUSH

Channel One

OUT

UNBALANCED

Productioninspected

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OUT

UNBALANCED

IN

Channel Two

IN

OUT

OUT

IN

BALANCED

IN

BALANCED

OUT

OUT

PUSH

NEW TIDE

3

21

IN

PUSH

NEW TIDE

3

21

IN

17 16 15

Channel One

20

RISK OF FIRE-REPLACE
FUSE AS MARKED

18

LIFT
GND

MODEL

SERIAL

OUT

UNBALANCED

OUT

UNBALANCED

17 16 15

IN

Channel Two

Channel Two

IN

OUT

OUT

IN

BALANCED

IN

BALANCED

OUT

OUT

15. XLR input and output connector

The XLR connector are actively balanced and are used to input/output the signal.

16. 1/4" TRS phone plug input and output connector

The 1/4" TRS connector are actively balanced and are used to input/output the signal.

17. RCA input and output connector

The RCA connector are unbalanced.

7

PUSH

NEW TIDE

3

21

IN

PUSH

NEW TIDE

3

21

IN

NOTE : While you can use any input connector with any output connector, only one set of these con­nectors is to be used at one time, detail wiring and connection, please refer to 4.2 audio connection.

18. Ground lift switch

This switch is used to disconnect the signal ground from the mains and chassis earth. If it is determined
that the equalizer is the cause of hum or buzz in your system due to a ground loop, move this switch to the
"lift" position.

19. Fuse holder / Voltage selector

This is a dual voltage unit. Before you attempt to connect and operate the unit, please make sure that your
local voltage matches the voltage on the fuse-holder cover.

Caution: The fuse protecting the AC supplies circuits of this unit. The fuse can only be changed by
a qualified technician, in the event of a fault or changing the supply voltage. If the fuse continues to
blow after replacing, discontinue use of this unit before repaired.

110-120V

220-240V

220-240V

110-120V

THIS IS SET FOR
110V AC TO 120V

AC OPERATION

The fuse-holder above the AC connector on the rear of the chassis has 3 triangular markers(please
refer to the above pictures), with two of these triangles opposing each other, your unit is set to the
operating voltage printed next to these markers.

To change, pull fuse-holder out and rotate 180 ,then push in again.

20. AC Inlet

This connector is meant for the connection of the supplied main cord.
Do not insert power cable into unit until voltage has been correctly set. Do not plug power cable into AC
power until voltage has been correctly set.

4. INSTALLATION & CONNECTION

4.1 Mains Connection

Please ensure that the EQU Series Graphic Equalizer is set to the correct supply voltage before plugging
the power cord into the wall outlet , use the same fuse as marked on the fuse holder at the AC power
connection socket.

The mains connection of the is made by using the enclosed mains cable and
a standard IEC receptacle. It meets all of the international safety certification requirements.

4.2 Audio Connection

The presents with balanced XLR & 1/4" TRS and unbalanced RCA connectors,EQU Series Graphic Equalizer
and it can be interfaced by several ways to support a variety of applications without any signal loss. The
EQU Series Graphic Equalizer can be used on a single instrument by connecting to a mixing console's main
inserts, or on an entire mix "in-line" between a mixing console's outputs and a power amplifier.

- Wiring Configuration

Either the 1/4" TRS phone jack or the XLR connector can be wired in balanced and unbalanced modes, which
will be determined by the actual application status, please wire your system as the following wiring examples:

EQU Series Graphic Equalizer

THIS IS SET FOR
220V AC TO 240V

AC OPERATION

1/4"TRS jack

Unbalanced Input

1/4"TRS jack

Balanced Input

XLR Balanced InputXLR Unbalanced Input

8

- In Line Connection

For these applications the provides 1/4" TRS connectors, XLR connectorsEQU Series Graphic Equalizer
and RCA connectors to easily interface with most any professional audio device. Follow the configuration
examples below for your particular connection.

Balanced

TIPRING SLEEVE

TIPRING SLEEVE

Unbalanced

TIPRING SLEEVE

TIPSLEEVE

TIPSLEEVE

TIPRING SLEEVE

TIPSLEEVE

TIPRING SLEEVE

SLEEVERING TIP

SLEEVETIP

SLEEVERING TIP

Tip

Ring

Sleeve

Tip

Ring

Sleeve

Tip

Ring

Sleeve

Tip

Sleeve

Tip

Sleeve

Tip

Ring

Sleeve

Tip

Sleeve

Tip

Ring

Sleeve

Tip
Ring

1
2

3

1
2
3

1
2

3

Sleeve

1
2

3

1
2
3

1
2
3

1
2
3

Centre

Screen

Tip

Sleeve

Tip
Ring

Sleeve

Centre
Screen

Centre

Screen

1
2

3

- Insert Points Connection

If you are connecting to a mixing console's main inserts, you may have a single TRS jack for SEND &
RETURN, in this case, use an insert "Y" cable that configured like the examples below.

1/4" TRS insert

Insert Leads

TIPRING SLEEVE

TIPRING SLEEVE

TIPRING SLEEVE

SLEEVETIP

SLEEVETIP

Ring

Sleeve

Ring

Sleeve

Ring

Sleeve

Tip

Tip

Tip

4.3. Rack Mounting

The most secure mounting is on a universal rack shelf available from various rack manufactures or your
music dealer. The EQU Series fits into one standard 19" rack unit of space, but the EQU131 and EQU215
will be 1H height, the EQU231TWIN will be 4H height, while the other four models: EQU2215, EQU131VU,
EQU231VU and EQU231LED will be 2H height. Please allow at least an additional 4" depth for the connectors
on the rear panel. Be sure that there is enough air space around the unit for sufficient ventilation and please
do not place the on high temperature devices such as power amplifiers etc. to avoid overheating.EQU Series

Tip (Send)
Sleeve

Tip (Return)
Sleeve

1
2(Send)
3

1
2(Return)
3

Centre(Send)
Screen

Centre(Return)
Screen

9

5. APPLICATION

5.1 The Sound Frequency

In recording studios as well as stage or radio plays, the EQU Series Graphic Equalizer will be your
valuable sound tool to modify the frequency "contour " of a sound .but first of all , you should clearify the

typical frequency of each instrument and voice, so that can you obtain nice results in terms of sound
characterization. The tables on the following pages give you an idea of specific frequencies and their
acoustic significance.

Typical Frequency of Each Instrument and Voice

CDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABCDEFGABC

25 31 4 0 50 6 2 8 0 10 0 125 1 60 20 0 250 32 0 400 5 00 64 0 800 1K 1 .3K 1.6 K 2K 2.5K 3.1K 4 K 5 K 6. 2K 8K 10 K 13 K 16 K 20 K

25 31 40 50 6280100 125 160 200 250 320 400 500 640

Mid C

800

1.3K1.6K2K2.5K 3.1K

1K

5K

6.2K8K10K 13K 16K 20K

4K

Hyman gearing
range VOCAL

Soprano

Contralto

Baritone

Bass

WOODWIND

Piccolo

Flute

Oboe

Clarinet in B flat or A

Clarinet in E flat

Bass Clarinet

Basset Hom

Cor Anglais

Bassoon

Double Bassoon

BRASS

Soprano Saxophone

Alto Saxophone

Tenor Saxophone

Baritone Saxophone

Bass Saxophone

Trumpet in C

Trumpet in F

Alto Trombone

Tenor Trombone

Bass Trombone

Tuba

Valve Hom

STRINGS

Violin

Viola

Cello

Double Bass

Guitar

KEYBOARDS

Pianoforte

Organ

PERCUSSION

Celesta

Timpani

Xylophone

FREQUENCY

10

5.2 Equalizer In Sound Reinforcement Systems

The EQU Series Graphic Equalizers can be used in the sound reinforcement systems to :

Eliminate unwanted sounds, such as the 60Hz Hum noise.
Shape the sound by changing the frequency response of the track.
Special effects like telephone sounds are done by cutting off the low end to 200Hz and the high end

to 6KHz.

Allow you to modify the sound of the instrument if put EQU Series Equalizer in line with a musical

instrument. you can brighten the sound, and body to a thin sounding instrument, or you can give the
sound a totally different character.

Fix a track that does not sound quite right, put the EQU Series Equalizer in an effects send and return

it to the mix bus.

The following connection is probably most common field of application:

- Line Instrument

The EQU Series Graphic Equalizer can be used on an entire mix "In-line" between a instrument outputs
and a power amplifier, and this is the basic application in the PA system to offer precise Equalization
control.

CH1 IN

CH2 IN

CH1 OUT

CH2 OUT

From line instrument
outputs

20 31.5 50 100 200 500 1.25K 2.5K 6.3K 12.5K25 40 80 160 400 1K 2K 5K 10K63 125 315 800250 630 1.6K 4K3.15K 8K 16K 20K

R

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EQU231LED

20 31.5 50 100 200 500 1.25K 2.5K 6.3K 12.5K25 40 80 160 400 1K 2K 5K 10K63 125 315 800250 630 1.6K 4K3.15K 8K 16K 20K

Dual31 Band Graphic Equalizer

To power amplifier inputs

LEVEL

+17

ChannelOne

ChannelTwo

+12+6

0

-6

-12

+12+6

0

-6

-12

BY-PASS RANGE

HI-PASS

LOW-PASS

0dB

-

+17

0dB

-

LEVEL

40Hz 16KHz

HI-PASS

40Hz 16KHz

6

CLIP

BY-PASS RANGE

LOW-PASS

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CLIP

POWER

ON

OFF

- Mixing Console

The EQU Series Graphic Equalizer can also be used on a single instrument by connecting to a mixing
console's main inserts, esp for those consoles without built-in equalization circuitry.

Main Inserts

MIXING CONSOLE

20 31.5 50 100 200 500 1.25K 2.5K 6.3K 12.5K25 40 80 160 400 1K 2K 5K 10K63 125 315 800250 630 1.6K 4K3.15K 8K 16K 20K

R

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EQU231LED

20 31.5 50 100 200 500 1.25K 2.5K 6.3K 12.5K25 40 80 160 400 1K 2K 5K 10K63 125 315 800250 630 1.6K 4K3.15K 8K 16K 20K

CH1 IN

Dual31 Band Graphic Equalizer

CH1 OUT

CH2 IN

ChannelOne

ChannelTwo

CH2 OUT

LEVEL

+17

+12+6

HI-PASS

0dB

0

-

-6

-12

40Hz 16KHz

+17

+12+6

HI-PASS

0dB

0

-

-6

-12

40Hz 16KHz

LEVEL

BY-PASS RANGE

LOW-PASS

6

CLIP

BY-PASS RANGE

LOW-PASS

CLIP

ON

OFF

12126

POWER

NOTE: Mono/Stereo Application

a. For mono application, please use the EQU131, EQU131VU mono Graphic Equalizer.
b. For stereo application, please use the EQU215, EQU2215, EQU231LED, EQU231VU or

EQU231TWIN stereo Graphic Equalizer, either of the two channels can be used as L/R input
& output.

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6. TECHNICAL SPECIFICATIONS

Type

E

QU131

EQU215
EQU2215
EQU131VU
EQU231VU / 231LED
EQU231TWIN

1 31 Band: 1/3 octave , ISO spacing (1H series)
2 15 Band: 2/3 octave , ISO spacing (1H series)
2 15 Band: 2/3 octave , ISO spacing (2H series)
1 31 Band: 1/3 octave , ISO spacing (2H series)
2 31 Band: 1/3 octave , ISO spacing (2H series)
2 31 Band: 1/3 octave , ISO spacing (4H series)

Slider travel

Range

Input connections

Input impedance

Maximum input level

Output connections

Output impedance

Maximum output level

Load impedance

High pass filter

Low pass filter

Frequency response

THD+N%

S/Nratio

Power supply

Consumption

EQU131/131VU
EQU215/2215
EQU231VU / 231LED/231TWIN

20mm with positive centre detente
(EQU131/EQU215/EQU231VU/EQU231LED)
60mm with positive centre detente
(EQU131VU/EQU2215/EQU231TWIN)

6dB or 12dB selectable

Active balanced XLR and 1/4" TRS
Unbalanced RCA

20k (bal.)
15k (unbal.)

18dBv

Active balanced XLR and 1/4" TRS
Unbalanced RCA

600

16dBv

>10K

40Hz (12dB/oct) fixed-button type .

16KHz (12dB/oct) fixed-button type

20Hz to 50KHz at - 3dB

0.02% (@ 1KHz , all VR at middle position)

93dB (@ 1KHz )

110V-120VAC -60Hz
220V-240VAC -50Hz

1 31 band, 1/3 octave, ISO spacing: 7W
2 15 band, 2/3 octave, ISO spacing: 9W
2 31 band, 1/3 octave, ISO spacing: 12.5W

Dimensions

483(W) 220(D) 44(H)(19" 8.66" 1.7")mm (1H series)

483(W) 220(D) 88(H)(19" 8.66" 3.5") mm (2H series)

483(W) 220(D) 177.8(H)(19" 8.66" 7") mm (4H series)

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7. WARRANTY

1. WARRANTY REGISTRATION CARD

To obtain Warranty Service, the buyer should first fill out and return the enclosed Warranty Registration
Card within 10 days of the Purchase Date.
All the information presented in this Warranty Registration Card gives the manufacturer a better under­standing of the sales status, so as to purport a more effective and efficient after-sales warranty service.
Please fill out all the information carefully and genuinely, miswriting or absence of this card will void your
warranty service.

2. RETURN NOTICE

2.1 In case of return for any warranty service, please make sure that the product is well packed in its original
shipping carton, and it can protect your unit from any other extra damage.

2.2 Please provide a copy of your sales receipt or other proof of purchase with the returned machine ,and
give detail information about your return address and contact telephone number .

2.3 A brief description of the defect will be appreciated.

2.4 Please prepay all the costs involved in the return shipping, handling and insurance.

3. TERMS AND CONDITIONS

3.1 warrants that this product will be free from any defects in materials and/or workmanship for

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a period of 1 year from the purchase date if you have completed the Warranty Registration Card in
time.

3.2 The warranty service is only available to the original consumer, who purchased this product directly
from the retail dealer, and it can not be transferred.

3.3 During the warranty service, may repair or replace this product at its own option at no charge to

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you for parts or for labor in accordance with the right side of this limited warranty.

3.4 This warranty does not apply to the damages to this product that occurred as the following conditions:

Instead of operating in accordance with the user's manual thoroughly, any abuse or misuse of this
product.

Normal tear and wear.

The product has been altered or modified in any way.

Damage which may have been caused either directly or indirectly by another product / force / etc

Abnormal service or repairing by anyone other than the qualified personnel or technician.

And in such cases, all the expenses will be charged to the buyer.

3.5 In no event shall be liable for any incidental or consequential damages. Some states do not allow

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the exclusion or limitation of incidental or consequential damages, so the above exclusion or limitation
may not apply to you.

3.6 This warranty gives you the specific rights, and these rights are compatible with the state laws, you
may also have other statutory rights that may vary from state to state.

13