HZA4-120F

AMPLIFIERS
Flexi-power Amplifier

USER MANUAL

50-0241-0105 HZA4-120F EN
INDEX
IMPORTANT REMARK............................................................................................................. 3

IMPORTANT SAFETY INSTRUCTIONS ............................................................................... 4

IMPORTANT NOTE................................................................................................................... 5

INTRODUCTION ........................................................................................................................ 5

4.1. Main Features ............................................................................................................................. 5

INSTALLATION.......................................................................................................................... 6

5.1. Placement and mounting......................................................................................................... 6

5.2. Mains connection ........................................................................................................................ 6
5.3. Signal input connections .......................................................................................................... 7
5.4. Output connections and channel linking with the FLEXIPOWER function ............. 8
5.5. Internal switches for high-pass filters................................................................................. 9
5.6. Remote control ports for attenuation .................................................................................. 9
5.7. REMOTE CONTROL ports connection ................................................................................ 9
OPERATION AND USAGE ....................................................................................................10

6.1. Start up ........................................................................................................................................ 10

6.2. Front panel LED indicators .................................................................................................... 10
6.3. Front panel volume controls................................................................................................. 11
6.4. AUTO STBY ON/OFF switch ................................................................................................ 11
CLEANING .................................................................................................................................11

CONTROL PANEL FUNCTIONS ..........................................................................................12

8.1. Front Panel ................................................................................................................................. 12

8.2. Rear Panel .................................................................................................................................. 13
DIAGRAMS ...............................................................................................................................14

9.1. Configuration Diagram ........................................................................................................... 14

9.2. Block Diagram ........................................................................................................................... 14
TECHNICAL CHARACTERISTICS .......................................................................................15

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 IMPORTANT REMARK

The lightning flash with arrowhead symbol, within an equilateral triangle, is

intended to alert the user to the presence of uninsulated “dangerous voltage”
within the product’s enclosure that may be of sufficient magnitude to
constitute a risk of electric shock to persons.

The exclamation point within an equilateral triangle is intended to alert the

user to the presence of important operating and maintenance (servicing)
instructions in the literature accompanying the appliance.

WARNING (If applicable): The terminals marked with symbol of “ ” may be of

sufficient magnitude to constitute a risk of electric shock. The external wiring connected
to the terminals requires installation by an instructed person or the use of ready-made
leads or cords.

WARNING: To prevent fire or shock hazard, do not expose this equipment to rain or
moisture.

WARNING: An apparatus with Class I construction shall be connected to a mains

socket-outlet with a protective earthing connection.

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 IMPORTANT SAFETY INSTRUCTIONS

1. Read these instructions.

2. Keep these instructions.
3. Heed all warnings.
4. Follow all instructions.
5. Do not use this apparatus near water.
6. Clean only with dry cloth.
7. Do not block any ventilation openings. Install in accordance with the
manufacturer’s instructions.
8. Do not install near any heat sources such as radiators, heat registers, stoves, or
other apparatus (including amplifiers) that produce heat.

9. 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.
10. Protect the power cord from being walked on or pinched particularly at the plugs,
convenience receptacles, and at the point where they exit from the apparatus.
11. Only use attachments/accessories specified by the manufacturer.
12. Unplug the apparatus during lightening sorts or when unused for long periods of
time.
13. Refer all servicing to qualified personnel. 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.
14. Disconnecting from mains: When switching off the POWER switch, all the
functions and light indicators of the unit will be stopped, but fully disconnecting
the device from mains is done by unplugging the power cable from the mains
input socket. For this reason, it always shall remain easily accessible.
15. Equipment is connected to a socket-outlet with earthing connection by means of
a power cord.
16. The marking information is located at the bottom of the unit.
17. The apparatus shall not be exposed to dripping or splashing and that no objects
filled with liquids, such as vases, shall be placed on apparatus.

WARNING: This product must not be discarded, under any circumstance, as

unsorted urban waste. Take to the nearest electrical and electronic waste
treatment centre.

NEEC AUDIO BARCELONA, S.L. accepts no liability for any damage that may be caused
to people, animal or objects due to failure to comply with the warnings above.

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 IMPORTANT NOTE

Thank you for choosing our Ecler HZA4-120F Flexi-power Amplifier!

It is VERY IMPORTANT to carefully read this manual and to fully understand its
contents before any connection in order to maximize your use and get the best
performance from this equipment.

To ensure optimal operation of this device, we strongly recommend that its maintenance
be carried out by our authorised Technical Services.

Ecler HZA4-120F comes with a 3-year warranty.

INTRODUCTION

The HZA4-120F is a four-channel power amplifier with high impedance (100V line)
directly amplified outputs.

4.1. Main Features

• Internal structure with four separate mono amplifiers, for 4 different mono input
signals.
• The FLEXIPOWER technology can be used to link 2, 3 or 4 adjacent channels,
adding their individual power, while operating as a single amplifier channel with a
total power equivalent to the sum of the channels.
• Independent volume adjustment (per channel) through front panel controls.
• Independent (per channel) 0-10 VDC remote volume control, via screw terminals
on rear panel.
• SPM 100 Technology - Channel N for direct high impedance amplification (100V
line) without output transformers, which has the following benefits compared to
traditional 100V line amplification with transformers:
o Better frequency response in the low band of the audible spectrum (low
frequencies or bass) because there is no degradation of this part of the
spectrum usually due to the saturation of transformers core.
o Great efficiency.
o Reduced weight.
• Convection cooling, without fan, with the following benefits:
o No background noise.
o Increased reliability.
• “Auto-standby” function: the amplifier automatically switches to standby mode
(low consumption mode) when it remains approximately two minutes without
detecting any input signal, then immediately switches back to normal operating
mode when an input signal is re-detected.
• Thermal protection.
• Overload protection.
• “Anticlip” system to protect from saturation due to an excessively high signal level.
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 INSTALLATION

5.1. Placement and mounting

The amplifier is presented as a 2 unit high 19'' rack module. It is supplied with plastic
washers in order not to damage the unit when tightening the screws.

Remark: It is very important that the amplifier is not completely enclosed, covered,
or exposed to extreme temperatures, as the amplifier, itself, generates heat. Proper
ventilation is necessary, allowing air to pass through the ventilation holes of the
chassis. Leaving at least one rack unit free between each device and those installed
above and below it in the rack frame is recommended.

If the setup has several amplifiers in the same rack or in a closed cabinet with doors, it is
highly recommended to supply them forced ventilation, installing fans at the upper and
lower ends. This upward air flow will help to dissipate the heat generated inside.

In order to optimize as much as possible, the correct thermal dissipation of equipment

installed in a closed rack, it is advisable not to place power amplifiers under other
appliances, but upon these ones.

5.2. Mains connection

The HZA4-120F amplifiers are fed with alternate currents, depending on the country, of
110-120, 220-240V 47-63Hz. (see characteristics in the back of the unit).

The amplifier should have an earth connection in good conditions (earth resistance,
Rg=30 or less). The environment must be dry and dustless. Do not expose the unit to
rain or water splashes, and do not place liquid containers or incandescent objects like
candles on top of the unit. Do not obstruct the ventilation grids with any kind of material.

In case there is some type of intervention and/or connection-disconnection of the

amplifier, it is most important to previously disconnect the mains power supply. There
are no user or serviceable parts inside the amplifier.

You should avoid that the supply cable twists with the shielded signal cables, as this
could lead to unwanted hum.

In order to protect the unit from an eventual electrical overload or momentary power
peaks from the internal circuits it carries a fuse. Should it ever blow up, unplug the unit
from mains and replace it with an identical one. If the new fuse blows again contact
immediately with our Authorized Technical Service.

CAUTION: YOU MUST NEVER USE A HIGHER VALUE FUSE.

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5.3. Signal input connections

The amplifier HZA4-120F features 4 balanced and line level analog signal inputs (one
per amplification channel) on its rear panel.

Signal input connectors are 3 position screw terminal block (40, 41, 43, 45). The wiring
is:

HOT or direct signal > Pin +

COLD or inverted signal > Pin -
GROUND > Pin ⊥

For unbalanced connection short-circuit pin ⊥ to pin -.

TACK outputs (42, 44) available for inputs 1 and 2 are parallel to the input and serve to
re-send the signal of these inputs (INPUTS, CH1 / CH2) to other input channels,
amplifiers or sound systems.

The input impedance is 20K (balanced) with a nominal input sensitivity of 0dBV(1V).
This impedance makes possible to parallel several amplifiers without losing audio
quality.

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 5.4. Output connections and channel linking with the FLEXIPOWER function

The rear panel OUTPUTS section is fitted with two position screw terminal block (28, 29,
30, 31) for each amplifier channel. Always respect the relative polarity for outputs (0 and
100 on each output connector), wiring and speakers.

The FLEXIPOWER Function: a MERGE switch is installed between each pair of output
connectors:

• When the switch is in the top position, the pair of channels has an independent
behaviour; the FLEXIPOWER function will not be active

• When the switch is in the lower position (MERGE), the two channels will be linked
and their individual power will be added:

o The two outputs of the pair of channels and the speaker lines connected
to these channels will be connected in parallel

o The MERGE LED (6, 11, 16) light on the front panel, between the pair of
channels, will be lit

o The audio content of the pair of channels becomes the sound source
connected to the input of the channel with a lower number (input 1 for
channel pair 1&2, input 2 for channel pair 2&3, input 3 for channel pair
3&4)

o The active front and remote volume control (if used) of the channel pair
becomes that of the channel with a lower number (controls on channel 1
for channel pair 1&2, controls on channel 2 for channel pair 2&3, controls
on channel 3 for channel pair 3&4)

PRECAUTION: DO NOT MANIPULATE THE “MERGE” SWITCHES WHEN

THE AMPLIFIER IS SWITCHED ON

2, 3 or 4 adjacent channels can be linked (with a resulting double, triple or quadruple

power), with the following sound source and volume control arrangement:

FLEXIPOWER inputs routing and associated volume controls

MERGED CHANNELS
Independent 1&2 2&3 3&4 1&2&3 2&3&4 1&2&3&4
CHANNEL 1 IN 1 IN1 IN1 IN1
IN1
CHANNEL 2 IN 2 IN2 IN1
IN2 IN1
CHANNEL 3 IN 3 IN3 IN2
IN3
CHANNEL 4 IN 4 IN4 IN4 IN4

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5.5. Internal switches for high-pass filters

Inside the amplifier there are four jumpers to activate/deactivate the high-pass filter for
each amplifier channel, with a cutoff frequency set at 70Hz and a slope of 18dB/octave.
The high-pass filter is recommanded for some 100V line applications, especially when
audio content is primarily vocal (public address announcements, for example). See
section 9.1. Configuration Diagram for more information.

5.6. Remote control ports for attenuation

The HZA4-120F features 4 remote control ports labeled “REMOTE CONTROL” (35, 36,
37, 38) on its rear panel. You can connect WPm series, REVO control panels etc. to each
of these ports to remotely attenuate the input signal (and therefore, the output volume
of affected channels).

The maximum level of each amplification channel (and therefore its output volume) that
can be reached by the remote attenuator is determined by the position of its front knob
(21, 22, 23, 24).

5.7. REMOTE CONTROL ports connection

The signal remote attenuation level for each input channel can be set by using 3 types of
external devices connected to the rear panel REMOTE CONTROL ports:

a) Using a remote potentiometer

with nominal resistance
between 10k and 50k, WPm
series or equivalent.

b) Using a device that generates a

control voltage from 0 to 10V
DC.

c) Using remote relays/dry contacts.

Remark: you can connect up to 16 REMOTE CONTROL ports in parallel to the same
hardware control potentiometer. You have to merge the ground of all amplifiers
belonging to these ports.

The connection cables can be up to 500m long if a section of 0.5mm2 is used.

Consult the available accessories at your ECLER dealer or at www.ecler.com.

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 OPERATION AND USAGE

6.1. Start up

This will be done through the POWER ON (25) switch and the built-in indicator
immediately lights.

In a complete audio installation, it is important to start up the equipment in the following

sequence: sound sources, mixer, equalizers, active filters, processors and finally power
amplifiers. To turn them off the sequence should follow an inverse pattern.

6.2. Front panel LED indicators

The HZA4-120F is equipped with the following front panel LEDs:

• STBY indicator (1): illuminates when the amplifier is in standby (low consumption
mode), after approximately two minutes without any input signal detected. When
an input signal is re-detected, the amplifier automatically switches back to normal
operating mode.

• Signal Presence indicators, SP (2, 7, 12, 17): warn of the presence of signal at the
amplifier inputs. These indicators illuminate when the input signal exceeds -35dB.

• Overload indicators, OVL (3, 8, 13, 18): illuminate when the channel reaches its
maximum power capacity, due to a too low load impedance.

• CLIP indicators (4, 9, 14, 19): illuminate when the speakers output signal is close
to the actual clipping level. The CLIP system takes into account possible
fluctuations in the supply voltage if they exist, always giving a real indication. It is
normal when you work at high power levels that CLIP indicators illuminate to the
beat of the low frequencies, which are those with the higher energy content. Make
sure this doesn’t permanently illuminate indicators during normal operating mode.

• Thermal protection indicators, TH (5, 10, 15, 20): indicate that the channel over-
temperature protection has been activated; normal operation will be restored when
the temperature returns to the correct operating temperature range.

• MERGE Indicators: they indicate whether the FLEXIPOWER function that links two
adjacent channels have been activated with the switches on the rear panel or not.

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6.3. Front panel volume controls

The front panel features four volume knobs, one per channel, allowing independent
adjustment of the maximum output level for each amplifier channel.

Remote control ports also allow to adjust the volume of each amplifier channel from a
WPm series panel, a potentiometer or other external hardware device; the actual volume
of each channel is the result of the two volume controls position (front panel and remote
control).

In the device packaging, you’ll find a bag with clear caps to be inserted on the front panel
knobs. They protect the input attenuation settings from unsolicited tampering. Once
inserted, you must use a flathead screwdriver or a similar tool to remove them.

6.4. AUTO STBY ON/OFF switch

Switch (39) that enables/disables the auto standby mode (sleep or low consumption
mode). If this function is activated, the amplifier will switch to standby after
approximately two minutes without any input signal detected. When an input signal is
re-detected, the amplifier automatically switches back to normal operating mode.

CLEANING

The front panel should not be cleaned with dissolvent or abrasive substances because
silk-printing could be damaged. To clean it, use a soft cloth slightly wet with water and
neutral liquid soap; dry it with a clean cloth. Be careful that water never gets into the
amplifier through the holes of the front panel.

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 CONTROL PANEL FUNCTIONS

8.1. Front Panel

1 Automatic power off indicator, STBY 14 Clip indication, CLIP CH 3

2 Signal presence, SP CH 1 15 Thermal protection indicator, TH CH 3
3 Overload indicator, OVL CH 1 16 Merge indicator, MERGE 3 & 4
4 Clip indication, CLIP CH 1 17 Signal presence, SP CH 4
5 Thermal protection indicator, TH CH 1 18 Overload indicator, OVL CH 4
6 Merge indicator, MERGE 1 & 2 19 Clip indication, CLIP CH 4
7 Signal presence, SP CH 2 20 Thermal protection indicator, TH CH 4
8 Overload indicator, OVL CH 2 21 Volume, CH 1
9 Clip indication, CLIP CH 2 22 Volume, CH 2
10 Thermal protection indicator, TH CH 2 23 Volume, CH 3
11 Merge indicator, MERGE 2 & 3 24 Volume, CH 4
12 Signal presence, SP CH 3 25 Power switch and pilot light, POWER
13 Overload indicator, OVL CH 3

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8.2. Rear Panel

26 Mains socket 37 Screwable terminal for remote

27 Fuse holder control, CH 2

28 Output terminals channel 4, CH 4 38 Screwable terminal for remote

control, CH 1
29 Output terminals channel 3, CH 3
39 Standby mode selector, AUTO
30 Output terminals channel 2, CH 2
STBY
31 Output terminals channel 1, CH 1
40 Input terminals channel 4, CH 4
32 MERGE switch 3 & 4
41 Input terminals channel 3, CH 3
33 MERGE switch 2 & 3
42 Output terminals to other
34 MERGE switch 1 & 2
amplifiers, STACK CH 2
35 Screwable terminal for remote
43 Input terminals channel 2, CH 2
control, CH 4
44 Output terminals to other
36 Screwable terminal for remote
amplifiers, STACK CH 1
control, CH 3
45 Input terminals channel 1, CH 1

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 DIAGRAMS

9.1. Configuration Diagram

FACTORY ADJUST
High Pass Filter ON

on
off

9.2. Block Diagram

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 TECHNICAL CHARACTERISTICS

HZA4-120F
Output power @ 1% THD
1 Channel 114 WRMS @ 100V line
2 Merged Channels 195 WRMS @ 100V line
4 Merged Channels 290 WRMS @ 100V line
4 Merged Channels 356 WRMS @ 100V line
Output power @ 10% THD
1 Channel 145 WRMS @ 100V line
2 Merged Channels 226 WRMS @ 100V line
4 Merged Channels 348 WRMS @ 100V line
4 Merged Channels 430 WRMS @ 100V line
Others
Frequency response (-3dB) 30Hz - 55kHz
High pass filter 3rd order Butterworth 70Hz
THD+Noise @ 1kHz Full Power <0.03% typ. 0.2% max.
Signal Noise Ratio @ 100V >90dB
Channel Crosstalk @ 1kHz/100V >90dB
Inputs
Sensitivity nom / Impedance 0dBV/>20kW
Connectors Terminal Block (Symmetrical)
Outputs
Connectors Terminal Block
Indicators
Power Green (ON), Red (Standby)
Signal Present /Clip/Overload/Thermal -35dB / Yes / Yes /Yes
Remote control
DC 0-10V/0.1A max
No attenuation 0V
Full attenuation +10V
Connectors Terminal block
Auto power
Threshold >-30dB aprox
Time 100 sec. aprox
Mains voltage 115V/230V. Voltage changed internally (NOT BY SWITCH)
Power consumption
pink noise, 1/8 power @ 136Ω 340VA
pink noise, 1/3 power @ 136Ω 470VA
Standby <3W
Dimensions
Dimensions WxHxD: 482.6 x 88 x 392mm (Handle excluded)
Weight 13.60kg

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All product characteristics are subject to variation due to production tolerances.
NEEC AUDIO BARCELONA S.L. reserves the right to make changes or improvements in the design or
manufacturing that may affect these product specifications.

For technical queries contact your supplier, distributor or complete the contact form on our website,
in Support / Technical requests.

Motors, 166‐168 08038 Barcelona ‐ Spain ‐ (+34) 932238403 | information@ecler.com | www.ecler.com

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