thomann Limit 2/2 User Manual

Limit 2/2

limiter

user manual

Musikhaus Thomann
Thomann GmbH
Hans-Thomann-Straße 1
96138 Burgebrach
Germany
Telephone: [phone]
E-mail: [e-mail]
Internet: www.thomann.de

07.12.2015, ID: 288549

Table of contents

1 General notes............................................................................................................................................... 4

2 Safety instructions..................................................................................................................................... 6

3 Features....................................................................................................................................................... 10

4 Installation.................................................................................................................................................. 11

5 Starting up.................................................................................................................................................. 14

6 Connections and operating elements........................................................................................... 15

7 Technical specifications....................................................................................................................... 20

8 Cleaning....................................................................................................................................................... 22

9 Protecting the environment.............................................................................................................. 23

Table of contents

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1 General notes

This user manual contains important information on safe operation of the device. Read and
follow all safety notes and all instructions. Save this manual for future reference. Make sure
that it is available to all persons using this device. If you sell the device, include the manual for
the next owner.

Our products are subject to a process of continuous development. We therefore reserve the
right to make changes without notice.

This section provides an overview of the symbols and signal words used in this user manual.

Signal word Meaning
DANGER! This combination of symbol and signal word indicates an

immediate dangerous situation that will result in death or
serious injury if it is not avoided.

NOTICE! This combination of symbol and signal word indicates a pos‐

sible dangerous situation that can result in material and
environmental damage if it is not avoided.

Symbols and signal words

General notes

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Warning signs Type of danger

Warning – high-voltage.

Warning – danger zone.

General notes

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2 Safety instructions

This device is intended to be used to limit the dynamics of signals from audio devices and
musical instruments. Use the device only as described in this user manual. Any other use or use
under other operating conditions is considered to be improper and may result in personal
injury or property damage. No liability will be assumed for damages resulting from improper
use.

This device may be used only by persons with sufficient physical, sensorial, and intellectual
abilities and having corresponding knowledge and experience. Other persons may use this
device only if they are supervised or instructed by a person who is responsible for their safety.

Intended use

Safety instructions

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DANGER!
Danger for children

Ensure that plastic bags, packaging, etc. are disposed of properly and are not
within reach of babies and young children. Choking hazard!

Ensure that children do not detach any small parts (e.g. knobs or the like) from
the unit. They could swallow the pieces and choke!

Never let children unattended use electrical devices.

DANGER!
Electric shock caused by high voltages inside

Within the device there are areas where high voltages may be present. Never
remove any covers.

There are no user-serviceable parts inside.

Safety

Safety instructions

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DANGER!
Electric shock caused by short-circuit

Always use proper ready-made insulated mains cabling (power cord) with a pro‐
tective contact plug. Do not modify the mains cable or the plug. Failure to do so
could result in electric shock/death or fire. If in doubt, seek advice from a regis‐
tered electrician.

NOTICE!
Risk of fire

Do not cover the device nor any ventilation slots. Do not place the device near
any direct heat source. Keep the device away from naked flames.

Safety instructions

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NOTICE!
Operating conditions

This device has been designed for indoor use only. To prevent damage, never
expose the device to any liquid or moisture. Avoid direct sunlight, heavy dirt, and
strong vibrations.

NOTICE!
Power supply

Before connecting the device, ensure that the input voltage (AC outlet) matches
the voltage rating of the device and that the AC outlet is protected by a residual
current circuit breaker. Failure to do so could result in damage to the device and
possibly injure the user.

Unplug the device before electrical storms occur and when it is unused for long
periods of time to reduce the risk of electric shock or fire.

Safety instructions

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3 Features

The limiter is ideal to protect sensitive amplifier inputs against overloading. The digital signal
processors reduce the dynamics of the input signal by an adjustable value. Both stereo chan‐
nels are processed interdependently and compressed by the same ratio. The channel with the
higher dynamic controls both channels.

Special features of the device:

n Fixed values for attack and release time
n A/D and D/A converters with high resolution
n High sampling rate
n Adjustable threshold

Features

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4 Installation

Unpack and carefully check that there is no transportation damage before using the unit. Keep
the equipment packaging. To fully protect the device against vibration, dust and moisture
during transportation or storage use the original packaging or your own packaging material
suitable for transport or storage, respectively.

Establish all connections as long as the unit is switched off. Use the shortest possible high­quality cables for all connections.

Installation

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Balanced XLR chassis sockets serve as signal inputs. XLR chassis plugs serve as signal outputs.
Drawing and table indicate the XLR pin assignment.

1 Ground, shielding
2 Signal (+)
3 Signal (–)

Drawings and tables indicate the pin assignment for 1/4" phone plugs (unbalanced and bal‐
anced).

1 Signal
2 Ground, shielding

XLR connections for signal in
and outputs

Phone plugs for signal in and
outputs

Installation

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1 Signal (+)
2 Signal (–)
3 Ground, shielding

The unit has been designed for rack mounting in a standard 19-inch rack; it occupies one rack
unit.

Rack mounting

Installation

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5 Starting up

Connect the line outputs (left and right) of the audio device whose level is to be limited (for
example, your mixer) to the inputs of the limiter. Connect the outputs of the limiter to the line
inputs of your amplifier.

Connect the limiter to the power supply and switch it on. Test the threshold setting until the
amplifier is protected against overloading, but the limiting of the signal dynamics is only as
little as possible. To protect your speakers, proceed cautiously from an initially strong limiting
towards lower settings. If it is technically possible in your system, please try without connected
speakers first. Observe the operating instructions of the amplifier.

Starting up

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6 Connections and operating elements

Front panel

Connections and operating elements

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1 OUTPUT LEVEL

The LED chains indicate the output level of the left and right channel.

2 INPUT CLIP

This LED indicates an excessive input level overloading the input. If this happens, reduce the output level of the con‐
nected device.

3 LEFT LIMIT

Indicates active limiting in the left channel.

4 RIGHT LIMIT

Indicates active limiting in the right channel.

Connections and operating elements

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5 THRESHOLD

Rotary switch for threshold setting. Before adjusting this value, remove the transparent plastic cover and turn the
switch with a suitable screwdriver to the desired value between 9 dBu (bypass, no limiting) and –22 dBu. To protect
the switch against unintended adjusting, refit the plastic cover.

6 POWER

This LED indicates that the unit is turned on.

Connections and operating elements

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Rear panel

Connections and operating elements

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7 INPUTS

Right and left channel inputs

n XLR chassis socket
n 1/4" phone socket (balanced or unbalanced)

8 OUTPUTS

Right and left channel outputs

n XLR chassis socket
n 1/4" phone socket (balanced or unbalanced)

9 Slide switch for mains voltage setting.

10 IEC chassis connector with fuse holder.

Always make sure that the slide switch (9) is et to the correct position before you connect the mains voltage here.

11 Main switch to turn the device on or off.

Connections and operating elements

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7 Technical specifications

Inputs XLR chassis sockets, 1/4" phone sockets
Maximum input level +9 dBu
Outputs XLR chassis plugs, 1/4" phone sockets
Maximum output level +9 dBu
THD in ‘Bypass’ mode (–6dbFS) < 0.01 %
Frequency response, ±0,5 dB

20 Hz…20 kHz
Signal-to-noise ratio > 103 dBu (in ‘Bypass‘ mode)
Resolution (A/D and D/A conversion) 24 bit
Resolution (internal processing) 24 × 48 bit with 96 bit accuracy for intermediate steps
Attack time 80 µs
Release time 600 ms
Operating supply voltage

AC 220 – 240 V , 50 Hz

Technical specifications

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Power consumption 10.5 W
Fuse T500mAL250V (bei 115 V) | T 250mAL250V (bei 230 V)
Dimensions (W × D × H) 482 mm × 175 mm × 44 mm
Weight 2.5 kg

Technical specifications

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8 Cleaning

The fan grids of the device must be cleaned on a regular basis to remove dust and dirt. Before
cleaning, switch off the device and disconnect AC-powered devices from the mains. Use a lint­free damp cloth for cleaning. Never use solvents or alcohol for cleaning.

Fan grids

Cleaning

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9 Protecting the environment

For the transport and protective packaging, environmentally friendly materials have been
chosen that can be supplied to normal recycling.

Ensure that plastic bags, packaging, etc. are properly disposed of.
Do not just dispose of these materials with your normal household waste, but make sure that

they are collected for recycling. Please follow the notes and markings on the packaging.

This product is subject to the European Waste Electrical and Electronic Equipment Directive
(WEEE). Do not dispose with your normal household waste.

Dispose of this device through an approved waste disposal firm or through your local waste
facility. When discarding the device, comply with the rules and regulations that apply in your
country. If in doubt, consult your local waste disposal facility.

Disposal of the packaging mate‐
rial

Disposal of your old device

Protecting the environment

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Notes

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Notes

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Notes

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Musikhaus Thomann · Hans-Thomann-Straße 1 · 96138 Burgebrach · Germany · www.thomann.de