MRC EQ Limit User Manual
®
Limit
USER´S MANUAL
Version 2.19 january 2019
www.mrcaudio.com
SECURITY ADVICE
1
Category I device.
All sockets are isolated from mains
Always use the earth lead in mains cord
Keep these instructions. Heed all warnings. Follow all instructions.
Do not expose this device to rain or moisture. Do not use this apparatus near water - for
example, swimming pool, fountain. Do not place any objects containing liquids, such as
bottles or glasses, on the top of the unit. Do not splash liquids on the unit.
Clean only with a dry cloth. Do not use any solvent based cleaners.
Do not install near any heat sources such as radiators, heat fans, stoves, or other
apparatus that produce heat.
Never disconnect or disable the grounding of the power cord. Make sure that the base
where you connect it has a good grounding.
Always connect the equipment to an adequately protected voltage socket with safety
elements and easy access.
Unplug this apparatus during lightning storms, earthquakes or when unused for long
periods of time.
No user serviceable parts inside. Refer all servicing to qualified service personnel.
Servicing is required when the apparatus has been damaged in any way, such as powersupply 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.
TO REDUCE THE RISK OF FIRE REPLACE THE MAINS FUSE ONLY WITH A FUSE
THAT CONFORMS TO IEC127-2. 250 VOLTS WORKING, TIME DELAY TYPE AND
BODY SIZE OF 20mm x 5mm. THE MAINS INPUT FUSE MUST BE RATED AT 230V=T
3,15AL and 115V=T 6,3AL.
MRC AUDIO EQLimit
2
CONTENTS
2
Chap. Pag.
1 Security Advice 2
2 Contents 3
3 Introduction 4 - 5
Block diagram 6
4 Description 7 - 8
5 Installation 9
5.1 Connections 10
5.2 SCL software installation 11
5.3 Limiter Password 11
5.4 Master Password 12
6 Cinfiguring panels 13
User´s Data 14
Installations 15
User´s manual 16
Backup 16
7 Programming 17 - 18
7.1 Installation File 19
7.2 Limiter adjust 20 - 21 - 22
7.3 Levels and Timetable 23 - 24 - 25
7.3.1 AUX Levels and Timetable 25
7.4 Limiter 26
7.4.1 Calibration process 27 - 28
7.5 Display 29
7.6 Isolation 30 - 31- 32 - 33
7.7 Registry 34
7.8 Events List 35 - 36 - 37 - 38 - 39 - 40
7.9 Graphs 40 - 41
7.10 Preferences 42 - 43 - 44
8 Technical characteristics 45
9 Warranty 46
10 Remote Display DD-1 47
11 Remote Display DD-3 48 - 49 - 50
12 Certification 51 - 52 - 53
MRC AUDIO EQLimit
3
INTRODUCTION
3
Thank you for using the Limiter-Controller MRC AUDIO EQLimit, the most complete system
for controlling the sound emission in public leisure establishments. This equipment adjusts the
sound emission in a musical system, acting softly on the audio signal what warranties that the
sound level inside the house does not exceed the maximum, avoiding in this way infringing the
corresponding local rules, and ensures a perfect coexistence with possibly affected
neighbours.
Specific and calibrated microphones are used in this equipment to detect the sound pressure
level. The generated signal is weighted as for “C”, “A” or “BASS” curves and is registered
periodically with programmable frequency and registering all sound parameters: Leq5s, LeqT
prog, L10, L90. These parameters can be measured also through a second sensing
microphone. The in&out audio signals is also registered for a combined evaluation.
This signal is compared to the levels and timetables adjusted during the programming of the
unit. As the maximum sound level is exceeded the equipment starts limiting. Beyond this point
and even if the input signal grows, the sound level in the house won’t grow over the level fixed
as the limit. The limiter’s action is shown by a group of LEDs marked with 5, 10, 15, 20, 30 and
40dB of attenuation. Although the limiter does not show further, it will still carry on limiting up
to over 60dB. The input overload is signalled by the AUDIO LED on the front and on the remote
display. It is also possible to use the audio signal as the limiting source instead of the signal
measured by the microphone. In both cases it is possible to adapt the limiting spectral curve
to the house’s isolation spectral curve by means of a spectral meter with 12 1/3 octave filters.
The limiting circuitry is one of the important advantages of this equipment, because it calculates
in a predictive manner, the possible boost of sound level and thanks to its elaborated design
avoids the unpleasant pumping effect and/or breathing sound other limiters have, offering high
quality sound even at high attenuation levels.
Also, it reminds the last attenuation level when the input audio signal is interrupted, avoiding,
in this manner, high level sound peaks when the signal is back on.
The control circuit is based on a powerful microprocessor that permits measuring both
microphones, input line, output line and the 12 1/3 octave filters in real time. It also registers,
and shows on screen all the events, including alarms, that might arise, together with their date,
time, and sound levels in dB, per each.
It regulates all the work time with three different working maximum levels per each day of
the week. In this way, it is possible to have different maximum permitted sound levels
depending on the hour of the day or depending on the day of the week; or alternatively it
is possible to have the same maximum permitted level all the time.
It changes automatically from winter to summer time.
It has the possibility to program up to ten special periods between any two-year days, in
which levels and/or timetables may be altered, intended for special occasions.
It registers the date of the programming changes, as it also registers the user’s license of
the technician that makes those changes.
Sound levels are registered periodically during the working sessions.
MRC AUDIO EQLimit
4
As prevention against manipulation of the system, the limiter has a circuitry that detects
different actions on the microphone like changing the original microphone, covering it with
sound isolating material, changing its location, etc. It registers the date and time of the
moment of the manipulation and mute the sound if desired.
All these events are kept in a non-volatile memory, with capacity for over 4 months of activity
(registering sound levels every 5 minutes).
To avoid improper manipulation of the system, all the configuration and programming of the
unit is only possible through proprietary software installed in a PC. It is necessary to register
this software prior its first use and introduce a user’s license that is provided for each authorized
user, license that identifies him in each access to the unit.
Optionally, the limiter can be provided with an internal ETHERNET adapter and/or an external
GPRS modem, with which real time control is possible through Internet, in a web page
restricted to authorized and subscribed to SICREL system users.
It also has physical protections with sealing screws at the connections back plane and for the
microphone’s cover.
As a complement for its installation and configuration, the limiter has an internal pink noise
generator.
All these elements are shown in the block diagram in fig.1
MRC AUDIO EQLimit
5
“C” “A”
LEFT LINE INPUT
VCA
SUM
SUM
R
E
L
A
Y
S
LEFT
LINE OUT
RIGHT LINE INPUT.
VCA
RIGHT LINE
OUT
FILTER
MIC 1
FILTER
“C” “A” “BASS”
MIC 2
FILTER
BANDS
FILTERS
uC
DISPLAY
COMMS
FIG 1
MRC AUDIO EQLimit
DESCRIPTION
4
The next text refers to fig.2 that shows the indicators and necessary connexions for a proper
use of EQLimit
1. NOISE – The limiter has an internal pink noise generator that leads to a more
comfortable adjusting of the installation. When clicking on the buttons NOISE or CAL,
the signal of this generator is mixed with the audio inputs. Also, this yellow LED starts
to blink.
2. AUDIO LEVEL – Three LEDs show the state of the sound level: Green shows presence
of normal signal, Yellow shows the audio level is above the permitted maximum, and
Red shows the limiter has shut off sound.
3. LIMITING LEDs – LEDs that show the amount of dynamic attenuation applied o the
input signal and input peak.
4. STATUS LEDs – LEDs that show the states of alarm, off time and special period active.
5. USB – USB connector for a direct connexion to a PC.
6. MAINS INPUT – Normalized IEC power input connector with Earth connection and input
fuse. The protecting fuse must always be substituted by one of the same type T
3.15A/250V. Universal power supply 90 to 250VAC.
7. DISPLAY – Connector for the remote display.
8. LEVEL -- Control of the signal level from external emergency message.
9. AUX – Auxiliary connections to drive an optional relay box to control external equipment
and fire alarm input to activate the priority of an external fire evacuation message or
level reduction.
10. MODEM – RS232 connector for the external optional GPRS modem.
11. LAN – Optional Ethernet connector for an ADSL router.
12. MODEM POWER FEED – Jack connector to feed the optional external GPRS modem,
with selectable 5 or 15Vdc, by means of internal jumper, with LED indication of the
selected voltage.
13. XLR OUT – Output balanced connectors for channels left and right.
14. AUX – Level control for the external fire evacuation message.
15. XLR IN – Input balanced connectors for channels left and right.
16. MIC1 - 2 – Input balanced connectors for main microphone 1 and optional registering
microphone 2.
MRC AUDIO EQLimit
7
FUSE
10
5
15
20
-
-
PEAKMUTE
NOISE
-
-
OK
PRE
GAIN REDUCTION
1 2 3
9
SERIAL NO
E172301
FOR SAFETY OPERATION, PLEASE,
REFER TO USER´S MANUAL
6
PUSH
DISPLAY
7
AUX OUTPUT
L R
LEVEL
AUX
8 11 12 13 14 15
OFF TIME
ALARM SPECIAL
4 5
10
LAN
15V
RS 232
5V
DC OUT
-
USB
RL
L
PUSH PUSH
EQ Limit
Sound Level Controller
R
PUSH PUSH
+
OUT
IN
MIC 2
MIC 1
MRC AUDIO EQLimit
Fig . 2
POWER
AMPLIFIER
DISPLAY
INSTALLATION
5
PUSH PUSH
IN
EQLimit
Sound Level Controller
PUSH PUSH
MIC 1MIC 2
RS 232
OFF TIME
USB
LAN
DC OUT
+
-
15V
5V
RL RL
OUT
20
-5-15-10-
PRE ALARM SPEC IAL
OK PE AKMUTE
NOISE
SE RIAL NO
E182401
FUSE
FOR SAFETY OPERATION, PLEASE,
REFER TO USER´S MANUAL
DISPL AY
GAIN RED UCTION
LEV EL
AUX OUTPU T
L R
AUX
PUSH
MICRÓFONO
MIXER
FIG. 3
This unit has been carefully packed at the factory inside a specially designed case.
Nevertheless, we recommend you supervise the state of the box and its contents.
Please do keep all the packaging items in case the unit should go back to MRC Audio.
MRC AUDIO EQLimit
9
The content of the box is:
EQLimit
MS1 Microphone
Remote display DD1 (optional)
USB cable
Power feed cable
Backplane cover TP2
Microphone cable CM10
NOTICE: The graphics included represent the equipment with all its accessories. Some may
be optional. If you need an accessory, include it in your order.
5.1.- Connections
Input and output connexions are made by means of XLR-3 connectors. The connection
pin out follows the international standard: Pin 1 is signal ground, Pin 2 (+) is non-inverted
and pin 3 (-) is inverted. Please be sure to follow the same scheme in both channels to
avoid phase cancellation problems.
Connect input and output audio signals (13 and 14) in such a way that the limiter is
connected just before the crossover or power amplifiers if there is no crossover.
Either balanced or unbalanced lines are used, be sure to follow the same pin out at both
channels to avoid phase cancellations.
Connect the microphone(s) to the MIC1 and MIC2 (optional) (15). Position the
microphone in a centred position with respect to the speakers in order to measure both
audio channels. Try to position the microphone as near as possible to where the
authorities would control the sound level from music, not the audience.
Optionally connect the remote display by means of its cable to the connector DISPLAY
(7). The remote display cable is 5 meters long.
Finally, connect the mains cable supplied with the unit to the mains input and the unit
will switch on. Do always connect the earth connection for your personal security.
Test for correct sound. If the remote display is installed verify that the metering varies
according to the sound level in the house. If display Und (35dB or less) maybe the cable
is connected in wrong way and sounds mute.
MRC AUDIO EQLimit
10
5.2.- SCL Software installation
Download from www.mrcaudio.com the executable SCL v2.xx. Run this executable in your
PC and follow instructions on screen. Once installed the icon appears on your desktop.
Double clicking this icon runs the software for EQLimit setup and control. Always open this
program as administrator
Before attempting to adjust the limiter, you must request to MRC Audio (info@mrcaudio.com)
an installer’s license and register this license in the User Data window. Fill up all user data and
register your license. When activated, check the “Remember in this PC” tick.
This license identifies the installer every time he makes a configuration change in the limiter. If
you do not have a valid license the limiter works in Demo mode, where no changes to the
limiter’s configuration are possible.
5.3.- Limiter’s password
Besides needing a user’s license for the SCL software, every time you attempt to change any
configuration parameter in the limiter, the limiter will request a password to permit changes.
For this purpose an emerging window will appear to input the password:
Enter the limiter’s password. The default password for all limiters is 1234. This password can
be changed by the user as described further on.
Once the password has been entered once, it will not be requested for further changes unless
a period of at least 5 minutes exists between two successive changes, or if the software is
restarted.
If a valid password is entered, the emerging window disappears and the changes are made in
temporary volatile memory. If the limiter is switched off, these changes are lost. This is why a
“Save Changes” button appears at the bottom left corner each time changes are made:
Clicking on this button makes the changes permanent and stored into non-volatile memory and
the button disappears until new changes are made.
Also, if the screen is exited and changes have not been saved, an emerging window appears
inviting to save changes:
MRC AUDIO EQLimit
11
On this emerging window Yes saves changes, No continues exiting the window without
saving changes and CANCEL cancels exiting and redirects back to the actual screen.
The save changes process is repeated each time any configuration changes are made
into the limiter, but also, it is possible to save changes only once after making all the
changes wanted.
5.4 Master Password
If the user forgets the password to configure the limiter, MRC Audio can provide a master
password valid for only that limiter, as a function of its serial number, and valid only once.
Introducing a master password is registered in the limiter’s non-volatile memory as an event,
together with the date and time as all other events, and together with the authorised user that
has entered the master password.
NOTICE: Each MRC Audio EQLimit has up to ten master passwords. Each time one is used it will not work
ever again. If all ten master passwords are used and still the user keeps on forgetting the password, the limiter
will have to be serviced at MRC Audio to restore ten new master passwords.
MRC AUDIO EQLimit
12
C
ONFIGURING PANELS
6
To open the program, always activate the "Run this program as administrator" box in Properties
and Compatibility tab of icon .
Clicking on this icon, created on the desktop at software installation time, the initial window
appears where you can choose the user´s language through its corresponding flag.
Once clicked on the language flag, the rest of buttons change to the language chosen.
MRC AUDIO EQLimit
13
USER’S DATA – This button takes us to the next screen, where it is possible to fill in the
software’s user data and the license provided by the manufacturer.
In the User field, fill in exactly the user name provided by the manufacturer. This name will
identify you when accessing any EQLimit.
In the License field type in the license number provided by MRC Audio; this field is case
sensitive.
Please fill in all fields, including the logo of your company, as this data will appear at the
headings of the reports.
Click on the Save Data button and then on the Activate button and the software will be ready
to use.
If the Remember me in this PC box is checked, the application remembers your license
number not needing to type it in each time the application is launched. But remember that
anybody using this PC will also not need to type in any license number at launching and
therefore anybody can make changes to limiters in your name.
EXIT goes back to the initial window.
MRC AUDIO EQLimit
14
Again, at the initial window the rest of the buttons are:
INSTALLATIONS – Opens the window with the list of installations kept in the data base and
with the required buttons to connect to an EQLimit.
Any data base installation can be opened in read only mode clicking on the corresponding
numbered button in the left column.
Search: Finding installations is possible by typing the name or part of the name or any
identifying word into the Search box and clicking on the Search button.
Delete: Installations can be erased by clicking on the Delete Button; the button changes to
Select Installations. Cancel/Continue and colour blue. Once the delete button changes, click
on one or more installations by means of their left hand numbered buttons. Each time a button
is clicked it changes to blue colour. Once all installations wanted to erase have their left hand
numbered button coloured blue, click on the Click here to delete button, now colour yellow,
to erase them permanently. This action is not reversible, therefore be sure you have chosen
the wanted installations before deleting.
If you do not want to delete any or all installations, unselect them by clicking again on its blue
button that will change back to its normal grey colour. If all installations are deselected, the
Click here to delete button changes again into Select Installations. Cancel/Continue and
colour blue. Click on the button to go back to the initial state without deleting anything.
NOTE: on top of the numbered left-hand buttons there is a button with an asterisk; clicking on
this button alternatively selects/deselects all installations.
MRC AUDIO EQLimit
15
Download to limiter: It is possible to download the entire configuration from a database limiter
into the actually connected limiter. Obviously, it is mandatory to be connected to an EQLimit
before proceeding with this action.
Click on the yellow Download to limiter button. This action will change the installations’ lefthand numbered button into yellow colour. Click on the chosen database installation’s left-hand
numbered yellow button and the entire configuration of that database limiter will start
downloading into the connected limiter.
Be patient, this action may take some seconds. Wait for the download to complete; the USB
red LED, on the connected limiter, blinks as data is transferred while downloading, and stops
blinking when the action is finished.
Export ---> It is also possible to export the entire configuration of one or more database limiters
to a file within the PC with the extension .mef in order to share database installations with other
PCs, or simply as a back-up method.
Like with the delete button, click on the Export ---> button that changes to blue, choose the
wanted installations, again the asterisk button alternatively selects/deselects all installations,
and click again on the now Click here to export and colour green, to export the installations.
This will open an OS window that permits choosing the name and location of the export file.
Import <--- This button imports into the SCL database any exported .mef files. Clicking on this
button changes it into Importing… and colour red and opens an OS window to look inside the
PC for the .mef file that is to be imported. Once chosen the file to be imported with the OS
window, the application adds the contents of the .mef file to the SCL database, the OS window
disappears and the import button goes back to its initial state.
The connect button and log window are explained further on.
The EXIT button goes back to the initial window.
Back at the Initial window:
USER’S MANUAL – This button opens a .pdf file with this user’s manual in the language
chosen for the application.
BACKUP – Creates a backup file (*.mrb) with the entire current database to reinstall in a
different PC or for after a total formatting of the disk.
Clicking on this button an emerging window appears inviting to create or to restore a database:
Click on any of both, an OS window appears to select the name and location of the file to create
or to find the file to restore.
MRC AUDIO EQLimit
16
Loading...