NTI MR-PRO Users Manual

3

NTI Contact Info

NTI AG
Im alten Riet 102
9494 Schaan
Liechtenstein, Europe
Tel.: +423 - 239 6060
Fax: +423 - 239 6089
E-Mail: [e-mail]
Web: www.nti-audio.com

© All rights reserved.
All information subject to change without notice
Version 1.3 / July 2007 / Software 1.10

® MiniLINK, Minilyzer, Digilyzer, Acoustilyzer, Minirator, MiniSPL

and Ministruments are registered trademarks of NTI.

Table of contents

1. Minirator Basics ..............................................................4

Introduction....................................................................4

Notes..............................................................................5

Scope of delivery............................................................. 6

Accessories .....................................................................6

2. Overview of the instrument ..........................................7

Connections....................................................................7

Buttons and operating elements......................................8

The screen display...........................................................9

Power supply ................................................................11

Characteristics of the outputs........................................12

3. Getting Started .............................................................14

Inserting the batteries ..................................................14

Fitting the protective shock jacket (MR-PRO only) ..........15

Attaching the hand strap ..............................................16

Connecting the Minirator ............................................. 17

4. Operation ......................................................................18

Switching the Minirator on and off ...............................18

Navigation in the menu bar........................................... 18

Selecting a test signal is easy.........................................19

Setting the parameters.................................................. 20

Setting the sensitivity of the rotary wheel ......................21

System settings ............................................................. 22

Congurations (MR-PRO only)....................................... 23

5. The Minirator test signals ............................................25

Sine ..............................................................................25

Table of contents

Sweep...........................................................................25

Chirp ............................................................................27

Delay Test......................................................................28

Pink Noise.....................................................................29

White Noise ..................................................................30

Polarity..........................................................................30

Wave File Player (MR-PRO only) .....................................31

6. The measurement functions of the MR-PRO ..............34

Display of impedances...................................................34

Balance display..............................................................35

Measuring phantom voltages........................................36

Testing XLR cables (MR-PRO only).................................. 37

7. Updating the instrument..............................................39

General rmware update: ............................................. 39

MR2: Updating the rmware.........................................39

MR-PRO: Updating the rmware...................................39

Calibration....................................................................40

8. Tips and trouble shooting............................................40

Resetting to the factory settings....................................40

Reloading Wave les (MR-PRO only).............................. 40

Faults and their correction............................................. 41

9. Technical data................................................................ 42

10. Further information....................................................44

Warranty conditions...................................................... 44

Declaration of Conformity............................................. 45

Information regarding disposal and recycling.................45

3

5

1. Minirator Basics

Introduction

Basics

Thank you for purchasing the Minirator. The Minirator is a power­ful audio generator, offering a wide range of analog test signals
for the calibration, maintenance and repair of professional audio
systems.

The rotary settings wheel combined with surrounding fast access
function keys enables instant and intuitive operation without
compromising ne adjustment capabilities.

While the MR2 has been optimized for “Value at a most attractive
price“, the MR-PRO has been developed with additional innova­tive functionality for even more demanding applications.

4

The MR-PRO is also equipped with the following functions:

• Integrated measurement functions for impedance, balance
and phantom power voltages

• Playback of WAV les

• Cable tester

• High output level

• True Level output stage

• Shock protection

Notes

Basics

Danger of electric shock

Never connect the instrument to a power
output!

Non-compliance could result in damage to
persons or property that is not covered by
the warranty.

Damage through damp

Do not use the instrument in damp
environments!

The instrument can be permanently
damaged by the penetration of water.

Damage caused by opening the
instrument

Never open the instrument.

The instrument can be damaged if the
housing is opened, and your warranty will be
invalidated.

5

7

Basics

Scope of delivery

The following items are included with the respective model:

MR2: • MR2

• Operating manual

• USB cable

• Hand strap

MR-PRO: • MR-PRO

• Protective shock jacket

• Operating manual

• USB cable

• Hand strap

Accessories

Accessories available for the MR2 / MR-PRO:

• Pouch MR2 / MR-PRO NTI Art.No 600 000 302

• System case NTI Art.No 600 000 020

• EU Power Supply 7.5V NTI Art.No 600 000 301

• Cable test plug NTI Art.No 600 000 311

• Calibration certicate NTI Art.No 600 000 303

You can nd more accessories and additional information on the
Internet under www.nti-audio.com

6

2. Overview of the instrument

Connections

The Minirator has the following connections:

Overview

1 2 3 4 5

1

RCA output (unbalanced)

2

XLR output (balanced)

3

DC power socket

4

XLR input for the cable test
(MR-PRO only)

5

USB connection (Mini-B, 5 pin)

7

9

wave

sens

mute

freq

esc

level

Overview

Buttons and operating elements

1 2 3

4

4

Wave Selection of the test signal.

5

Freq Setting the output frequency. Direct jump to

the “PARAM” menu with the “SWEEP” and
“CHIRP” test signals.

6

Mute Switches off the output signal.

Mute is indicated at the lower right corner of
the display.

9

8

1

ESC Terminates an entry and

7

jumps to the top menu level.

2

Rotary

wheel

Slow turning:
Precise setting of the value.
Rapid turning:
Setting the value in larger steps.

3

Enter Conrming a selection.

8

5

The button lights up continually during the
pauses of the “PNoise” and “Chirp” signal
waveforms.

7

On/Off Switches the instrument off if held down for

one second. Switches the back-lighting on

6

8

Sens Changes the sensitivity steps of the frequency

and off.

and level settings.

9

Level Setting the output level. You can set up the

output signal in the following units:
dBV, dBu,V.

With the MR-PRO, dBF (dB referred to Full
Scale) and % units are available when playing
back Wave les.

The screen display

Overview

The main menu

4

1 2

3

1

2

3

4

Menu bar
Battery symbol:
If the battery symbol lights
up the batteries are almost
completely discharged and
must be replaced.
Display of the readings
(MR-PRO)
Settings for signal generation

Settings for signal generation

1 2 3

7

6

5

1

Test signal

2

Start / Stop for certain test
signals

3

Setting up the parameters

4

Single / continuous mode for
certain test signals

5

Output frequency

6

Units for the output level

7

Output level

4

9

11

Display of the measured values (MR-PRO)

1 2 3

1

Phantom voltage

2

Balance

3

Impedance

Overview

10

Power supply

Battery operation

In order to be always able to use the Minirator exibly, we recom­mend the use of batteries.

Only use AA, LR6 batteries.

You will need 3 batteries for battery
operation.

During operation, the battery temperature
may increase noticeably. This is not a defect.

The Minirator can also be used with
rechargeable batteries.

Operation using the mains socket

You can also connect the Minirator to a mains socket with a
DC power supply unit. To do this, you will need the correspond­ing DC power supply unit, which you can order from NTI.

Overview

We recommend you use only the NTI DC
supply. But if you want to make use of a
different DC power supply unit, you must
observe the following:

Use an electrically-isolated, non-earthed
linear DC power supply unit.

Do not use a switching power supply.
Unbalanced connections in combination
with a switching power supply can lead to
noise interference and an unpleasantly high
interference level when plugging in and out.

Only use DC power supply units with a
voltage from 5 to 8 volts and a current of at
least 500 mA.

Damage caused by using an inappropriate
external DC supply is not covered by
warranty.

11

13

2

1

3

XLR

RC

A

~

~

100 Ω

MR2

U/2

U/2

U

100 Ω

0.5 Ω

Overview

Characteristics of the outputs

The Minirator has two outputs that are wired in parallel:
An unbalanced RCA output and a balanced, non-earthed XLR
output. Both outputs are resistant to externally applied phantom
power.
Wherever possible, always use balanced (XLR) connections, as
these have much better immunity to interference than unbal­anced connections.

Do not use both outputs at the same
time.

The simultaneous use of both outputs could
lead to a short-circuit in one of the generator
outputs in the connected instrument.

MR2 outputs

Both the RCA and the XLR have a balanced output impedance
of 200 Ohm.

The voltage at the MR2 XLR or RCA output
is less than the set voltage U with low
impedance loads. Example:

A balanced 200 Ohm load impedance
matching the 200 ohm output impedance will
result in the expected output drop of 6 dB.

Allocation of the XLR output:

2

12

3

1

1

PIN 1

2

PIN 2

3

PIN 3

2

1

3

XLR

RC

A

~

~

I<10mA

I<10mA

6.3

Ω

6.3 Ω

MR-PRO

U/2

U/2

U

0.5 Ω

MR-PRO outputs (True Level)

Both the RCA and the XLR have a balanced output impedance of
only 12.5 ohms. The level at the XLR output corresponds to the
set source voltage U (à True Level) over a wide range of loads.

Overview

XLR short-circuit between Pin 1 and 3

Commercially available XLR to RCA adapters
short-circuit the XLR Pins 1 and 3.

Do not use such adapters with the Minirator!

The MR-PRO is designed for loads down to
600 Ohm. Depending on the output level
and the output frequency, however, the True
Level is maintained, even with smaller loads.

Behavior with low-impedance loads

The maximum output current of the MR-PRO is 10 mA. If the
connected load consumes more power, the internal regulation
of the MR-PRO reduces the output level. This condition will be
indicated on the screen by the blinking of the output level display:

13

15





3. Getting Started

Getting Started

Inserting the batteries

Only use AA, LR6 batteries for the Minirator.

Only use batteries from the same
manufacturer.

Replace the discharged batteries by new
ones.

You can also use rechargeable batteries.

1. Open the battery cover.

2. Insert three AA, LR6 batteries with the same state of charge,
paying attention to the +/- marking in the battery compart­ment.

3. Close the battery cover once the batteries have been insert­ed.

C You have now successfully inserted the batteries.

14

Fitting the protective shock jacket

1.

2.

(MR-PRO only)

With the MR-PRO, you can t the supplied protective shock jack­et. This will protect the instrument against light impacts without
impairing its easy operation.

Getting Started

1. Push the lower end of your MR-PRO into the lower end of the
protective shock jacket.

2. Push the upper end of the MR-PRO into the protective hous­ing.

C You have now tted the protective shock jacket

Damage through impacts / shocks

The protective shock jacket shields your MR­PRO against reasonable impacts that could
occur in normal use.

But do not intentionally subject the
instrument to extreme stress!

Please do not drop the instrument!

Damage caused by dropping or impact is not
covered by warranty.

15

17

2.

1.

3.

Getting Started

Attaching the hand strap

To prevent you from accidentally dropping the Minirator, a hand
strap is supplied with the instrument. You can also t the hand
strap when the protective shock jacket of the MR-PRO has been
tted.

1. Pull the hand strap through the opening.

2. Pull the rear part of the hand strap through the loop of the
front part.

3. Pull the hand strap tight.

C You have now secured the hand strap.

16

Connecting the Minirator









Getting Started

XLR connection

1. Connect the Minirator to your audio device using an XLR ca­ble. Note that the locking pin of the plug must be located on
the lower side of the instrument!

C You have now connected the Minirator.

RCA connection

1. Connect the Minirator to the input of the unit to be tested
using a RCA cable.

C You have now connected the Minirator.

17

19

4. Operation

Operation

Switching the Minirator on and off

Switching the Minirator on

1. To switch the Minirator on, press the “On/Off” button.

C The display lighting is switched on.

You have switched on the Minirator.

Switching the Minirator off

1. To switch the Minirator off, press the “On/Off” button and
hold it down for one second.

C You have switched off the Minirator.

Navigation in the menu bar

The menu bar is divided into two parts. On the left-hand side, you
can choose between the Generator, Cable test (MR-PRO only)
and System functions.

1. To do this, select the left side of the menu bar with the rotary
wheel and conrm with “Enter”.

C A selection window opens.

2. Select the desired function with the rotary wheel.

3. Conrm the selection with “Enter”.

C You have now selected the desired function.

You can save and call up congurations on the right-hand side of
the menu bar (see the “Congurations” chapter, MR-PRO only).

18

Operation

Selecting a test signal is easy

You have two choices for selecting test signals. You can use either
the direct buttons or the rotary wheel.

Signal selection using the direct buttons

1. Ensure that GENERATOR

2. Press the “Wave” button.

C A selection menu appears.

3. Select the desired test signal with the rotary wheel.

4. Press “Enter”.

C You have now selected the test signal.

is selected in the menu bar.

1

Signal selection using the rotary wheel

1. Ensure that GENERATOR

2. Select “WAV”

3. Press “Enter”.

2

1

is selected in the menu bar.

with the rotary wheel.

C A selection menu appears.

1

2

4. Select the desired test signal with the rotary wheel.

5. Press “Enter”.

C You have now selected the test signal.

19

21

Operation

Setting the parameters

You have two possibilities for setting up the parameters for the
test signals. You can use either the direct buttons or the rotary
wheel.

Setting parameters using the direct buttons

1. Press the “Level” or “Freq” button.

C You have selected the desired parameter.

2. Turn the rotary wheel to set the parameter.

3. Conrm the setting with the “Enter” button.

C You have now set up the parameter.

Setting parameters using the rotary wheel

1. Turn the rotary wheel.

C The selected parameters will be marked with a black bar.

2. Conrm your choice with the “Enter” button.

C The parameter display blinks.

3. Turn the rotary wheel to set the parameter.

4. Conrm the setting with the “Enter” button.

C You have now set the parameter.

20

Setting the sensitivity of the rotary wheel

You can set up the sensitivity (step size) of the rotary wheel. To do
this, proceed as follows:

1. Select Level or Frequency with the rotary wheel.

2. Hold down the “Sens” button.

Operation

C The current sensitivity of the rotary wheel will be displayed

3. Turn the rotary wheel to set up the desired sensitivity.

4. Release the “Sens” button to accept the desired sensitivity.

C You have now changed the sensitivity of the rotary wheel.

1

.

1

21

23

System settings

Operation

You can adjust various system settings of your instrument. To do
this, switch to System
and conrm with “Enter”.

The possible system settings are displayed:

1

1

in the menu bar using the rotary wheel

2

3

4

5

Power Save

The Power Save mode switches the instrument off if no button
has been pressed within an adjustable time period.

1. Use the rotary wheel to select the Power Save function

2. Conrm the selection with the “Enter” button.

2

.

C The display starts to blink.

3. Turn the rotary wheel to set the desired time.

4. Conrm the entry with the “Enter” button.

C You have now changed the switch-on time of the Power-Save

mode.

Backlight

Auto:
The backlight will be switched on automatically during operation,
and will be switched off again after a period of time.

Manual:

1. Press the “On/Off” button to switch the background lighting
on and off.

You can choose between “Auto” and “Manual”.

1. To do this, select the Backlight
wheel.

2. Press “Enter”.

3

function with the rotary

C The display now changes between “Auto” and “Manual”.

22

Operation

Congurations (MR-PRO only)

Firmware

Display of the version number, with the possibility of carrying
out an update for the MR-PRO
chapter).

4

(see “Update instrument”

Display of the serial number

You can read out the instrument’s serial number
bottom line.

5

from the

Setting the contrast

Changing the contrast of the screen display.
To do this, proceed as follows:

1. Hold down the “ESC” button and turn the rotary wheel until
the desired contrast is obtained.

C You have now changed the contrast of the screen display.

With the MR-PRO, you can store your current instrument settings
as congurations, and can call these up again at a later date.

Storing congurations

10 conguration storage locations are available to you.

1. Using the rotary wheel, select CONFIG in the menu bar.

2. Conrm with “Enter”.

C The following menu is opened:

3. Select STORE and conrm with “Enter”.

C The following selection menu is opened:

23

25

Operation

4. Select a memory location with the rotary wheel and store
your conguration by conrming the selection with “Enter”.

C You have now stored the current instrument settings as a

conguration.

Calling up congurations

1. Use the rotary wheel to select CONFIG in the menu bar.

2. Conrm with “Enter”.

C The following menu is opened:

3. Select “Recall” and conrm with “Enter”.

4. Select the desired conguration in the Selection menu and
conrm with “Enter”.

C You have now loaded the desired conguration.

Transferring congurations to another device (MR-PRO)

With the MR-PRO, you have the possibility of transferring stored
congurations to another device.

1. Connect your MR-PRO to a computer via USB.

C A removable memory drive will be indicated on the

computer.

2. Select the CONFIG sub-folder.

C You will see the stored congurations of your MR-PRO.

3. Copy this data to your computer.

4. Connect another MR-PRO to the computer via USB.

5. Copy the previously copied data into the CONFIG sub-folder
by overwriting the data therein.

C You have now transferred congurations from your MR-PRO

to another MR-PRO.

24

5. The Minirator test signals

Test signals

Sine

Characteristics and use

Pure sinusoidal signals are required for almost every audio meas­urement. The Minirator provides a wide and adjustable output
level range and selectable output frequencies.

Parameters

You can dene the following parameters for this test signal:

Output frequency

Output level

Sweep

Characteristics and use

Sweep signals with a resolution of up to 1/12 octave can be
generated over a freely selectable frequency range. An audio
analyzer like the Minilyzer from NTI can automatically trigger to
this signal sequence to measure the frequency response.

Starting the Sweep signal

1. Select the “START” symbol with the rotary wheel.

C You can interrupt a running sweep via the „STOP“

symbol.

25

27

B

t

t

TRIG

t

STEP

f

RES

A

ff

f

t

STEPtSTEPtSTEP

f

STOP

f

START

1 kHz

Test signals

Sweep Signal modes

Using the “MODE” symbol, you can run the test signal in the
following modes:
Once-only : Plays the test signal once
Continuous : Repeats the test signal

Parameters:

You can dene the following parameters for this test signal:

Output level

The frequency display is for information only. The current

frequencies will be displayed here once the SWEEP test
signal has been started.

You can congure the signal sequence here.

A The sweep recording starts as soon as the frequency

drops from 1 kHz to fSTART.

B The end of the sweep will be signaled by a falling

frequency.

26

































Chirp

Characteristics and use

A Chirp is the name for a signal whose frequency continually
changes over time (also known as continuous sweep). It is used
for the recording of frequency responses, the measurement of
impulse responses and the acoustic assessment of rooms.

Starting the Chirp signal

1. Select the START symbol with the rotary wheel.

C If this is activated, it turns into a STOP symbol , which will

end the test signal when selected.

Chirp Signal modes

Using the “MODE” symbol, you can run the test signal in the
following modes:

Test signals

Once-only : Plays the test signal once.
Continuous : Repeats the test signal after an adjustable
pause (tPAUSE).

Parameters

You can dene the following parameters for this test signal:

Output level

The frequency display is purely for information only. The

current frequencies will be displayed here after the start
of the CHIRP test signal.

Conguration of the signal sequence

27

29

Fading in and out of any Chirp signal
generates spurious frequency components,
leading to ripple in the frequency response.

The Chirp sequences of the
MR-PRO / MR2 are optimized for ripple of
± 0.2 dB maximum.

Parameter combinations resulting higher
ripple are automatically corrected during
input.

Test signals

Delay Test

Characteristics and use

The Delay Test signal is a specially congured Chirp signal. In
combination with the Acoustilyzer AL1 from NTI, it makes it pos­sible to determine acoustic signal running times. You can nd
further information in the handbook for the AL1 Acoustilyzer.

Parameters

You can dene the following parameters for this test signal:

Output level

28

Pink Noise

1

2

Characteristics and use

The Pink Noise test signal has a high spectral density, an innite
period (> 100 years) and 20 kHz bandwidth. Pink Noise is used
as a reference signal for the layout of loudspeaker systems (PA
systems), whereby a Real Time Analyzer (RTA) is used to execute
the required measurements.

When operated in the intermittent mode, Pink Noise forms the
basis for reverberation time measurements.

Test signals

Operation

You can choose between the following test signal modes with
the MOD setting 1:
CONT : generates a continuous test signal.

: generates a intermittent test signal.

You can determine the cycle times of the intermittent signal with
the CYC setting 2.
(3/3 = 3 seconds of signal and 3 seconds pause.)
These settings have no effect in the continuous mode.

Parameters

You can dene the following parameters for this test signal:

Output level

29

31

Test signals

White Noise

Characteristics and use

The White Noise test signal has a high spectral density, Gaus­sian amplitude distribution and an innite period (> 100
years). White Noise is used for all measurements with FFT
analyzers, and has a constant signal power per Hertz and a
20 kHz bandwidth.

Parameters

You can dene the following parameters for this test signal:

Output level

Polarity

Characteristics and use

The sawtooth test signal is ideally suited for checking the polarity
of loudspeakers. The “Minilyzer ML1” and “Acoustilyzer AL1” in­struments from NTI detect this signal and determine the polarity.

Parameters

You can dene the following parameters for this test signal:

Output level

The frequency display is for information only.

The frequency cannot be adjusted.

30

Wave File Player (MR-PRO only)

1

2

Characteristics and use

You can play back your own test sequences with the MR-PRO.
The test sequences will be repeated automatically and without
pauses.
For a better overview, Wave les are organized in sub-folders.

The MR-PRO is already equipped with a series of demo sequences
in the WAV le format. You can create a link to a computer at any
time via the USB interface and can exchange existing WAV les
or add new ones.

Test signals

Possible applications

Possible applications include, for example:

• Identication generator in the broadcasting sector

• Musical signals for the assessment of PA systems

• Playing back complex test signals

Selecting a folder

1. Select the Symbol folder 1 with the rotary wheel.

2. Conrm with “Enter”.

3. Select the desired folder with the rotary wheel.

4. Conrm with “Enter”.

C You have now changed the current playback folder.

Selecting a Wave le

1. Use the rotary wheel to select the Symbol le 2.

2. Conrm with “Enter”.

3. Select the desired WAV le with the rotary wheel.

4. Conrm with “Enter”.

C The WAV le will be played.

31

33

WAVE

FOLDER1 FOLDER2 ...

• Signal1.wav

• Signal2.wav

• ...

• Signal1.wav

• Signal2.wav

• ...

Test signals

Loading your own WAVE les

Wave les for the MR-PRO must fulll the following require­ments:

• 48 kHz sampling frequency

• Mono / Stereo

• 16-bit denition

If a Wave le does not meet the
requirements, the playback stops and the
“Mute” button lights up continuously red.

To load WAV-les, you will need a computer
with the following minimum specications:

• PC with Windows 98SE

• Macintosh computer with OSX

1. Connect the MR-PRO to the computer via USB.

C The MR-PRO appears on your computer as a removable data

32

medium.

2. Open the “WAVE” sub-folder on the removable medium

All the sub-folders in the “Wave” folder
now appear in the folder selection . Add
additional sub-folders to this folder level as
required.

1

Test signals

3. Open one of the sub-folders in the “WAVE” folder.

If necessary, you can make use of the other
standard possibilities of a removable data
medium. For example, you can copy WAV
les from the MR-PRO onto your computer
or delete unnecessary les.

4. Copy the desired les into the folder.

C You have now loaded your Wave les.

Copyright

NTI delivers a set of demonstration wave les
with the MR-PRO. These wave les may only
be replayed with an NTI unit (MR-PRO). Any
further usage is forbidden.

Parameters

You can dene the following parameters for this test signal:

Output level

The output level of this test signal is adjusted in
dBF (dB full scale) or %.

The absolute level generated at the output
depends on the modulation as well as the
signal form of the data present in the WAV
le.

Example: A fully modulated sinusoidal signal
played back at 0 dBF generates an absolute
level of 18 dBu at the output.

33

35

Meas. functions (MR-PRO only)

2

1

3

R2

R3

XLR

RCA

6. The measurement functions of the MR-PRO

The MR-PRO measures phantom voltages and displays impedances and the impedance balance in the SINEWAVE operating mode.

MR-PRO

Display of impedances

Using the SINEWAVE sinusoidal test signal, the MR-PRO meas­ures the load connected to the output between PIN 2 and 3
(RL=R2+R3). The measured values of R2 and R3 will be displayed
by selecting RL with the rotary wheel.

If only R2 or R3 can be measured, RL is replaced by R2 or R3 ac­cordingly.

In the case of balanced connections (XLR),
interference radiated onto the receiver side
will be eliminated.

For this to work there must be a balanced
impedance distribution on both signal
lines. In the case of unbalanced impedance
distribution, signal interference could occur.
The MR-PRO allows you to test the
connections for balance.

34

The impedance and balance measurement
can only be carried out down to a dened
minimum level. If the measurement cannot be
carried out, the display shows:

Balance display

The balance display allows localizing a number of typical faults,
such as short-circuits and defective cables.

In the case of an unbalanced impedance distribution, the display
arrow points to the pin with the higher impedance.

Balanced impedance, R2 = R3

Unbalanced impedance, R3 > R2

Unbalanced load relationships can be analyzed further by select­ing the impedance display with the rotary wheel. If the imped­ance cannot be measured, the display shows “---” instead of the
measurement value.

Meas. functions (MR-PRO only)

35

37

Meas. functions (MR-PRO only)

2 x 6.8k

V2

V3

2

1

3

+48V

R2

R3

XLR

Measuring phantom voltages

The phantom voltage is necessary in connection with capacitor
microphones in order to operate the impedance converter locat­ed in the microphone as well as for some “active” direct boxes.

MR-PRO

Mixing desk

The most common phantom voltage is 48 V and lies on both
Pin 2 and Pin 3 with balanced impedances (see diagram).

36

1

Unequal phantom voltages on Pin2 and Pin3 of the XLR cable
indicate an error and will be displayed by the blinking of the
phantom voltage display (DC).

You can localize the faulty voltage source by selecting the DC
function

1

with the rotary wheel.

Testing XLR cables (MR-PRO only)

2

1

3

R2 = 1k

R3 = 2k

XLR

Cable

Out

XLR

In

1.

2.

Meas. functions (MR-PRO only)

The MR-PRO supports a cable test function that quickly detects
damaged cables.

The cable test is based on an impedance measurement. In order
to indicate a correct XLR cable, the test routine of the MR-PRO
assumes the following impedances on the output:

MR-PRO

MR-PRO or adapter

To test a cable, proceed as follows:

1. Select the “Cable test” function in the menu.

2. Plug the XLR cable into the XLR output (1).

3. Plug the other end into the XLR input (2).

37

39

Meas. functions (MR-PRO only)

C The following is displayed on the screen:

The cable has not been
plugged in correctly. Check
the cable connection.

The tested cable is defective.

The tested cable is OK.

For long cables already in place, NTI has an
optional adapter. Plug one end of the cable
into the adapter and the other end of the
cable into the MR-PRO. The adapter can be
obtained from NTI as an accessory: Cable
Test Plug, NTI Art.No 600 000 311.

You can nd further information on the
Internet under http://www.nti-audio.com.

38

7. Updating the instrument

Updating the instrument

General rmware update:

The rmware is the software of the instrument. Updating is pos­sible by connecting your Minirator to a computer via USB.
You can nd the rmware version of your instrument as follows:

1. Select “System” in the menu bar.

2. Conrm the selection with the “Enter” button.

C The rmware version of the instrument will be displayed.

In order to update the rmware, you
will need a computer with the following
minimum specications:

• PC with Microsoft Windows 2000

• USB termination

You can nd information about the latest available rmware and
the procedure for the update under
http://support.nti-audio.com/mr2

MR2: Updating the rmware

Proceed as follows to update the rmware:

1. Connect your MR2 to the USB connector of a PC and follow
the instructions on the screen of the MR2.

C You have now updated the rmware of your MR2.

MR-PRO: Updating the rmware

Proceed as follows to update the rmware:

1. Select “System” in the menu bar.

2. Click on Firmware and follow the instructions on the screen of
the MR-PRO.

C You have now updated your MR-PRO.

39

41

Trouble shooting

8. Tips and trouble shooting

Calibration

The Minirator has been carefully tested during production and
corresponds to the specications listed in the “Technical Data”
chapter.

NTI recommends regular calibration of the instrument in annual
intervals. Please contact your dealer for information regarding
calibration or contact NTI directly on the E-Mail address info@nti­audio.com

Resetting to the factory settings

If the Minirator reacts unexpectedly, a reset to the factory settings
might solve the problem.

1. Switch the instrument off.

2. Hold down the “ESC” button and simultaneously operate
the “On/Off” button.

C The conrmation of the reset is displayed on the screen.

Reloading Wave les (MR-PRO only)

You can reload the Wave les of the MR-PRO that were installed
in the factory.

The les are available on the Internet. Please visit
http://support.nti-audio.com/mr2 for further details.

40

Trouble shooting

Faults and their correction

Fault Fault nding Cause Remedy

The MR2 does not generate
an output signal.

Screen contrast poor. Contrast needs to be

MR-PRO: Wave les are not
played back

MR-PRO indicates no
impedance.

“Mute” button blinks. You have switched the

instrument to Mute.

“Mute” button lights up
continuously.

“Mute” button lights up
continuously.

The lowest line is not
displayed.

You have called up the “Pink
Noise” (PNoise) test signal or
you are in the Pause cycle of
the Chirp test signal.

Cable not plugged in correctly.

adjusted.

Non-supported Wave format. Load a supported Wave

Output level too low.
Incorrect test signal.

Press the “Mute” button.

Wait until the pause has
ended.

Press the “Start” button.

Plug in the cable correctly.

Press “ESC” and operate the
rotary switch to set the
contrast.

format.

Increase the output level.
Change to the SINEWAVE test
signal.

41

43

Technical data

9. Technical data

MR2 MR-PRO

Outputs Balanced XLR, unbalanced RCA

Inputs DC power supply, USB DC power supply, USB

Signal wave forms Sine, Pink Noise, White Noise

Wave File Format Sampling freq.:

Frequency setting Range:

Stepped Sweep Function Freq. range:

Continuous Sweep (Chirp) Function Freq. range:

Level Units dBu, dBV, V dBu, dBV, V, dBFS, %

Output Level Ranges Sine, Sweep, Chirp

Flatness RL ≥ 600 Ohm ± 0.5 dB ± 0.2 dB

Accuracy @ 1kHz ± 0.5 dB ± 0.2 dB

Resolution:
Output level:

Increment:
Accuracy:

Increment:
Sweep speed:

Increment:
Chirp speed:

White Noise
Pink Noise
Polarity, Delay Test

-80 dBu to + 8 dBu

-80 dBu to + 0 dBu

-80 dBu to - 2 dBu

-80 dBu to +6 dBu

phantom power resistant

XLR for cable test

Polarity test signal, Delay test signal

48 kHz

16 Bit, Mono / Stereo

0 dBFS = 18 dBu (sine)

according to EBU R68

10 Hz - 20 kHz
in 1 digit steps

0.01%

freely selectable
1/1, 1/3, 1/6, 1/12 octave
selectable 0.5 - 5 seconds

freely selectable

Linear / Logarithmic

0.5 - 20 seconds per cycle

- 80 dBu to +18 dBu

- 80 dBu to +10 dBu

- 80 dBu to + 8 dBu

- 80 dBu to +16 dBu

42

Technical data

MR2 MR-PRO

THD+N 22 Hz - 22 kHz, average,

@ 1 kHz, typical

Output impedance 200 Ohm (balanced) 12.5 Ohm balanced, Imax = 10 mA

Impedance measurement Method:

Meas. range:

Accuracy:

Phantom voltage Meas. range:

Accuracy:

USB functionality Firmware update Firmware update

Flash memory 32 MByte for storing wave les and

Display Graphical, with back light

Auto-Power-Off 10, 30, 60 minutes or OFF

Batteries 3 x AA Alkaline dry cells or rechargeable equivalents

Battery Life 0 dBu, no load, typ. 20 hours 10 hours

Temperatue range 0° to 45° C (32° to 113° F)

Humidity < 90% rel. humidity, non-condensing

Dimensions (LxWxH) 147 x 74 x 41 mm 152 x 81 x 43 mm

Weight including batteries 250 g (9 oz.) 310 g (11 oz.)

-90 dB (0.0032%) @ 8 dBu,
Noise oor < 25 μV

-96 dB (0.0016%) @ 18 dBu,
Noise oor < 15 μV

Absolute value Z

4 Ohm - 50 kOhm balanced

2 Ohm - 25 kOhm unbalanced

@ f = 30 Hz to 10 kHz (Sine)

@ Level from -20 to +18 dBu

± 10 % or ± 2 Ohm

0 - 54 V

± 3 % or ± 0.5 V

Mass Storrage Device

congurations

(incl. protective shock jacket)

43

45

Further information

10. Further information

Warranty conditions

International warranty

NTI guarantees the function of the MR2 and MR-PRO and their
individual components for a period of one year from the date of
sale. During this period, defective instruments will be repaired
free of charge, or will be replaced.

Limitations

These guarantee provisions do not cover damage caused by ac­cidents, transportation, incorrect use, carelessness, accessories or
the installation of any parts that were not delivered with the in­strument, the loss of parts, connection to the mains voltage, op­eration with non-specied input voltages, adapter types or incor­rectly inserted batteries. In particular, NTI accepts no responsibility
for subsequent damage of any kind. The warranty will be voided
by the carrying out of repairs or service work by third parties who
are not part of an approved NTI Service Centre.

44

Repair of the Minirator MR2 / MR-PRO

In the case of faulty functioning or damage, send the instrument
to the local NTI agency in your country in its original packaging.
Please enclose a precise description of the fault. You can nd the
contact addresses on the NTI Internet page www.nti-audio.com
Repair work will only be carried out under warranty upon pre­senting the original sales receipt.

Further information

Declaration of Conformity

CE / FCC Compliance Statement

We, the manufacturer
NTI AG
Im alten Riet 102
9494 Schaan
Liechtenstein, Europe

hereby declare that the Minirator MR2 and Minirator MR-PRO
products, approved in 2007, comply with the following standards
or other standard documents:

EMC: 89/336, 92/31, 93/68
Harmonised standards: EN 61326-1

This declaration will become invalid if modications to the instru­ment are carried out without the written approval of NTI.

Date: 01.12.2006
Signature:

Information regarding disposal and

recycling

Dispose of your instrument in accordance with the

valid legal environmentally regulations in your country.

Regulations for the European Union and other European
countries with corresponding laws:

The instrument must not be disposed of in the household gar­bage. At the end of its service life, bring the instrument to a col­lecting point for electrical recycling in accordance with the legal
regulations.

Other countries outside the EU:

Contact your respective authorities for waste disposal and follow
their regulations.

Position: Technical Director

45

For your notes

46