OPERATING MANUAL MINIRATOR MR2 / MR-PRO
NTI Contact Details Head Office NTI AG Im alten Riet 102 9494 Schaan Liechtenstein, Europe Americas NTI Americas PO Box 131027 Tigard, Oregon 97281 USA China NTI China Room 722, 7F, Building 6-3A, No 1388, Bin He Rd. 215000 Suzhou, China Japan NTI Japan Ryogokusakamoto Bld. 1-8-4 Ryogoku, 130-0026 Sumida-Ku Tokyo, Japan Tel.: +423 239 6060 Fax: +423 239 6089 E-Mail: info@nti-audio.com Web: www.nti-audio.com Tel.: +1 503 684 7050 Fax: +1 503 684 7051 E-Mail: americas@nti-audio.com Web: www.ntiam.
Table of contents Table of contents 1. Minirator Basics ..............................................................4 Introduction ....................................................................4 Scope of delivery.............................................................4 Notes ..............................................................................5 Accessories .....................................................................6 2. Overview of the Instrument .............................
Basics 1. Minirator Basics Introduction Scope of delivery 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 following items are included with the respective model: The rotary wheel combined with surrounding fast access function keys enables instant and intuitive operation without compromising fine adjustment capabilities.
Basics Notes Danger of electric shock Damage caused by opening the instrument Never connect the instrument to a power output! Never open the instrument. Non-compliance could result in damage to persons or property that is not covered by the warranty. The instrument can be damaged if the housing is opened, and your warranty will be invalid. Damage through damp Do not use the instrument in damp environments! The instrument can be permanently damaged by the penetration of water.
Basics Accessories Accessories available for the MR2 / MR-PRO: • Pouch MR2 / MR-PRO NTI Art.No 600 000 302 • The soft pouch protects the Minirator against shock and dust and comes with a convenient belt-clip. • System Case EU Power Supply 7.5V NTI Art.No 600 000 311 The Cable Test Adapter is used for single-ended cable testing. By installing the Cable Test Adapter at the far end of the cable, the MR-PRO will be able to complete its cable test procedure and display the condition. NTI Art.
Overview 2.
Overview Buttons and operating elements 1 2 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 and a flashing mute button. wave freq level sens 8 The button lights up continually during the pauses of the “PNoise” and “Chirp” signal waveforms.
Overview The screen display Settings for signal generation The main menu 1 2 1 2 3 4 7 4 5 6 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.
Overview Display of the measured values (MR-PRO) 1 2 3 1 2 3 10 Phantom voltage Balance Impedance
Overview Power supply Battery operation In order to be always able to use the Minirator flexibly, we recommend the use of batteries. 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: Only use 3x AA, LR6 batteries. The battery consumption increases at higher level setting as well is based on the connected load. During operation, the battery temperature may increase noticeably. This is not a defect.
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. MR2 outputs Both the RCA and the XLR have a balanced output impedance of 200 Ohm.
Overview MR-PRO outputs Both the RCA and the XLR have a balanced output impedance of only 12.5 ohms. The level of the XLR output corresponds closely to the set output voltage, based upon the low 12.5 ohm output impedance of the generator. MR-PRO I<10mA ~ U/2 U ~ U/2 RCA 6.3 Ω XLR short-circuit between Pin 1 and 3 Commercially available XLR to RCA adapters short-circuit the XLR Pins 1 and 3.
Getting Started 3. Getting Started Inserting the batteries Only use batteries from the same manufacturer. Replace the discharged batteries by new ones. Do not mix used and new 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 14 You have now successfully inserted the batteries.
Getting Started Fitting the protective shock jacket (MR-PRO only) With the MR-PRO, you can fit the supplied protective shock jacket. This will protect the instrument against light impacts without impairing its easy operation. 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 fitted the protective shock jacket Damage through impacts / shocks 1. 2.
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 fit the hand strap when the protective shock jacket of the MR-PRO has been fitted. 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 1. You have now secured the hand strap. 2. 3.
Getting Started Connecting the Minirator 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 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. You have now connected the Minirator.
Operation 4. Operation Switching the Minirator on and off Navigation in the menu bar Switching the Minirator on The menu bar is divided into two parts. On the left-hand side, you can choose between the Generator, Cable test (MR-PRO only), Impedance (MR-PRO only) and System functions. 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.
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. 1. Ensure that GENERATOR 1 is selected in the menu bar. 2. Select “WAV” 2 with the rotary wheel. 3. Press “Enter”. C A selection menu appears. Signal selection using the direct buttons 1. Ensure that GENERATOR 1 is selected in the menu bar. 2. Press the “Wave” button. C 4. Select the desired test signal with the rotary wheel. 5. Press “Enter”.
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 rotary wheel 1. Turn the rotary wheel. C The selected parameters will be marked with a black bar. 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.
Operation 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. C The current sensitivity of the rotary wheel will be displayed 1 . 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.
Operation System settings You can adjust various system settings of your instrument. To do this, switch to System 1 in the menu bar using the rotary wheel and confirm with “Enter”. 3. Turn the rotary wheel to set the desired time. 4. Confirm the entry with the “Enter” button. C The possible system settings are displayed: You have now changed the switch-on time of the Power-Save mode.
Operation Configurations (MR-PRO only) Firmware Display of the version number, with the possibility of carrying out an update for the MR-PRO 4 (see “Update instrument” chapter). With the MR-PRO, you can store your current instrument settings as configurations, and can call these up again at a later date. Storing configurations 10 configuration storage locations are available to you. Display of the serial number You can read out the instrument’s serial number bottom line.
Operation C You have now stored the current instrument settings as a configuration. Calling up configurations 1. Use the rotary wheel to select CONFIG in the menu bar. 2. Confirm with “Enter”. C Transferring configurations to another device (MR-PRO) With the MR-PRO, you have the possibility of transferring stored configurations to another device. 1. Connect your MR-PRO to a computer via USB. C The following menu is opened: A removable memory drive will be indicated on the computer. 2.
Test signals 5. The Minirator Test Signals Sine Sweep 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. Characteristics and use Sweep signals with a resolution of up to 1/12 octave can be generated over a freely selectable frequency range.
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 define 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 configure the signal sequence here.
Test signals Chirp Once-only : Plays the test signal once. Continuous : Repeats the test signal after an adjustable pause (tPAUSE). Parameters You can define 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.
Test signals Delay Test 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. Characteristics and use The Delay Test signal is a specially configured Chirp signal.
Test signals Pink Noise 1 2 Characteristics and use The Pink Noise test signal has a high spectral density, an infinite 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. Operation You can choose between the following test signal modes with the MOD setting 1 : CONT : generates a continuous test signal.
Test signals White Noise Polarity Characteristics and use The White Noise test signal has a high spectral density, Gaussian amplitude distribution and an infinite 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. Characteristics and use The sawtooth test signal is ideally suited for checking the polarity of loudspeakers.
Test signals 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 files are organized in sub-folders. The MR-PRO is already equipped with a series of demo sequences in the WAV file format. You can create a link to a computer at any time via the USB interface and can exchange existing WAV files or add new ones.
Test signals Loading your own WAVE files Wave files for the MR-PRO must fulfill the following requirements: • • • 2. Open the “WAVE” sub-folder on the removable medium 48 kHz sampling frequency Mono / Stereo 16-bit definition All the sub-folders in the “Wave” folder now appear in the folder selection 1 . Add additional sub-folders to this folder level as required. If a Wave file does not meet the requirements, the playback stops and the “Mute” button lights up continuously red.
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 files from the MR-PRO onto your computer or delete unnecessary files. 4. Copy the desired files into the folder. C You have now loaded your Wave files. Parameters You can define the following parameters for this test signal: Output level The output level of this test signal is adjusted in dBF (dB full scale) or %.
Meas. functions (MR-PRO only) 6. The Measurement Functions of the MR-PRO The MR-PRO offers the following measurement functions: Menu Measurements Generator Impedance Phantom Power Balance Cabletest XLR cables Phantom Power Impedance Impedance + Phase Apparent Power + Phase Phantom Power Balance Impedance test in generator mode The MR-PRO measures phantom voltages and displays impedances and the impedance balance in the SINEWAVE operating mode.
Meas. functions (MR-PRO only) MR-PRO Balance display RCA 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. 2 R2 1 R3 3 Balanced impedance, R2 = R3 XLR Unbalanced impedance, R3 > R2 The impedance and balance measurement can only be carried out down to a defined minimum level.
Meas. functions (MR-PRO only) Measuring phantom power 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. Mixing desk MR-PRO +48V 2 x 6.8k 2 V2 R2 1 V3 1 R3 3 XLR The most common phantom voltage is 48 V and lies on both Pin 2 and Pin 3 with balanced impedances (see diagram).
Meas. functions (MR-PRO only) XLR cable test The MR-PRO supports a cable test function that quickly detects damaged XLR cables. To test a cable, proceed as follows: 2. The cable test is based on an impedance measurement. In order to indicate a correctly wired XLR cable, the test routine of the MRPRO assumes the following impedances on the output: MR-PRO MR-PRO or adapter 2 Cable 1. R2 = 1k 1 R3 = 2k 3 XLR Out XLR In 1. Select the “Cable test” function in the menu. 2.
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 pins 2 and 3 are crossed. Other error indications may appear depending on the cables fault. The tested cable is OK. 38 For long cables already in place, NTI offers an optional adapter named “Cable Test Plug”. Plug one end of the cable into the Cable Test Plug and the other end of the cable into the MR-PRO.
Meas. functions (MR-PRO only) Impedance test The impedance test supports the verifications of distributed loudspeaker installations and shows detailed information of the connected load. Supported Display Modes 1 Connect any unpowered load between Pin 2 + 3 of the XLR output for best performance. 2 Damage caused by high voltage Never connect the instrument to a power output or any activated distribution system! In the mode |Z| + Phase and the phase is shown.
Meas. functions (MR-PRO only) Power indication Impedance 2 1 1 3 2 3 How to measure 1. Connect the load between Pin 2 + 3 of the XLR. 2. The absolute value of the impedance 1 , the phase 2 and whether the load is inductive or capacitive 3 is displayed. How to measure 1. Select the reference voltage of the distributed loudspeaker system 1 with the rotary wheel. 2. Connect the load between Pin 2 + 3 of the XLR. 3. The apparent power 2 in VA (Volt Ampere) and the phase information 3 is displayed.
Updating the instrument 7. Updating the Instrument General firmware update: Updating the firmware You can find the installed firmware version of your instrument as follows: Please follow the instructions below: 1. Select “System” in the menu bar. 2. Confirm the selection with the “Enter” button. C The firmware version of the instrument will be displayed. The firmware revision history is listed on our website at http://support.nti-audio.com/mr2.
Trouble shooting 8. Tips and Trouble Shooting Calibration Resetting to the factory settings The Minirator has been carefully tested during production and corresponds to the specifications listed in the “Technical Data” chapter. If the Minirator reacts unexpectedly, a reset to the factory settings might solve the problem. NTI recommends regular calibration of the instrument in annual intervals.
Trouble shooting Faults and their correction Fault Fault finding The Minirator does not gener- “Mute” button blinks. ate an output signal. “Mute” button lights up continuously. Screen contrast poor. Cause Remedy You have switched the instrument to Mute. Press the “Mute” button. You have called up the “Pink Noise” (PNoise) test signal or you are in the Pause cycle of the Chirp test signal. Wait until the pause has ended. Non-supported Wave format. Load a supported Wave format.
Technical data 9. Technical Data MR2 Outputs MR-PRO Balanced XLR, unbalanced RCA phantom power resistant Inputs DC power supply, USB DC power supply, USB XLR for cable test Signal Wave Forms Sine, Polarity Test Signal, Delay Test Signal, White Noise (crest factor = 3.05), Pink Noise (crest factor = 4.
Technical data THD+N 22 Hz - 22 kHz, average, @ 1 kHz, typical Output Impedance Impedance Measurement MR2 MR-PRO -90 dB (0.0032%) @ 8 dBu, Noise floor typ. 25 μV -96 dB (0.0016%) @ 18 dBu, Noise floor typ. 15 μV 200 Ohm (balanced) 12.5 Ohm balanced, Imax = 10 mA Method: Meas. range: 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 Accuracy: Power Calculation Reference voltage Phantom Voltage Meas.
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.
Further information Declaration of Conformity Information regarding disposal CE / FCC Compliance Statement and recycling 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 Dispose of your instrument in accordance with the valid legal environmentally regulations in y
