Virtins technology VT USA-168A User manual

VT USA-168A/B Real Time Underwater Sound Analyzer Manual Rev. 1.5
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VT USA-168A/B Real Time Underwater Sound Analyzer
Manual
Note: VIRTINS TECHNOLOGY reserves the right to make modifications to this manual at any time without
notice. This manual may contain typographical errors.

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TABLE OF CONTENTS
1 INSTALLATION AND QUICK START GUIDE..........................................................................................3
1.1 PACKAGE CONTENTS....................................................................................................................................3
1.2 HARDWARE CONNECTION ............................................................................................................................4
1.3 HARDWARE DRIVER INSTALLATION.............................................................................................................5
1.4 MULTI-INSTRUMENT SOFTWARE INSTALLATION AND CONFIGURATION.......................................................6
1.4.1 Install Multi-Instrument.......................................................................................................................6
1.4.2 Start Multi-Instrument..........................................................................................................................6
1.4.3 Configure Multi-Instrument.................................................................................................................8
1.5 INPUT OF SOUND LEVEL CALIBRATION DATA AND ADJUSTMENT OF INPUT GAIN......................................12
1.5.1 Under Windows 8/8.1/10/11 ..............................................................................................................13
1.5.2 Adjustment of Input Gain via Hardware Gain Knob .........................................................................15
1.5.3 0dB Reference Vr...............................................................................................................................15
1.6 MOST FREQUENTLY USED MEASUREMENT SETTINGS ................................................................................16
1.7 USING HYDROPHONE WITH BATTERIES OR AN EXTERNAL POWER SUPPLY WITHOUT A COMPUTER...........16
1.8HYDROPHONE MAINTENANCE....................................................................................................................17
1.9SLIDING STAINLESS STEEL WEIGHT ON VT USA-168B .............................................................................17
1.10 USING VT USA-168A AS A CONTACT MIC ANALYZER IN AIR.................................................................17
1.11 CONNECTING HYDROPHONES TO 3.5MM TRS MIC INPUT OF OTHER AUDIO DEVICES..............................18
2 SPECIFICATIONS.........................................................................................................................................19
2.1 VT USA-168A/B OVERALL HARDWARE SPECIFICATIONS.........................................................................19
2.2HYDROPHONE SPECIFICATIONS ..................................................................................................................19
2.3 XLR-TO-USB SOUND CARD ......................................................................................................................20
2.4MULTI-INSTRUMENT SOFTWARE SPECIFICATIONS......................................................................................22
3 MULTI-INSTRUMENT SOFTWARE LICENSE INFORMATION ........................................................31
3.1 LICENSE TYPES...........................................................................................................................................31
3.2 LICENSE UPGRADE FROM ONE LEVEL TO ANOTHER...................................................................................31
3.3 SOFTWARE UPGRADE IN THE SAME LICENSE LEVEL...................................................................................31
4 WARRANTY...................................................................................................................................................31
5 DISCLAIMER.................................................................................................................................................32

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1 Installation and Quick Start Guide
Both VT USA-168A and VT USA-168B are high-sensitivity low-noise real-time underwater
sound analyzers in the human auditory range. They are equipped with high-sensitivity
hydrophones with built-in preamps and XLR output connectors, which are compatible with
the common phantom powered XLR interface. The hydrophones can withstand a static water
pressure up to 80m and drive a cable up to 250 m with negligible signal degradation.
The hydrophone of VT USA-168A is rugged and compact. Its small, streamlined shape and
high specific gravity will help maintain a low working depth in mild wind and currents. Its
compact size and flexible cable make it very portable and simple to use.
The hydrophone of VT USA-168B uses a unique high-sensitivity, dual-sensor, mechanically-
balanced transducer assembly that offers exceptional signal-to-noise performance. Compared
with the hydrophone of VT USA-168A, it has a smaller size and much lower specific gravity
and thus can be inserted into pipes and other tight spaces, making it excellent for leak
finding. Its low mass and full polyurethane rubber encapsulant make it highly resistant to
damage caused by impact. To maintaining negative buoyancy underwater, it is assembled
with a 150g sliding stainless steel weight on the cable. Though designed primarily for
underwater listening and leak finding, it is also useful as a waterproof microphone for tool
room applications, such as monitoring cutting in waterjet and other CNC tooling.
Both VT USA-168A and VT USA-168B have not been individually calibrated although the
nominal values are provided, their use in absolute sound level measurement is thus not
recommended (Please check our other products instead).
1.1 Package Contents
A standard VT USA-168A/B Package contains the following items:
1) Hydrophone with a built-in preamp and integrated XLR cable
Or
(USA-168B)
(USA-168A) or (USA-168B)
(default cable length: 9 m) (default cable length: 6 m)
Note: USA-168A has a thread-mount version of hydrophone on request. 1/4" NPT (National Pipe Thread) with
7/16" (12mm) wrench flats. Standard configuration includes 1/2-meter cable with stripped and tinned wire
termination.
2) XLR-to-USB Sound Card

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3) USB 2.0 Cable (1.5m)
4) CD (containing the copy-protected Multi-Instrument software)
The latest software can always be downloaded from www.virtins.com/MIsetup.exe.
5) USB hardkey (containing a Multi-Instrument Pro license)
6) Carrying Case
1.2 Hardware Connection
Connect the hydrophone to the Mic/Hi-Z jack of the XLR-to-USB sound card.

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Then connect the XLR-to-USB sound card to the PC’s USB port using the supplied USB
cable.
Switch the POWER SOURCE to USB. The red POWER LED should light up indicating that
it is receiving power. Then switch on the 48V phantom power to supply power to the built-in
preamp of the hydrophone.
The USB hardkey needs to be plugged into any USB port of the PC in order to activate the
Multi-Instrument software. Otherwise the software will run under the 21-day fully functional
free trial mode before the trial period expires.
1.3 Hardware Driver Installation
The device driver installer USA168_DriverInstaller.exe is located in the Drivers\VTUSA168
directory in the CD. When you install the Multi-Instrument software, a copy of the device
driver installer will also be installed in the software installation
directory\Drivers\VTUSA168. Run it to install the driver. After driver installation, the
device will be supported by both sound card MME and ASIO drivers in Multi-Instrument.

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1.4 Multi-Instrument Software Installation and Configuration
Multi-Instrument is a powerful multi-function virtual instrument software. It supports a
variety of hardware ranging from sound cards which are available in almost all computers to
proprietary ADC and DAC hardware such as NI DAQmx cards, VT DSOs and so on. It
consists of multiple test instruments such Oscilloscope, Spectrum Analyzer, and Multimeter,
etc.
1.4.1 Install Multi-Instrument
Insert the Multi-Instrument installation CD into your computer’s CD-ROM drive and follow
the instruction on the screen to install the Multi-Instrument software. The installation file
can also be downloaded from www.virtins.com/MIsetup.exe.
1.4.2 Start Multi-Instrument
To start Multi-Instrument, on the Windows desktop, select [Start]>[All Programs]>[Multi-
Instrument]>[VIRTINS Multi-Instrument], or simply double click the MI icon.
If the software is started for the very first time after installation, it will prompt the user to
select a default device (see figure below). Select VT USA-168A or VT USA-168B according
to the hardware device to be used.

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The default device can also be changed later via [Setting]>[ADC Device], [Setting]>[DAC
Device], and [Setting]>[Configure Hot Panel Setting Toolbar], or simply [Setting]>[Restore
to Factory Default]. However, if [Restore to Factory Default] command is executed, all
calibration data entered manually via [Setting]>[Calibration] after software installation
will be reset to the default values of the selected product. To avoid the loss of the
manually entered calibration data, you can save them as a calibration file first.
Otherwise, you will have to enter the unique calibration data that come with the
product package again.
In case the driver has not yet been installed, the software will prompt the user to install the
driver. Restarting program is required after that.
After the default device is selected, the software will prompt the user to select a default color
scheme (Skin). The default skin can also be changed later via [Setting]>[Display].

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The main window of the software will open after the above skin selection. The following
figure shows a typical screen layout (obtained by clicking the “OCT3” button in the Hot
Panel Setting Toolbar after the launch of the software). Please refer to the software manual
for detailed functions of the software. The software manual can be accessed via [Start]>[All
Programs]>[Multi-Instrument]>[VIRTINS Multi-Instrument Manual] (in PDF format) or
[VIRTINS Multi-Instrument Help] (in HTML format) on Windows Start menu, or
[Help]>[Software Manual] or F1 inside the software.
1.4.3 Configure Multi-Instrument
In Multi-Instrument, the menu items are enabled / disabled based on context. Many menu
items are disabled when the Oscilloscope or the Signal Generator is running. To do the
configuration, stop the oscilloscope first by pressing the green button at the upper left corner
of the screen (see figure below). The button will turn red once the Oscilloscope is stopped.
1.4.3.1 Configure Sound Recording Devices for Multi-Instrument
The XLR-to-USB sound card can be used with either MME or ASIO driver. ASIO driver is
recommended as it uses the sampling rate selected in Multi-Instrument directly and bypasses

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the possible sampling rate conversion and audio signal enhancement by Windows, which
may otherwise alter the original samples and lead to measurement inaccuracies.
1.4.3.1.1 Using ASIO Driver
Go to [Setting]>[ADC Device], and select “Sound Card ASIO”in the “Device Model”field.
Then choose “Zoom U-22 ASIO Driver” in the “Device No.” field (see figure below). This
is to configure the XLR-to-USB sound card as the sound recording device for the software.
Now, if you start the oscilloscope by pressing the red button at the upper left corner of the
screen, and then talk LOUDLY before the hydrophone, you should be able to see your
“voices” in the Oscilloscope and Spectrum Analyzer.
1.4.3.1.2 Using MME Driver
Go to [Setting]>[ADC Device], and select “Sound Card MME”in the “Device Model”field.
Then choose “Line (ZOOM U-22 Audio)” in the “Device No.” field (see figure below). This
is to configure the XLR-to-USB sound card as the sound recording device for the software.
Note that the displayed name of the sound card may vary a bit under different Windows
versions or with different USB ports.

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Now, if you start the oscilloscope by pressing the red button at the upper left corner of the
screen, and then talk LOUDLY before the hydrophone, you should be able to see your
“voices” in the Oscilloscope and Spectrum Analyzer.
Some Windows versions / editions come with some audio signal enhancement features which
are enabled by default. These features must be disabled through the Sound Recording Control
under Windows Control Panel to prevent them from altering the originally sampled data, as
shown below. One of the possible problems caused by these features is the unwanted
alteration of the frequency response of the setup. Using ASIO driver instead of MME driver
can avoid these problems. It should also be noted that when MME driver is used, the actual
sampling rate is determined by the sampling rate configured in the Sound Recording Control
Panel (see figure below). If the sampling rate selected in Multi-Instrument differs from the
actual one, then sampling rate conversion will be performed automatically by Windows and
this will alter the original data unwantedly.
1.4.3.2 Configure Sound Playback Devices for Multi-Instrument
The Signal Generator of Multi-Instrument can be used for sound playback and generation.
You can use it to playback a recorded underwater sound, or generate an underwater test
sound if you have an underwater sound emitter attached. To configure the sound card for the
Signal Generator, go to [Setting]>[DAC Device]. Either “Sound Card MME” or “Sound
Card ASIO” can be chosen in the “Device Model” field. Choose the corresponding sound
card’s name in the “Device No.” field. By default, the XLR-to-USB sound card with its
ASIO driver is selected for signal output.