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Hardware Configuration
Hydrophone with a Built-in Preamp (9m)
XLR-to-USB Converter
Hardware Configuration
Hydrophone with a Built-in Preamp (6m)
XLR-to-USB Converter
Both VT USA-168A and VT USA-168B are high-sensitivity low-noise PC based USB 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.
Find out more: Manual
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.
| General | USA-168A | USA-168B |
|---|---|---|
| Frequency Range | 20Hz ~ 4kHz (± 4dB) | 20Hz ~ 10kHz (± 5dB) |
| Sound Level Measurement Range |
48dB ~ 161dB (typical) (Old Version: 63dB ~176dB) |
59dB ~ 172dB (typical) (Old Version: 75dB ~ 188dB) |
| Useful Frequency Range | (<10Hz) ~ (>100kHz) (Sensitivity drops about 45dB @100kHz) | (<10Hz) ~ (>100kHz) (Sensitivity drops about 44dB @100kHz) |
| Operating Depth | <80m | |
| Sampling Rate | 44.1kHz, 48kHz, 88.2kHz, 96kHz | |
| Bit Depth | 24 bit | |
| Number of Input Channels | 1 | |
| Direct Monitoring without Passing Through Computer | Supported | |
| Frequency Accuracy | 0.01% | |
| Frequency Weighting | Flat, A, B, C, ITU-R 468 | |
| Time Weighting |
Linear, Exponential (Equivalent continuous sound level (Leq) fully complies with IEC61672) |
|
| Octave Analysis |
1/1,1/3,1/6,1/12,1/24,1/48, 1/96 (Complies with IEC61260) |
|
| Other Functions | Much more functions are described in the software manual. | |
| USB interface | USB 2.0, driver installation required | |
| Input Isolation | No (Isolation can be achieved through a USB high speed isolator) | |
| Power Source | USB bus power (Type B), DC 5V power supply (Micro-B), or 2xAA batteries | |
| Power Consumption | Max. 5W | |
| System Requirements |
Windows 10/11, 32 bit or 64 bit. Minimum Screen Resolution: 1024 x 600 |
|
| Calibration | Not calibrated individually. Nominal value is used instead. Not recommended for absolute sound level measurement. | |
| General | USA-168A | USA-168B |
|---|---|---|
| Transducer Type | Plate bender | Dual plate benders, mechanically balanced |
| Frequency Range | 20Hz ~ 4kHz (± 4dB) | 20Hz ~ 10kHz (± 5dB) |
| Sensitivity | -165dB re: 1 V/μPa (Typical) (Old Version: -180dB) |
-176dB re: 1 V/μPa (Typical) (Old Version: -192dB) |
| Useful Frequency Range | (<10Hz) ~ (>100kHz) (Sensitivity drops about 45dB @100kHz) |
(<10Hz) ~ (>100kHz) (Sensitivity drops about 44dB @100kHz) |
| Size | ϕ25mm x 46mm | ϕ17mm x 32mm |
| Weight | 105g | 10g |
| Specific Gravity | 5.3 | 1.3 |
| Added Weight | Not required | 150g |
| With Built-In Preamp | Yes | |
| Polar Response | Omnidirectional (horizontal) | |
| Connector | XLR (pin 1: ground, pin 2: hot, pin 3: unused) | |
| Power Supply | 48V Phantom | |
| Power Consumption | 1.2 mA (Typical) | |
| Mic/Hi-Z | |
|---|---|
| Connector | XLR/TS combo jack |
| Full-Scale Input Voltage Range | Mic: ±0.006V ~ ±0.9V; Hi-Z: ±0.005V ~ ±3.5V Adjustable through the GAIN knob |
| Input Impedance |
Mic: 1.8kΩ (unbalanced), 3.6kΩ (balanced) Hi-Z: 484kΩ |
| Analog Line In | |
| Connector | ϕ3.5mm stereo jack |
| Full-Scale Input Voltage Range | ±1.2V |
| Input Impedance | 22kΩ |
| Analog Output L/R | |
| Connector | RCA (coaxial) |
| Full-Scale Output Voltage Range | ±0.02V ~ ±0.9V, adjustable through the OUTPUT knob |
| Output Impedance | 1kΩ |
| Phones | |
| Connector | ϕ3.5mm stereo jack |
| Full-Scale Output Voltage Range | ±0.01V ~ ±1.8V, adjustable through the OUTPUT knob |
| Output Impedance | 10Ω |
| Other Specifications | |
| Frequency Response | 10Hz~40kHz, ±2dB |
| Size | 119.2 mm (L) x 91.8 mm (W) x 44.6 mm (H) |
| Weight | 151g |
