Aquarian Audio Products H3 Manual del usuario

Navegue en línea o descargue pdf Manual del usuario para Teléfono Aquarian Audio Products H3. Aquarian Audio Products H3 2 páginas. Hydrophone

Thank you for purchasing your Aquarian Audio Products H3 hydrophone. The H3 uses a unique high-

sensitivity, dual-sensor, mechanically-balanced transducer assembly that offers exceptional signal-to-noise

performance in the human auditory bandwidth. The fully-shielded design inherently rejects EMI and RFI noise,

making it useful in the studio, lab or shop. Its low mass and full polyurethane rubber encapsulent makes it highly

resistant to damage caused by impact. Its small size allows users to fish it inside of pipes and other tight spaces,

making it excellent for leak monitoring. Though designed primarily for underwater listening, it is also useful as a

waterproof microphone for tool room applications, such as monitoring cutting in waterjet and other CNC tooling.

Using the H3

The H3 is sold in two primary configurations and can be purchased with various options for output

connectors:

H3 and H3b are passive devices. The standard configuration is terminated with a 1/4" TS plug, making it

compatible with many high-impedance audio devices, such as guitar amplifiers or computer sound interfaces. The

"b" configuration is terminated with a standard male BNC connector, useful for connecting to various test and

measurement equipment. Each of these require a high-impedance amplifier to maximize bandwidth and minimize

noise. 50 to 60 dB of adjustable gain is useful for common audio applications.

Input Impedance is the amount of load that your preamp puts on the hydrophone. The low-frequency response of

a piezo transducer, such as that used in the H3, will be limited by the input impedance of the preamp. Higher input

impedance will give you an extended low-frequency response. This relationship can be calculated for the H3 with

the following formula:

Fc is the frequency at which electrical output is 3dB below nominal and R is the input impedance of your preamp.

Therefore, using a preamp with an input impedance of approximately 500 KΩ will give you a low-frequency cutoff

of 20 hertz—the low end of what humans can hear. Many high-impedance audio preamps have input impedances

of 1MΩ or more. Test equipment, such as oscilloscopes and spectrum analyzers have typical input impedances of

10MΩ or more.

H3m and H3x configurations include an impedance buffer amp that is built into the hydrophone, which make them

compatible with standard consumer and professional microphone circuits. The "m" configuration is terminated with

a 3.5mm "mini" stereo (TRS) plug that is wired with the tip and ring shorted. This is compatible with nearly all

consumer microphone circuits, such as those used in hand-held recorders, computer sound interfaces, and many

video devices. Plug-in-power (PIP) is required and may need to be switched on in your device.

The "x" configuration is terminated with a standard (full-sized) XLR male connector. These are typically used in

professional-quality mic preamps, including those built into digital recorders and PA systems. Phantom power is

required and may need to be switched on in your device. Any common phantom voltage will work.

Please note that the H3x is a single-ended output. The XLR connector is a 3-pin device that is typically used for

balanced transmission lines. Pin 1 is typically ground, pin 2 carries the signal. Pin 3 most often carries an inverted

signal, but in all balanced cables has an signal impedance that is equal to Pin 2. Receiving circuitry in the preamp

then cancels signals that are common to both lines—primarily electrical noise induced into the cable. With the

H3x, pin 3 is left unconnected. It is a simple output plug variation of the H3m that takes advantage of the very wide

bias supply range of the included buffer amp. This single-ended configuration saves power and complexity and

works well with nearly all microphone inputs. The hydrophone is very well shielded and common-mode noise is not

really an issue in most hydrophone applications. If you have one of the few recorders or mic preamps that will not

tolerate a single-ended load well, we recommend buying the H3b and using the Aquarian PA4 preamp.

Aquarian Audio Products

H3 Hydrophone User's Guide

Fc = 1 / 0.000000094 * R