Acoustic Probe

Acoustic Probe

 

a device for measuring the sound pressure at a given point in a sound field, it ensures minimum distortion of the field by the measurement process. An acoustic probe usually consists of a narrow wave guide connected to an acoustic receiver. The end of the wave guide is inserted into the area of the sound field being studied. Depending on the conditions of measurement, the wave guide may be a tube containing a column of gas or fluid or a solid rod that is insulated from the surrounding medium—for example, by a gas jacket. The acoustic insulation of the wave guide guarantees that only the energy from the test area of the field reaches the receiver. Special measures are taken to eliminate resonance phenomena and produce a traveling wave in acoustic probes. Thus, in probes designed for operation in air over the audible frequency range, the metal guide tube is connected to a rubber tube of the same diameter fIIIed with a sound-absorbing material to increase attenuation. The acoustic receiver, a microphone, is mounted on the side close to the tubing joint.

In acoustic probes for the ultrasonic range, the wave guides are solid metal coated on the outside with a sound-absorbing material; the acoustic receivers are plates or cylinders made from a piezoelectric ceramic.

REFERENCES

Bergmann, L. Ul’trazvuk i ego primenenie v nauke i tekhnike, 2nd ed. Moscow, 1957. (Translated from German.)
Beranek, L. Akusticheskie izmereniia. Moscow, 1952. (Translated from English.)
Mentioned in ?
References in periodicals archive ?
This is done by the insertion of an acoustic probe into the top of the tank at a few locations depending on the size of the tank.
Flow regimes in a horizontal hydrotransport pipe can be determined from acoustic probe measurements and frequency and cycle analysis techniques.
Acoustic probes were located along the length of the pipe and signals were acquired at 40 000 Hz.
Berruti, "Flow Regime Detection in Horizontal Pneumatic Transport of Fine Powders using Non-Intrusive Acoustic Probes," Powder Technol.
Book, "Flow Regime Determination in Upward Inclined Pneumatic Transport of Particulates using Non-Intrusive Acoustic Probes," Chem.
Single-point measurement with the 3D acoustic probe.
Although you cannot see it in Figure 2, there is a small dot atop of the base of the acoustic probe.
Typically, we use the toe-in angle of a speaker as a method to shape the soundstage, but I found that the Trinnov was not at all happy if I did not point the speaker directly at the acoustic probe with about 5 degrees of wiggle room.
Wherever you aim the dot on the acoustic probe, that is the direction the processor will place the center image.
NACOA participants displayed normal startle response patterns, initially characterized by increased EMG and SCOR to acoustic probes of increasing intensity.
The submunition deployed its flight surfaces (tails and wings) and acoustic probes, and glided toward the column, homing on the sound of the moving vehicles.

Full browser ?