Calibration of the pressure sensitivity of microphones by a free-field method at frequencies up to 80 khz.

Free-field calibration of the pressure sensitivity of microphones at frequencies up to 80 kHz

The Phone-Or 3D Optical Energy Density Probe: calibration test report of the modified/re-calibrated probe

This report discusses the results from the second calibration test performed on the Phone-Or 3D optical Energy Density probe. The first calibration test found several performance issues associated with high level of noise in the Phone-Or probe. Since then, the Phone-Or manufacturer has addressed those issues by modifying and re-calibrating the probe. To investigate the current performance of mo...

A time-selective technique for free-field reciprocity calibration of condenser microphones.

In normal practice, microphones are calibrated in a closed coupler where the sound pressure is uniformly distributed over the diaphragm. Alternatively, microphones can be placed in a free field, although in that case the distribution of sound pressure over the diaphragm will change as a result of the diffraction of the body of the microphone, and thus, its sensitivity will change. In the two ca...

Sound pressure distribution and power flow within the gerbil ear canal from 100 Hz to 80 kHz.

Sound pressure was mapped in the bony ear canal of gerbils during closed-field sound stimulation at frequencies from 0.1 to 80 kHz. A 1.27-mm-diam probe-tube microphone or a 0.17-mm-diam fiber-optic miniature microphone was positioned along approximately longitudinal trajectories within the 2.3-mm-diam ear canal. Substantial spatial variations in sound pressure, sharp minima in magnitude, and h...

Design and fabrication of an ultrasonic thermoacoustic generator using metal nanocoatings (Research Article)

In this paper, we design, simulate, and build an ultrasonic heat generator. In thermoacoustics, heat generated by the passage of alternating current through a thin conductor produces a sound wave. In this method, unlike other methods of sound production, moving parts are not used to vibrate air molecules, and as a result, the frequency response of these generators is flatter than other sound ge...