{"id":800,"date":"2025-05-26T11:02:23","date_gmt":"2025-05-26T02:02:23","guid":{"rendered":"https:\/\/acoustic-measurement.com\/?post_type=technology&p=800"},"modified":"2025-05-26T11:02:24","modified_gmt":"2025-05-26T02:02:24","slug":"soundintensityprobe","status":"publish","type":"technology","link":"https:\/\/acoustic-measurement.com\/en\/technology\/soundintensityprobe\/","title":{"rendered":"Acoustic Intensity Probe"},"content":{"rendered":"\n

An acoustic intensity probe consists of two microphones mounted face-to-face with a spacer positioned between them.
This configuration has been found to offer better frequency response and directional characteristics compared to side-by-side, back-to-back, or face-to-face arrangements without a spacer.<\/p>\n\n\n\n

There are three types of spacers available \u2014 6 mm, 12 mm, and 50 mm \u2014 which maintain a fixed distance between the microphones.
The choice of spacer depends on the frequency range to be covered.<\/p>\n\n\n\n

Directivity Characteristics<\/h2>\n\n\n\n

The directivity pattern of an acoustic intensity analysis system appears as a figure-eight shape in a planar view, which is referred to as a cosine characteristic.
This characteristic arises from the design of the probe and the calculations performed by the analyzer.<\/p>\n\n\n\n

Since sound pressure is a scalar quantity, transducers used for sound pressure measurement must respond equally to sound from all directions \u2014 that is, they must be omnidirectional.
In contrast, acoustic intensity is a vector quantity.
With a two-microphone probe, the system does not measure the full vector but instead measures the single directional component along the axis of the probe.<\/p>\n\n\n\n

A complete vector is composed of three mutually perpendicular (90\u00b0 to each other) components, one for each coordinate axis.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

When sound is incident at a 90\u00b0 angle relative to the probe axis, there is no difference between the sound pressure signals from the two microphones.
As a result, there is no component along the probe axis, the particle velocity becomes zero, and thus the acoustic intensity also becomes zero.<\/p>\n\n\n\n

In contrast, when sound is incident at an arbitrary angle \u03b8 relative to the axis, the intensity component along the axis decreases by a factor of cos\u03b8.
This reduction leads to the cosine directivity characteristic of the probe.<\/p>\n","protected":false},"excerpt":{"rendered":"

An acoustic intensity probe consists of two microphones mounted face-to-face with a spacer positioned between them.This configuration has been found to offer better frequency response and directional characteristics compared to side-by-side, back-to-back, or face-to-face arrangements without a spacer. There are three types of spacers available \u2014 6 mm, 12 mm, and 50 mm \u2014 which […]<\/p>\n","protected":false},"featured_media":0,"parent":0,"template":"","solution_cat":[2],"class_list":["post-800","technology","type-technology","status-publish","hentry","solution_cat-tax_power","en-US"],"acf":[],"_links":{"self":[{"href":"https:\/\/acoustic-measurement.com\/wp-json\/wp\/v2\/technology\/800","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/acoustic-measurement.com\/wp-json\/wp\/v2\/technology"}],"about":[{"href":"https:\/\/acoustic-measurement.com\/wp-json\/wp\/v2\/types\/technology"}],"wp:attachment":[{"href":"https:\/\/acoustic-measurement.com\/wp-json\/wp\/v2\/media?parent=800"}],"wp:term":[{"taxonomy":"solution_cat","embeddable":true,"href":"https:\/\/acoustic-measurement.com\/wp-json\/wp\/v2\/solution_cat?post=800"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}