Typical reverberant chambers used for High Intensity Acoustic Testing (HIAT) can achieve high sound pressure levels (SPL) across most of the applicable frequency range (20 Hz to 10 kHz), but they have limitations. Depending on the size of the chamber, low frequency chamber modes may be limited in the testing frequency range. In addition, reverberant chambers that use conventional 1/3-Octave controllers are not able to control low frequency chamber modes as effectively as the higher frequencies. A typical response to this inability to control the chamber modes is to high pass the frequency range of the excitation in the chamber to prevent exciting the low frequency modes. This method protects the test article from over-testing, although it also might under-test an article that has a fundamental mode below the high-pass frequency of the chamber. Recently, Maryland Sound International conducted a test at the Naval Research Laboratory (NRL) to determine if Direct Field Acoustic Testing (DFAT) technology could be applied to conventional reverberant chambers.

This content is only available as a PDF.
You do not currently have access to this content.