Measurement Of The Diffraction Correction Of The Gulton Model P420m-6 Microphone

Item

Title
Measurement Of The Diffraction Correction Of The Gulton Model P420m-6 Microphone
Date
1967
Index Abstract
Coming Soon
Photo Quality
Complete
Report Number
AFFDL TR 66-223
Creator
Ortega, Jose C.
Corporate Author
Western Electro-Acoustic Lab Inc Santa Monica CA
Laboratory
Flight Dynamics Laboratory
Extent
42
Identifier
AD0816179
Access Rights
Export controls
Distribution Classification
1
Contract
AF 33(615)-3746
DoD Project
1472
DoD Task
147203
DTIC Record Exists
No
Distribution Change Authority Correspondence
AFFDL LTR
Abstract
The methods and instrumentation used to obtain the diffraction correction for the Gulton P420M-6 microphone are described. The diffraction correction was measured for two microphone mounting configurations at several angles of sound incidence over the frequency range 400 cps to 25K cps. In addition, the random incidence response for the Gulton P420M-6 microphone was obtained over the same frequency range. Analysis of the measured data shows that the precision of the measurements is very good below 15K cps (standard deviation being within plus or minus .6 db) and gradually decreases at higher frequencies (standard deviation being plus or minus 1.2 db at 20K cps and +3.9 db, -7.4 db at 25K cps). The pressure calibration for the Gulton P420M-6 microphone was obtained using the well known coupler method and also using an electrostatic actuator. The results of these measurements show that the electrostatic actuator method of calibration produces reliable results when used with the Gulton microphone.
Report Availability
Full text available
Date Issued
1967-05
Provenance
Lockheed Martin Missiles & Fire Control
Type
report
Format
1 online resource
Media
AFFDLTR66-223.pdf