COMPARATIVE EVALUATION OF PREDICTED AND MEASURED PERFORMANCE OF A 68M3 TRUNCATED REVERBERANT NOISE CHAMBER

摘要

THE PERFORMANCE OF A MEDIUM SIZE, TRUNCATED REVERBERATION CHAMBER IS EVALUATED IN DETAIL. CHAMBER PERFORMANCE PARAMETERS ARE PREDICTED, USING CLASSICAL ACOUSTIC THEORY, AND COMPARED WITH RESULTS FROM ACTUAL CHAMBER MEASUREMENTS. DISCREPANCIES ARE DISCUSSED IN RELATION TO SEVERAL AVAILABLE EMPIRICAL CORRECTIONS DEVELOPED BY OTHER RESEARCHERS. OF MORE PRACTICAL INTEREST IS THE CONFIRMATION OF A RECENT THEORY STATING THAT THE PRESENT RULE OF THUMB FOR THE RATIO OF SPECIMEN VOLUME TO TEST CHAMBER VOLUME, APPROXIMATELY TEN PERCENT, IS OVERLY CONSERVATIVE AND CAN BE INCREASED BY A FACTOR OF AT LEAST TWO AND POSSIBLY THREE.