Post on 04-Jan-2016
transcript
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
REVERBERATION TIME
DEFINITION:THE TIME REQUIRED FOR SOUND TO DECAY 60 DECIBELS AFTER THE SOURCE HAS STOPPED.
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
FORMULA
FORMULA:REVERBERATION TIME =
0.05 X ROOM VOLUME TOTAL # OF SABINES
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
ROOM VOLUME
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
ROOM VOLUME
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
ROOM VOLUME
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
ROOM VOLUME
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SABINES
SABINES:THE NUMBER OF SABINES =
SURFACE AREA X THE ABSORPTION COEFFICIENT
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
OPTIMUM REVERBERATION TIME
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #1
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #1
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #1
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #2
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #2
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #3
DETERMINE THE REVERBERATION TIME, AT 500 HERTZ, OF A CYLINDRICAL ROOM WITH A DOMED CEILING.
GIVEN:
THE CYLINDER HEIGHT IS 25 FEET.
THE CYLINDER & THE DOME HAVE A DIAMETER OF 50 FEET.
THE FLOOR IS HEAVY CARPET, ON FOAM RUBBER (ABSORPTION COEFFICIENT =0.57).
WALLS ARE COARSE CONCRETE BLOCK (ABSORPTION COEFFICIENT = 0.31)
THE DOMED CEILING IS PLASTER ON LATH (ABSORPTION COEFFICIENT = 0.06).
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #3
FORMULA:
RT= 0.05 VOLUME/TOTAL SABINS
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #3
STEP #1: DETERMINE ROOM VOLUME
CYLINDER:
V = 3.1415(502) X 25 4 V = 3.1415 (2500) X 25’ 4V = 49,087.4 CUBIC FEET
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #3
STEP #1: DETERMINE ROOM VOLUME
DOME:
V = 3.1415 X H2 [R-9H/3)]V = 3.1415 (625) X [25-(25/3)]
V = 32,724.9 CUBIC FEET
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #3
STEP #1: DETERMINE ROOM VOLUME
TOTAL VOLUME = 49,087.4 + 32,724.9 = 81,812.3 CUBIC FEET
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #3
STEP #2: DETERMINE THE TOTAL NUMBER OF SABINS
WALLS:
AREA = 2 X (3.14159) R X H = 2 X (3.14159) 25’X25’ = 3927 SF
SABINS = AREA X ABSORPTION COEFFICIENT = 3927 X 0.31 = 1217.4 SABINS
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #3
STEP #2: DETERMINE THE TOTAL NUMBER OF SABINS
FLOOR:
AREA = (3.14159)R2 = (3.14159)252 = 1963.5 SF
SABINS = AREA X ABSORPTION COEFFICIENT
= 1963.5 X 0.57 = 1119.2 SABINS
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #3
STEP #2: DETERMINE THE TOTAL NUMBER OF SABINS
CEILING:
SURFACE AREA = 3.14159 (H2 + R2) = 3.14159 (252 +252) = 3927 SF
SABINS = AREA X ABSORPTION COEFFICIENT
= 3927 X 0.06 = 235.6 SABINS
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #3
STEP #2: DETERMINE THE TOTAL NUMBER OF SABINS
TOTAL # OF SABINS:
STOT = WALLS + FLOOR + CEILINGSTOT = 1217.4 + 1119.2 + 235.6 STOT = 2,572.2 SABINS
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #3
STEP #3: CALCULATE THE REVERBERATION TIME
RT = 0.05 X (VOLUME/TOTAL SABINS) = 0.05 X (81,812.3/2572.2)
= 1.59 SECONDS @ 500 HERTZ
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #4
WHAT WOULD THE REVERBERATION TIME BE IF THE CARPET IS REPLACED WITH A CONCRETE FLOOR?
GIVEN:THE CYLINDER HEIGHT IS 25 FEET.
THE CYLINDER & THE DOME HAVE A DIAMETER OF 50 FEET.
THE FLOOR IS CONCRETE (ABSORPTION COEFFICIENT = 0.02)
WALLS ARE COARSE CONCRETE BLOCK (ABSORPTION COEFFICIENT = 0.31)
THE DOMED CEILING IS PLASTER ON LATH (ABSORPTION COEFFICIENT = 0.06).
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #4
STEP 1: DETERMINE THE TOTAL NUMBER OF SABINS
FLOOR:
AREA = (3.14159)R2 = (3.14159)252
= 1963.5 SF
SABINS = AREA X ABSORPTION COEFFICIENT
= 1963.5 X 0.02 = 39.3 SABINS
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #4
STEP 2: DETERMINE THE TOTAL NUMBER OF SABINS
TOTAL # OF SABINS:
STOT = WALLS + FLOOR + CEILINGSTOT = 1217.4 + 39.3 + 235.6
STOT = 1492.3 SABINS
REVERBERATION TIME
DEFINITION
FORMULA
ROOM VOLUME CALCULATIONS
SABINE CALCULATIONS
OPTIMUM REVERBERATION TIME
SAMPLE PROBLEMS
SAMPLE PROBLEM #4
STEP 3: CALCULATE REVERBERATION TIME
RT = 0.05 X (VOLUME/TOTAL SABINS)
= 0.05 X (81,812.3/1492.3)
= 2.74 SECONDS @ 500 HERTZ