105
SVANTEK 977W User Manual
13. REVERBERATION TIME MEASUREMENT - RT60
The
RT60
analysis is an optional function of the SVAN 977W instrument, which provides reverberation time
calculation for 1/1 octave bands (from 63Hz to 16kHz) or 1/3 octave bands (from 50 Hz to 20 kHz) and three total
RMS levels (
A
,
C
and
Z
weighted). Whole measurement process and calculations implemented in the SVAN
977W instrument fulfil the ISO 3382 standard.
The reverberation time of the room can be obtained with the use of the SVAN 977W instrument by two
measurement methods: Impulse Response Method
(
Impulse
) and Interrupted Noise Method
(
Decay
). The
selection of the method depends on the type of the sound source used by the user. The
Impulse
method is
designed for measurement using the impulse sound source (like pistol shot, petard explosion), whereas the
Decay
method is intended for measurements when room is excited by broad or narrow band sound noise source
(usually pink noise). For more details about the measurement and calculation process see Appendix H.
The reverberation time analysis applied in the instrument consists of two parts:
1. The measurement part during which the acoustic response of the room is registered.
2. The calculation part during which the reverberation time (
EDT
,
RT20
,
RT30
and
RTUser
) is calculated
for the measured room response.
Note: It
is
recommended
to
familiarize
with
the
Appendix H
before
proceeding.
This chapter describes only the navigation of the instruments, whereas Appendix H depicts
the definitions and description of the reverberation time measurement.
13.1. Selection of RT 60 function
To select the
RT60
analysis function the
user should enter the
Function
list by
pressing the
<Menu>
push-button, then
select the
Function
text and press
<ENTER>
. In the
Measurement Function
window the user should highlight the
RT60
line and press
<ENTER>
.
<ENT>
Note: It is not possible to change the current function during running measurements.
In this case the instrument displays for about 2
seconds the text: “Measurement in Progress”. To
change the current measurement function, the measurement must be stopped!
13.2. Setting the RT60 analysis
Execution of
RT60
analysis depends on a certain number of the parameters,
which can be set in the different windows of the
Measurement
list:
RT60 Settings
,
Compensation
Filter
and
Range
.
Positions
Compensation
Filter
and
Range
are the same as for other
instrument’s functions (see. Sections 5.6 and 5.7 of this manual).
