3M SE Music Mixer User Manual


 
80 Additional options
Reverberation options
Models SE and DL
Reverberation options
The following setup options are selectable via the Reverberation Time
Options Setup menu (displayed in Figure 6-3).
Table 6-1: Reverberation time set-up options
Field Description
Explanation of field selections
Method -
Selecting the
calculation process
of RT60 reverb
time.
Interrupted (This is the default method setting.)
Interrupted method uses a constant sound source (i.e., dodecahedral
speaker), waiting for the level to stabilize, and then the source is turned
off. (The method uses random noise or pink noise to test reverb. time.)
Impulse Impulse method is when the user tests the room with a
broad spectrum impulsive noise, such as a starter pistol or a balloon
popping.
Averaging
Selecting how it will
calculate Average
for Reverb-time
Measurement – The RT60 result times for each filter band of the 1/1
Octave or 1/3 Octave modes are averaged across the studies to arrive at
a session average RT60 for that frequency band.
Ensemble - The decay curves for each filter band of the 1/1 Octave or
1/3 Octave modes are averaged across the studies to arrive at an
average session decay curve for that frequency band that is then used to
calculate the session RT60 for that band. This results in either eight or
twenty-four session ensembles, one for each frequency band in 1/1
Octave or 1/3 Octave modes, respectively.
Threshold -
Specifies the dB
level for triggering
the start or run of
the instrument. The
interpretation of this
field is dependent
on the
measurement
method.
Auto - (This is the default threshold setting.) The instrument will
automatically chose the level and calculate RT60. When in run mode, it
sets the threshold relative to the noise level in the room. It provides a
trigger level which is customized to each band.
40 dB 140 dB (in 1dB increments). The threshold decibel is user-
selectable between 40 dB to 140 dB in one decibel increments.
For Interrupted Noise method, level below this threshold will trigger
the start of a measurement.
For Impulse method, levels above this threshold will trigger the start
of a measurement.
Measure -
The expected
decay value
Auto - (This is the default Measure setting.) The instrument will
automatically pick the best Txx value based on the expected decay (i.e.,
T
20
).
T60 (T10 – T60) – (The default setting is Auto.) The selected “Txx
value is the actual amount of drop/decay the instrument measured. The
selectable ranges are T10-T60.
Filters -
1/1 or 1/3 bands
Measurements are plotted and stored in 1/1 or 1/3 octave band chart
and decay chart. This field is only selectable if both 1/1 and 1/3 octave
filter bands are installed features. Otherwise, the instrument will apply
the installed filter.