Referring this table, the noise level in the 1/3 octave band
is calculated as follows
Each sound, played from each loudspeaker, had the level adjusted to be 72 dB in the 250 Hz band or 64 dB in the 500 Hz band, depending on which octave band
was most prominent for that specific sound and location.
It should be noted that the resolution for the ASHRAE Handbook results is in octave bands
and not 1/3-octave bands
In this standard, the equivalent continuous downwind octave band
sound pressure level at a receiver, [L.
Table 3 shows the equivalent levels for each octave band
determined by the SLM in a flat frequency weighting and a fast time weighting.
Noise level (total, the third-octave band
spectra and octave band
spectra) was measured along each section of road under 120 singly passing cars and 80 multiple-axle heavy vehicles (according to the Statistical Pass-By method).
Using the tables in AHRI 885, one can estimate the room sound levels only if one has octave band
sound power data as an entering argument.
For instance, the type of octave band
sound sources that are dominant, and the type of analysis to characterize the existing environment and to understand the potential location of such sound sources.
In Figure 2, examination of average background noise by octave band
reveals that there is no striking difference in noise levels by octave band
except at the lower frequencies (250Hz to 16Hz) when noise levels in Hospital 2 diverged, increasing by about 20 dB.
filters can be either passive or active analog filters that operate on continuous-time signals or analog and digital filters that operate on discrete-time signals.
The output of the analysis system consists of one-third octave band
sound pressure levels as a function of time, obtained by processing the noise signals through an analysis system with the following characteristics:
It also takes the frustration out of calculating the pressure loss through each exhaust component at the same time providing acoustical predictions by octave band
, Silex said.