Viewing results
To view the results of your simulation click the Results button from inside the editor once the simulation has been completed.
You can also access the Results directly by clicking the Result icon next to your succesfully run simulations.
The Results view enables you to view the acoustic parameters and time/frequency plots for the selected simulation.
It is possible to:
- View results for a single source and a single point receiver.
- View results for a single source and the average over multiple point receivers.
- View results for a single source and surface receivers.
- Switch between viewing the hybridized results, wave-based results, or geometrical acoustics results.
- Compare parameters and plots for all the simulations that have been run.
- Download your results for the different acoustic parameters as an excel sheet.
- Download IRs for a selected source as a zip file.
Result calculation methods
Each simulation in Treble returns results from both the wave-based solver and geometrical acoustics solver, unless otherwise has been selected.
When viewing results for full frequency bands beneath the selected transition frequency the results are calculated from the squared impulse response from our wave-based solver.
For frequency bands above the transition frequency the acoustics parameters are calculated from the energy histogram from our geometrical acoustics solver
If you have selected a transition frequency within an octave band the results of that band are generated from the hybrid impulse response from our wave-based solver.
Result views
There are three different views to select from in Results view:
- Report View (left button)
- Model View (middle button)
- Surface Receiver View (right button)
Adding Simulation for Comparison
When accessing the Result view, the simulation you have chosen to open will automatically be designated as the first comparison. You have the option to include up to six simulations for comparison.
When clicking "Add Simulation +", a popup will appear where you can select a simulation from all previously run simulations of your spaces and models.
When you select a simulation from the popup, that simulation will automatically become the selected comparison in the Result view. The selected comparison will be highlighted with a green border (see image above) and the simulation details will be shown in the sidepanel to the right.
Keep in mind that you cannot edit the simulation while in the Result view. You can toggle the "hide layer" and "hide surface receiver" functions by clicking the eye-icon next to each surface and next to each surface receiver.
You can remove any comparison by clicking the "trashcan" icon in the bottom right of the panel. You can also download results for each one by clicking the download icon in the bottom left. Additionally, You can also edit the simulation label (the simulation name), without changing the simulation name permanently.
Selecting point receivers
When viewing point receiver results you will have the option to either select a single receiver or multiple ones. If multiple receivers are selected, average results over the selected receivers will be displayed for each acoustic parameter.
To toggle between a single selection and multiselect you will need click the Receivers input which will open up a select list. If there were more then two point receivers in the selected simulation a toggle will be displayed at the top of the list. To switch between single or multiselect mode, click the toggle.
Acoustic parameters in Treble
EDT (Early Decay Time) is a reverberation time measure based on the slope of the 10 dB drop of the calculated energy decay curve. EDT is often more closely associated with the perceived reverberance of a space. See Reverberation Time. Note: if the energy decay curve is linear (a straight line), T20 = T30 = EDT
T20 is a linear estimate of the reverberation time based on the time it takes to decay 20 dB after the first 5 dB in the energy decay curve. i.e. T20 = triple the time it takes to decay from -5 dB to -25 dB. See Reverberation Time.
T30 is the similar to T20 except it uses a 30 dB decay instead of 20 dB to linearly estimate the reverberation time, i.e. T30 = double the time it takes to decay from -5 dB to -35 dB. See Reverberation Time.
C50 is a measure of speech clarity. C50 is the ratio of the early sound energy (between 0 and 50 ms) and the late sound energy (that arrives later than 50 ms). Measured in dB. See Clarity and definition.
C80 is a measure of music clarity. C80 is the ratio of the early sound energy (between 0 and 80 ms) to the late sound energy (that arrives later than 80 ms). Measured in dB. See Clarity and definition.
Note: a low C50/C80 value indicates poor speech intelligibility since details in the speech will become masked by the long reverberation time.
D50 or Definition is the ratio of the early-to-late arriving sound energy, where the early sound is defined as the energy within the first 50 milliseconds of the impulse response. This can be calculated from C50 and is measured in percentage. See Clarity and definition.
TS Centre time is a measure of centre of gravity of the IR. It is measured in ms. See Centre time.
G (sound strength). Sound strength is the ratio of the sound energy of the measured impulse response at a certain distance to the response measured in free (anechoic) field at a distance of 10 meters from the sound source. It other words, it measures how much a room amplifies the sound.
See Strength.
Example: a calmer sound environment calls for a low G value, while a lecture hall or a concert hall calls for a higher G value.
STI (Speech Transmission Index). STI is a numeric representation measure of communication channel characteristics whose value varies from 0 = bad to 1 = excellent.
Example: a good STI should be at least 0.6. Above 0.75 it is considered excellent.
OOP - Open plan office parameters
In addition to the standard acoustic parameters mentioned above, our application also calculates specific parameters for assessing the sound quality in open-plan offices. These parameters are derived following the ISO 3382-3 standard, which provides detailed guidelines for setting up measurements (or simulations) to ensure their validity.
Please note that these specialized parameters will be displayed in the results within Treble, provided that at least two receivers are selected using multiselect. However, it is your responsibility to properly configure the simulation. Adherence to the setup guidelines is crucial for the results to be considered valid and compliant with the ISO 3382-3 standard.
It's a good practise to analyze the Spatial decay plots in context with the OOP results as it can give a good insight into the results
For further information about the standard and the parameters calculated see the Open plan office section in our "Acoustic parameters" documentation.
Reference:
https://www.acousticbulletin.com/room-acoustic-descriptors-rt-c50-and-gain