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Ecotect Tutorial : Linked Acoustic Rays


In previous tutorials, you have looked at some of the various acoustic analysis tools offered by Ecotect. This tutorial introduces you to another of these tools, Linked Acoustic Rays, which is useful for interactively examining the performance of specific acoustic reflectors within a space.


You will need about 15 minutes to complete this tutorial.

Training and Accreditation

Successfully completing this tutorial fulfills two of the practical skills required for completing Level 2 of the Acoustic Design training module.

Resources Required

To complete this tutorial, open the file, located in the Examples folder of your Ecotect installation.


  1. Select the panel to the underside of the bulkhead above the stage apron. Use the Rays and Particles control panel to check that this plane has been assigned as an acoustic reflector. Make sure that this is the only acoustic reflector in the model.
  2. To perform a linked acoustic rays analysis, you also need a source object. In this model, the speaker above the stage acts as a source. Otherwise, select an object, and assign it as a source via the Rays and Particles control panel.
  3. You are now ready to begin the analysis. Go to the Calculate»Linked Acoustic Rays... menu item. The following dialogue box appears. At this stage, accept the default values, and then click Ok to proceed.
  4. Ecotect now generated the linked acoustic rays in the model using the settings specified in the previous step. You will notice that linked acoustic rays are very similar to the ray distributions you have created in previous tutorials, except that the objects used to generate linked acoustic rays can be adjusted interactively, and provide instantaneous feedback on the acoustic impact of such changes.
  5. To demonstrate this, select the speaker object (the source) located above the stage. Using the x,y and z nudge tools, move the speaker around on the stage and see how the source location changes the distribution of acoustic rays. In particular, note that nudging the z and x values of the source object has the most significant impact.
  6. If you find things in the model a bit hard to see from a perspective view, use the View»Front menu item to bring up an orthogonal, longitudinal view of the model. Alternatively, use the F7 keyboard shortcut to do the same.
  7. Now trying adjusting the angle of the reflector. Select the acoustic reflector via its edge, as visible in the longitudinal view. Remember you can use the Space key to toggle the selection until you get what you need.
  8. Press F3 to enter node editing mode for the selected object. Draw a selection window around the nodes along the left edge of the reflector.
  9. Using the z nudge, move the selected edge up and down, and note how changing the angle of the reflector changes the distribution of rays within the auditorium. Thus, using linked acoustic rays, it is possible to interactively analyze acoustic rays within a model, so as to determine the optimum location and angles for source objects, acoustic reflectors and absorbers.
  10. To clear the linked acoustic rays from displaying in your model, click on the Display»Model menu item, or use the F9 keyboard shortcut.

Ecotect Tutorial : Displaying Acoustic Rays
Ecotect Tutorial : Optimum Reverberation Times


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