4.4) Send Effects
An Auxiliary Send, Aux Send or Send Effect is the name for an additional output an Object can use to send Audio at a uniquely controlled Volume to special Bus called an Auxiliary Bus. One of the most common applications for Auxiliary Busses is to provide a way for a lot of different Objects to have a special effect such as a Reverb or Echo applied, without impacting the CPU performance as much as Insert Effects. The signal being sent to an Auxiliary Bus triggers the effect which is then later returned and combined with the unaffected-dry signal.
In this Platformer Game, the Player Character moves through the level filled with pre-defined zones that represent types of ambient spaces. Whenever it enters one of these zones, the game can then send specialized Game Calls that Wwise can use to activate an Auxiliary Bus that’s been set up with a corresponding Reverb Effect. This is exactly the case every time the Player Character takes the lower part of the level, underneath the highway bridges. You’ll now configure Wwise with an effect so that it can react accordingly. First, lets find out where in the level the Player Character enters such a reverb zone.
Go to the Designer Layout and click on the robot Actor-Mixer.
Since your Player Character’s sounds are to be affected by pre-defined zones within the game, you need to activate Use game-defined auxiliary sends in its Actor-Mixer’s Property Editor. Only now, every time the Game Object or Actor emitting sounds of your character within one of the pre-defined zones in the game, the Actor-Mixer in Wwise sends the Audio Signals of all its child Objects to an Auxiliary Bus. With the default Send Volume being 0dBFS, the Send Volume is at the exact level of the child Objects. Turning it up or down will increase or decrease the amount of signal being sent to the Auxiliary Bus, which results in an increase or decrease of the effect. (Pic01 Game-defined Auxiliary Sends)
Now open the Profiler Layout and make sure you can view the Sends in the Advanced Profiler.
If the Sends Tab is not visible, click the gear wheel icon in the upper right corner and check Auxiliary Send Data.
In this view you can see whenever the Player Character moves through a game-defined reverb zone in real time. You’ll see the name or ID of the Auxiliary Bus that is registered with a zone and also the Send Volume. (Pic02 Profiling Sends)
Start the game and connect to the game via Profiler. Try to find out where these zones are.
You should see that whenever the Player Character is underneath the highway bridges, a Send Effect is being activated. The Advanced Profiler shows the name of the Game Object or Actor emitting the sounds, which is the Player Pawn, the Wwise Objects that are affected, which are of course all Objects inheriting from the robot Actor-Mixer, the name or ID of the Auxiliary Bus and the Send Volume. (Pic03 Detecting Zones) You now have to create an Auxiliary Bus that matches the name of the implemented Bus in the game engine.
Go to the Designer Layout and create a new Sub-Bus to the Sfx Bus. Name it Returns. (Pic04 Returns Bus)
Typically there are lots of different ambient spaces within a game, that all need very specific reverberation. A Technical Sound Designer has to therefore create many Auxiliary Busses. Staying organized, you can of course group all Auxiliary Busses with an Audio Bus that Audio Engineers typically call “Returns”, because on this Bus the wet signals of individual Send Effects are being returned from the Auxiliary Busses to the Audio Mixer.
Click the Create new Auxiliary Bus icon in the main menu bar and name it “Tunnel”. (Pic05 Tunnel Aux Bus)
Go back to the Profiler Layout and start the and connect to the game once more.
You should now see the Tunnel Auxiliary Bus recognized by the Wwise Audio Engine. (Pic06 Profiling the Tunnel Aux Bus) Great! The only thing that is left to do is to find a Reverb Effect that reflects the environment in the game.
Go back to the Designer Layout an choose an effect for an insert in the Effects Tab of the Auxiliary Bus.
You can try out any preset from the Wwise RoomVerb or Wwise Convolution Reverb effects. When profiling, if you play the game and want to listen exclusively to the reverb, then press the Solo Buttons on both the Returns Bus and the robot Actor-Mixer.
After making your adjustments for the reverb, generate the SoundBanks.