Audio Matrix (Crosspoints)
Finally, the last portion of the faders, gizmos, and doodads in the Audio Matrix; the crosspoints.
Each channel of input needs to be routed, told where to go. Think of the old telephone systems with phone plugs at the switchboard. “Operator” you would hear as you picked up your phone. You would say to who you needed to connect to. “One moment please”. The operator would then physically connect your line to the other person’s line.
This is kind of like that. Crosspoints define which inputs should connect to which outputs.
In this stereo example, input one goes to output one and input two goes to output two. Or … Left goes to Left, Right goes to Right. I could swap the patch by changing the crosspoints.
In this example I have a mono input but a stereo output. With this crosspoint setup the sound effect will only go to the left output. To set it to also go out the right output, I’ll quite simply place another 0.
Or here I have a stereo channel audio file that I want to go to 8 different speakers, each one needing the exact same sound, so I’ve set crosspoints from both inputs to each output. However, because that means I’m sending the output to sources of audio … which would potentially be much louder that the output wants … I’ve set both crosspoints to be -6dB. When these channels sum, combine, come together, we’ll perceive it to be the desired volume.
Here’s the same 8 channel system with a mono file.
Next, here’s a 5.1 surround sound system output using a simple stereo input. So I’ve set left, right, rear left, and rear right to pull individually, but the center channel and sub channel both want a little bit of both, so I give them both channels –6db again here.
And finally, here’s a 5.1 surround sound system with a surround sound audio file. This is pretty straight forward so I’ve done what we call a 1-1 patch.
Routing crosspoints can be very powerful, but I also find that it’s one of the elements that quickly becomes a trap for younger designers. As you’re adding audio cues, check your inputs, outputs, and crosspoints again and again making sure that you’re achieving exactly what you want.
Assignment
Take this sound effect and try
– Playing the audio in one ear, then the other.
– Balancing the audio so it’s stronger in one ear than the other.
– Swapping the audio outputs.
– Putting both audio inputs into both outputs, making a mono system.
Were You Listening?
As you are adding audio cues what should you do?
Answer
Check your inputs, outputs, and crosspoints frequently.