The Channel Strip

The Channel strip

The purpose of this post is to teach the signal flow through a channel strip in Reaper, describing in detail every component of the channel strip including, its usage and position in the signal flow.

Before starting: Expanding the mixer

it is important to note that in Reaper, when you open the application, it displays only a compact view of the mixer:

Every channel strip looks like this:

You can resize the mixer control panel and to display a full view of the channel strips:

The following is the complete view of a Channel Strip:

The view modes can also be customized using the options from the "View" menu.

The Signal flow

When you look at a channel strip, the general idea is that sound moves from the top to the bottom. But you have to keep in mind that it is not exactly that way. There are some places where the signal flow isn't quite top to bottom. 

The signal flow is the following:

At the very top of the channel strip we have the input section. This could be a hardware input or a virtual instrument.

After that we find the inserts. The inserts are a collection of places that we can add effects, like gates, compressors, EQs, etc. 

The next thing we'll find in our signal flow are the sends. Reaper actually provides 3 kinds of sends:

• Pre-FX (these will actually be acting before the inserts)
• Post-FX
• Post-Fader  

The sends will route the signal to a destination which will usually be a bus or a hardware output (for monitoring purposes, for example). The channel strip includes knobs to set how much signal is going to that output.

After the pan knob, we really have the most important part of the channel strip: The volume fader.

Next, we have the mute button, which just turns off the sound of that track. And then, our solo button, which isolates that track by itself, muting all the other tracks.

Also in the middle of this signal flow there are the volume and pan envelopes. The pan controls the output of the signal in the left or the right channel, and the volume controls the main output. 

Finally, the audio signal will go into the Master Channel where all the audio streams will be mixed down.

Conclusion

This is basically how the audio signal flows in the mixer channel strip. For most controls you can think of a top-to-bottom signal flow, but it is important to keep in mind the special cases, an how they are going to affect your mix.

In real life, the actual signal flow can be quite complex, i.e. taking into account all the possible options, mutes, envelopes, etc.. The following diagram will give an idea of the complexity involved:








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Sources used:

• http://forum.cockos.com/showthread.php?t=59784