Chapter 19: Automation with Parameter Modulation

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19 Automation with Parameter Modulation[edit]

19.1 The Concept[edit]

Parameter modulation is best undertaken by more experienced mixers. This chapter serves as an introduction, but inevitably (because of the complexity of the topic) it is not really pitched at the relatively novice user.

Parameter modulation takes REAPER's routing, channel splitting, automation and sidechaining capabilities to new levels. You should probably not attempt this chapter unless you already have a sound grasp of these and other concepts. If necessary, turn back to the chapter More REAPER Routing Examples and work thru it again. Parameter modulation at its simplest means using the level of a track's volume or one or more FX parameter to control the behavior of one or more other FX parameters on the same track or on a different track or on a number of tracks. Don't worry if at this stage you find this difficult to comprehend. The concepts of what this is and how it works will become clearer after you have worked thru some examples.

One relatively simple example might relate to the application of a chorus plug-in to a guitar or bouzouki track. Suppose that we wish to vary the wet level of the chorus throughout the track. We could, of course, accomplish this with the use of automation envelopes. However, this might involve quite a lot of work and the envelopes might need frequent readjustments. Let's take this idea a step further. We can define a relationship between the instrument's volume and the wet chorus level, so that as the volume increases the mix becomes drier, and vice versa. The chorus will seem to tail away when the instrument is played more forcefully and become gently more present during the quieter passages. Instead of creating a series of envelopes for our chorus, we can use parameter modulation so that the chorus mix will respond automatically and in real time to changes in volume.

Incidentally, this particular example can create an interesting effect of space and distance on the instrument, but as with most of the other examples throughout this User Guide, that is not the main point of the exercise. Changes in an effect like chorus are relatively obvious to the human ear. The main point of this exercise is to show you how parameter modulation is set up and used. It's then up to you to use and apply it in ways that you'll find will bring new life and vigor to your own mixes.

19.2 The Interface[edit]

We'll shortly work thru some examples which will show both how parameter modulation works and how you can go about using it. First, we need to introduce a few basic terms and concepts.

When you select a parameter to be modulated, you will initially see the window shown here (right). In this example, parameter modulation is about to be applied to control a compressor's threshold on a vocal track. This initial window features five basic controls. These are:

Enable parameter modulation, baseline value. This needs to be ticked for the parameter modulation (PM) to be applied. Unticking this box sets the PM to bypass.

The horizontal baseline value fader. This determines the starting value of the parameter being controlled. We'll come to an example shortly. Initially, leave this at its default setting (fully left).

Audio control signal. Ticking this option will open a window which is used to define both which track (or tracks) contains the audio signal that is to be used to control the parameter being modulated, and how you want the modulation to be applied. Don't worry, we'll get to an example soon!

LFO. This option allows you to use a low frequency oscillator signal (such as sine, square, triangle, etc.) to generate a tone to control the parameter being modulated. This is more likely (but not exclusively) to be used when it is a synthesizer parameter that is being modulated.

Link from MIDI or FX parameter. This option allows you to link one FX parameter (on a track or media item) to another. An example might be to ensure that as a track or item is compressed more heavily, some presence is added to the EQ (to compensate for loss of dynamics). Another might be that as the wet/dry balance on a delay effect is adjusted to add more delay, the pan position of the delayed signal is automatically moved further out. The possibilities really are endless.

Linking from MIDI events will be covered separately, towards the end of this chapter.

19.3 Defining a Parameter for Modulation[edit]

Parameter modulation can be used with track FX and/or take/item FX.

Illustrated below is an example of the Parameter Modulation window with just the Enable parameter modulation and Audio control signal options enabled. The table below that explains the main settings, what they do and how they are used. We will then go on to work thru some examples to show you how parameter modulation can be used.

Item Description Enable parameter modulation, baseline value with Fader The checkbox enables/disables parameter modulation on this parameter. The fader sets a default value for the specified parameter that is to be modified. However, if an automation envelope exists for the same parameter then that envelope will determine the baseline and this setting will be ignored.
Audio control signal Enables/disables control of the parameter by the audio signal in the specified Track audio channel.
Track audio channel This specifies which audio channel(s) ' for example, 1/2 or 3/4 ' contain the audio signal that is used to control the specified parameter. The selection of channels available will depend on how many channels have been previously defined for the track. In more straightforward applications, you will want to choose channels 1 + 2. This will ensure that the parameter is controlled by the audio signal on its own track. However, as you will see soon, you can choose a source other than channels 1 + 2 if you want an FX parameter on one track controlled by the audio signal from a different track. The latter case would be an example of sidechain parameter modulation.
Attack and Release These two factors determine the speed with which changes in the level of the incoming signal will be applied to the parameter. They work in a similar way to Attack and Release on a compressor. A higher attack setting will cause the parameter to respond more slowly to changes in volume in the source audio channel. A low release speed will cause the modulation to be adjusted rapidly as the volume then falls. A higher speed will hold the modulation for a longer period before doing so. Generally speaking, the higher the attack and the release settings the more gradual will be the parameter modulation response. The lower these settings, the more sensitive and immediate will be the response.
Min Volume and Max Volume These determine the range within which the signal on the track audio channel will be used to modify the FX parameter. For example, in the illustration shown, the parameter in question (chorus wet mix) on the track in question (track 4, Bouzouki) will only be controlled by the audio signal on channels 1 and 2 when its volume falls within the range - 24 dB to - 0.53 dB. If or when the signal is quieter than -24 dB or louder than - 0.53 dB the parameter modulation is in effect set to bypass.
Strength and Direction These determine the nature and the intensity of the relationship between the incoming audio signal and the parameter being controlled. For example, set to 100% positive as the incoming audio signal increases or decreases, then the parameter being controlled will also increase or decrease to the same degree. At 50%, the relationship will still be positive, but more moderate. You can think of this as being conceptually similar to a ratio control on a compressor. At 0%, the effect will be completely neutral.
Audio Control Shaping Signal Graph This graphical control helps shape the behavior of the parameter that is being modified. For example, if the direction is set to positive, then pulling the small red handle (in the centre of the diagonal line) on the graph fully to the bottom right corner will result in more modest increases in the value of the parameter being modified. On the other hand, pulling the small red handle (in the centre of the diagonal line) on the graph fully to the top left corner will result in greater increases in the value of the parameter being modified. Don't worry, we'll work thru an example soon.

The best way for you to understand how parameter modulation works is to try it out in practise. This first example will use several of the PM window controls. We will first select a parameter to be modulated, then set its baseline fader level, and then select the required audio control signal. Finally, we will define the relationship between the audio control signal and the parameter being modulated.

19.4 Defining a Parameter for Modification[edit]

To select an FX parameter to be modified, follow either of these sequences:

  1. Displaying the track's Envelopes/Automation window and click on the + for any plug-in to display the list of its controls.
  2. Click on the Mod button for any parameter that you wish to have modified by an audio signal. You will then see a small check box next to the Mod text for that item in the Envelopes window (as shown right).
  3. Close the Envelopes/Automation window.


  1. Open the track or item plug-in's FX window.
  2. With the mouse, click on the control for the parameter that you wish to modulate.
  3. Click on the Param button in the plug-in window, then choose Parameter modulation from the menu that is then displayed (as shown below).

Notice (right) that the name of the last touched parameter ' the one to which parameter modulation will be applied ' is shown dimmed at the top of the Param button menu.

19.5 Parameter Modulation with Audio Control[edit]

In this first example, we will insert a plug-in such as chorus into a track's FX chain, then use that track's audio signal to control the way that plug-in behaves.


  1. Open the file All Through The Night and save it as All Through The Night MOD1.
  2. Adjust track faders to get a reasonable mix. This could be Volume at -0.5 db, center, Guitar Body at 0 db, 55% left, Guitar Neck at 0 dB, 63% right, and Bouzouki at -4 dB, 15% left.
  3. Solo the Bouzouki track. While working thru this example, this is the only track that will be needed.
  4. Insert the JS: Delay/delay_chorus plug-in into this track's FX chain, and set the various parameters as shown here.
  5. Click on the Output Wet (Chorus) (dB) rotary in this plug-in. Notice that currently this is set at 0.0.
  6. Click on the Param button, then choose Parameter Modulation/MIDI link from the menu. This will open a parameter modulation window for the output wet parameter. Enable the option Audio control signal and select as the Track audio channels 1 + 2. Play the track.
  7. The wet rotary on the plug-in was initially at 100%, as shown here. However, as you adjust the baseline fader (in the PM window) while the track is playing, the wet value in the Chorus window (shown to the immediate right of the 2 in 2 out button) is also adjusted. Leave it with a wet mix level of about 50%.
  8. Set the various items in the Parameter Modulation window as shown below and play the track. You should notice the wet mix element of the chorus being faded down for louder notes and passages and up for quieter notes and passages.
  9. Now experiment! You should find that:
  • Moving the Attack and Release faders left will result in the wet mix chorus fader movements becoming more jerky. Moving them right should make them smoother.
  • Moving the Strength fader (negative) to the right will cause the wet mix chorus fader to be faded down for louder notes and down up quieter ones. Selecting positive reverses this.
  • Moving the Min Volume fader left will lower the threshold at which the parameter modulation is applied. Moving it right will raise the threshold.
  1. When you have finished experimenting, adjust the settings to those shown here.
  2. This instrument becomes louder as the song progresses. Play it, with the Bouzouki unsoloed. By the end, there is less chorus being applied to the bouzouki.
  3. Now play the song again. Drag hold of the handle on the graph, and use your mouse to drag it to the lower right position. Notice that the movements of the wet mix fader now become more modest.
  4. Now drag hold of the handle on the graph, and use your mouse to drag it towards the top left corner of the graph (as shown below). Notice that the movements of the wet mix rotary now become sharper and the wet mix level reaches lower values.
  5. Restore the graph to its earlier position (shown at step 10) when you have finished. Save the file.

19.6 Using an LFO Shape with Parameter Modulation[edit]

Now let's have some fun and use a low frequency oscillator to further modify the way parameter modulation is applied. Try disabling the audio control and turning on the LFO option. Start with some fairly conservative settings as shown below. Selecting the Tempo Sync option should help make for a fairly safe outcome!

The Speed setting controls the signal repeat rate.

Strength determines how much of the LFO signal is applied.

You can also adjust the default Phase setting.

As in the previous examples, direction can be negative, centered or positive.

Notice also the Learn phase button: this can be used to assign control to a MIDI or OSC device.

Compare how the track now sounds with PM enabled and disabled. If you are familiar with working with low frequency oscillators, you might wish to be a little more adventurous. Otherwise, just save the file as All Through The Night MOD1 LFO.

19.7 Using Parameter Modulation for Dynamic Compression[edit]

In this next example, you will use parameter modulation to dynamically adjust the settings to compress a vocal track in such a way that the threshold will automatically be adjusted during the louder passages. This gives you a more precise control over the compressor's operation than would otherwise be possible.


  1. Open the file All Through The Night MOD1 and save it as All Through The Night MOD1A.
  2. Pan the Vocal track to the center and set its volume at about- 0.5 dB
  3. Insert an instance of ReaComp into the FX Chain for the Vox track.
  4. Set the Threshold to about '24 and the Ratio somewhere around 4:1. Set Knee size to around 15dB. Set the Wet gain to about +1.6dB.
  5. As you play the song, adjust the settings to suit. One possible set of suitable parameter values is shown on the right.
  6. As you play the track you might feel that the compression at times sounds about right but at other times is being applied too heavily. This is where we can use the track's own volume level to control its parameters. In this example, we will do this with the threshold only, but it could also be done with the ratio if you wished to.
  7. Click once on the Threshold fader.
  8. Click the Param button for this plug-in.
  9. From the menu, then choose Parameter modulation/MIDI link.
  10. Study the suggested settings shown below and adjust your settings accordingly as you play the song. Refer to the comments below.
  11. Notice in particular how the attack and release setting levels, the shape of the curve and the volume settings all help prevent the threshold from being adjusted too radically.
  12. Save and close the file when finished.


By setting the Min Volume in the PM window to the same level as the Threshold in the ReaC omp window we ensure that the PM is only applied when the vocal is at its loudest. The Strength setting of 33% effectively means that for every 3 decibels by which the volume exceeds the min volume, the threshold will be lifted by about 1 dB.

Note: When you are using Parameter Modulation you should be prepared to tweak the various parameters carefully. Sometimes even the slightest change to a parameter value can significantly change the result. If at first you do not seem to get any result, experiment especially with adjusting the baseline value setting.

19.8 Bypass Mode[edit]

Whenever you create a parameter modulation for a parameter, a small box is added next to its name in the Envelopes/Automation window. This can be used to enable any of your parameter modulations, or set them to bypass mode (in which case they are of course ignored). Otherwise you can do this from inside the Parameter Modulation window itself.

In the example shown here, PM settings exist for the Threshold (currently enabled).

Also, note that clicking on the word Mod for an item where parameter modulation already exists will cause that window to be opened (even if it is currently disabled) so that you can view and/or edit the settings.

19.9 Parameter Modulation Under Parameter Control[edit]

By linking parameters you can use dynamic changes in one FX parameter to directly control another. In this next example you will do just this, linking a track's EQ gain with its compressor threshold, so that whenever the compression threshold is raised a little more warmth is automatically added to the track.

  1. Open the file All Through the Night MOD1A and save it as All Through the Night MOD1B.
  2. In the vocal FX chain, add an instance of ReaEQ (after ReaComp). Select Band 2. Set the Frequency to about 180 Hz, the bandwidth to about 2.00 octave and the Gain to 0.0 dB.
  3. With the ReaEQ window open, click on the Band 2 Gain control, then the Param button, then Parameter modulation/MIDI link to open the Parameter Modulation window. Select the option Link from MIDI or FX parameter.
  4. Click on the large button below the Link from MIDI or FX parameter option and choose ReaComp then Thresh (as shown here).
  5. Before playing the song, adjust the baseline value fader so that the Gain on Band 2 in ReaEQ is restored to 0 dB.
  6. Set the Offset fader to 10% and the Scale to +100% (see notes below).
  7. Play the song and save the file.

In the examples at 19. 5 and 19. 6 parameter modulation was used to create quite a dramatic effect.

In the examples at 19. 7 and 19. 9 the effect is more subtle.

The two controls Offset and Scale can be used to control the extent to which the controlling parameter (in this example the compressor's threshold) modifies the controlled parameter (in this case the EQ band gain).

The Offset fader increase (to the right) or decreases (to the left) by a specified percentage the value of the parameter being modified

The Scale fader covers a range from -100% to +100%. At -100% the relationship between the controlling parameter (threshold) and the controlled parameter (EQ band 2 gain) will be 100% negative: the EQ gain will be lowered exactly as the threshold is raised. At +100% the relationship will be 100% positive and the opposite will occur.

If you just want to control the whole range of the target parameter then just set the Baseline [B] slider to the left (0%), Offset [O] to 0% and Scale [S] to 100%. To control just part of the target parameter's range, first of all, work out what that part is in % terms. For example, consider an EQ gain band with a range of -24 dB to +24 dB and you wish to control the value between -12dB and +12dB. The percentage range is accordingly from 25% to 75%. Make sure that you can see the target parameter on the FX's GUI and the Parameter Modulation window and set the Scale [S] value temporarily to 0%. Drag the Baseline [B] slider 25% to the right and you should see the target parameter change to -12dB. Now set the Scale to 50% (that is 75% - 25%). That's it. There is no need to adjust the Offset. In fact, you won't need the Offset often. It can be used to slide the range up or down. Please note that the actual change is determined by the Offset % multiplied by the Scale %. Let's look at [B] = 50%, [O] = 0% and [S] = 25%, this results in a range of 50% to 75%. If we now set [O] to -40% the range changes to 40% to 65% the change is [O] x [S], that is -40% X 25% = -10%).

19.10 Using Parameter Modulation with an Envelope[edit]

When you have an automation envelope enabled for a parameter being modulated, then the baseline value will be determined by that envelope rather than by the baseline value fader in the parameter modulation window. When this happens, the baseline value that is actually applied will itself vary (according to the envelope) throughout the song. This can produce some interesting results.

Here we have added an envelope to control the Band 2 EQ Gain setting of ReaEQ. By clicking the Modulate button in the envelope lane we are able to open the Parameter Modulation window and take the necessary steps to ensure that the EQ gain will respond automatically to changes in the strength of the audio signal on this track. In this example, when the envelope is lowered just after the current position of the play cursor, the baseline value of the parameter being modulated will also be lowered.

19.11 Parameter Modulation under Sidechain Audio Control[edit]

This next example introduces another application for Parameter Modulation. In this case, we will use the audio signal from one track (a vocal track) to shape the sound of an instrument submix (that is, a folder track containing several instruments). This will be done in such a way as to cause the instruments to appear to pull back slightly during the vocal passages.


  1. Open the file All Through The Night MOD1 and save it as All Through The Night MOD2.
  2. Remove or set to bypass the delay plug-in in the Bouzouki track's FX chain.
  3. Insert a new track after the vocal track. Name this track Instruments and make it into a folder. Insert the three instrument tracks into this folder, as shown on the right.
  4. Add an instance of ReaComp to the Bouzouki track. This is needed only because the volume of this instrument increases quite significantly as the song progresses. We wish to pull this back a little.
  5. Set a threshold of around '15dB and a ratio of around 4:1.
  6. Select the Instruments folder and display its routing window. Set the number of track channels to 4 and add a receive from channels 1/2 of the Vox track to channels 3/4 of the Instruments folder.
  7. Open the FX Window for the Instruments folder and add an instance of JS: SStillwell/exciter. This will be used to brighten up the instrument a little.
  8. Settings similar to those shown here will definitely brighten the instruments, perhaps more than you would like. For the sake of this exercise, however, these levels should be fine.
  9. We are now going to use parameter modulation to ensure that audio signal from the vocal track drives down the mix level of the exciter. This will have the effect of helping the vocal to just float over the instruments a little.
  10. Click on the Mix % control, then on the Param button and choose Parameter modulation/MIDI link from the menu.
  11. When the PM window is opened, enable parameter modulation and choose Audio control signal (sidechain). Move the baseline value fader about a third of the way to the right.
  12. Select Track audio channels 3/4 and make the direction Negative.
  13. Adjust the other parameters so that as the vocal floats above the instruments the Mix % of the Exciter is smoothly and gently faded down.
  14. One possible solution to this exercise is shown below. But don't just dive straight in and copy these settings. Try to get there by yourself!
  15. Save the file when you are finished.

19.12 Using MIDI Links for Parameter Modulation[edit]

You can also use MIDI data to control parameter modulation. For example:

  • From a ReaControlMIDI parameter, live or recorded as an automation envelope.
  • From data/events entered or recorded in a MIDI editor CC lane.

For example, you could use an automation envelope to record changes in ReaControlMIDI's volume parameter, then use that envelope to control another FX parameter, such as the ratio setting on a compressor. Another example might be to use a MIDI Editor CC lane to record changes in an instrument's pan position, then adjust the wet/dry mix of an effect such as delay, so as to vary the delay length according to the pan position.

We'll start by looking at these two examples, then you can freely explore any of the many possibilities that are available. For the sake of simplicity, both these examples use DSK Virtuoso. This synth is freeware and very easy to use. If you wish to replicate this example, you can use any synth that you choose.

Example 1: Controlling ReaComp from ReaControlMIDI

  1. Create a new project file, add a single track Insert in the track's FX chain first ReaControlMIDI, then a synth of your choice.
  2. In arrange view, insert a new MIDI item about 30 seconds long, open the MIDI editor and compose a simple tune. Don't worry about the musicality ' just enter enough notes to produce a simple sound.
  3. Make whatever changes you wish to the synth parameters, to produce a reasonable sound.
  4. Open ReaControlMIDI. Make sure the Control Change section is enabled.
  5. Click on the volume control (to make it the last touched item), then click on the Param button (top of dialog box) and choose Show track envelope.
  6. Either record or by manual editing (as you prefer) create an envelope similar to that shown below:
  7. At the end of the FX chain, add an instance of ReaComp.
  8. Play the track. Set ratio to about 4:1 and adjust the threshold to engage the compressor during the louder passages. Return the cursor to the start of the track.
  9. Click on the ratio control, then on the Param button. From the menu, choose Parameter modulation/MIDI link. The dialog shown here will be displayed.
  10. Select Link from MIDI or FX parameter. Click on the button and from the available options choose ReaControlMIDI then Volume.
  11. The two controls, Offset and Scale have the same purpose as in the examples earlier in this chapter. Carefully adjust the offset control to return the ratio setting on ReaComp to about 4:1.
  12. Play the track. Adjust the scale control so as to achieve a gentle movement of the ratio control as the music grows louder and quieter.
  13. Save the file as PMMIDI. Do not close it.

Example 2: Controlling ReaDelay direct from a MIDI CC lane

You could create this example as a separate project or, as we are going to do here, add it to the existing file PMMIDI.

  1. Open your MIDI item in the MIDI editor. Add a CC lane for Pan Position MSB and draw in the necessary events to pan out to the right then back to the center twice or more, as shown here.
  2. In the FX chain, insert ReaDelay just before ReaComp. Set length (time) and length (musical) both to 0.0. Set Feedback to about -50.0 dB.
  3. Click on the Length (time) control to touch it, then on the Param button, then MIDI link, then CC, then Pan Position MSB.
  4. The Parameter Modulation/Link dialog will be opened. Click on the large button, then select MIDI then CC then Pan position MSB.
  5. Adjust the Offset and Scale settings so as to get a smooth increase and decrease in the delay length as the pan moves out to the right and back (while the song is played).
  6. Save the file!

More about MIDI links

In our two examples, we have built our MIDI links using in one case ReaControlMIDI data, in the other case Midi Editor CC lane events. Let's look at some of the other possibilities.

You would have seen this menu when you were creating your links in the earlier examples:

You can link from any of the event types shown on the right.

For CC 14-bit or CC, use the sub menu to specify the event type (this could be any MIDI editor CC lane).

For note or aftertouch, you can select any note.

Other options are pitch, program change or channel pressure.

You can also specify that the parameter modulation is only to be applied to a specified bus or channel.

19.13 Further Applications[edit]

This chapter has introduced you to just a few basic examples to help you understand what REAPER's parameter modulation is and how it can be used. In doing so we have barely scratched the surface.

Here are some other points to keep in mind:

With parameter modulation, the signal from any track can be used to control parameters on any other. For example, the signal from an audio track can be used to control parameters on a synthesizer, and a synthesizer's output can be used to control signals on an audio track.

If you are familiar with working with synthesizers and low frequency oscillators, you may have developed an understanding of different types of waveforms such as sine, square and triangle. You can use these LFO shapes in your parameter modulation. The opportunities here can take you well beyond the introductory example used earlier in this section.

Other applications for parameter modulation are limited only by your needs, your creativity and your imagination. For example, with this technique you are able to use the audio sinal from one track (or group of tracks) to control specific parameters on a noise gate on another track (or tracks).

Tip: Your parameter modulation windows and their settings will automatically be saved with any FX chains and/or track templates that you create.

19.14 Managing FX Parameters in the Project Bay[edit]

In Chapter 12 you were introduced to the Project Bay, including the FX Bay which can be used to help you manage and organize your various track, item and master FX.

The Project Bay also includes a FX Parameters Bay whose purpose is to assist you in managing the various FX parameter features discussed in this chapter (and elsewhere). From this single interface you can manage track controls, envelopes, parameter modulation and control surface assignment for all parameters for all active track, item take and master track FX.

The FX Parameters tab is located next to the FX tab of the Project Bay, displayed by the View, Project Media/FX command, and shown below.

This bay supports the standard project bay features explained in Chapter 12, including (where appropriate) the various commands on the Action and Options button, and from right-click context menus. Here we will focus solely on those aspects that are specific to FX Parameter management.

Whenever any of these features is added to any FX parameter (e.g. from the individual FX window, or from the FX bay), it will automatically be added to the FX Parameters Bay display. In the above example, Band 2 gain on ReaEQ on track 1 uses parameter modulation: this is shown in the Mod column, which also indicates that they are under the control of audio control signals (ACS). The Details column tells us that another parameter on this plug-in, Band 4 gain, is linked to Band 2 gain. The Envelope column shows that two parameters from ReaDelay on track 5 have armed and active automation envelopes. Two parameters from ReaComp on track 2 have had their controls added to the track control panel (or TCP, as indicated by the dots in this column), and one parameter from a Guitar/chorus plug-in (Track 3) has both a track control and an armed envelope. No parameter is shown in the Learn column as being under control surface control.

The table below summarises how you the Parameter FX Bay can be used.

In order to do this ' You do this ... Manage or modify an existing parameter's settings Right-click on the plug-in name and make your choice from the menu. For track FX, these are Show in track controls, add a track envelope, parameter modulation and learn (to assign to a control surface. For item/take FX, the options are track envelope and learn.
Manage or modify a different parameter on the same FX Right-click on the plug-in name and from the menu (shown above) choose Other FX parameters... Choose an option (show in track controls, track envelope, parameter modulation or learn) from the sub-menu, then select the required parameter from the list.
Manage or modify a parameter on an FX used in the project but not yet modified Select the FX Bay (not the FX Parameter Bay!) then right-click on the FX. Choose FX parameters from the menu, then from the FX Parameters list choose an option (show in track controls, track envelope, parameter modulation or learn) from the sub-menu, then select the required parameter from the list.