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Channel Groups and Multi-Unit Control

basic

Overview

Channel groups are one of the most powerful features of the WVC product line. They let you assign RCA output channels, across one or more WVC units, into logical groups that can be controlled independently or in a relative (chained) relationship. This article explains how channel groups work, how to configure them, common deployment architectures, and how to use multiple WVC units together in a single wireless mesh.

What Is a Channel Group?

A channel group is a collection of one or more RCA output channels that are controlled together by a single encoder or knob action. Each group can be given a custom name (for example, "Front", "Sub", "Rear") that appears on the knob display, the RTC screen, and in the app. You can have as many channel groups as you have channels, and each group can be set to one of two modes:

  • Standalone: Volume is fully independent of all other groups.
  • Relative: Volume moves proportionally to a parent group. Example: If Channel Group 2 (subwoofer) is set to Relative to Group 1 (mids/highs) at 50%, and you turn your mids/highs down to 50%, your subwoofer output will automatically be at 25%, maintaining the same relative balance.

Default Channel Group Configuration

By default, all output channels on a unit are assigned to a single channel group, so the knob controls all channels together. You can reconfigure this in the AuralSync app under Device settings > Channel Groups. You can also use Advanced > Channel Groups on the RTC, a PRO knob, WDD-LITE or BassWatch. On a Single, Dual, Concentric or Quad Knob, use Advanced > Setup Channel Groups. See Configuring Channel Groups on a Knob or Display.

Switching Between Channel Groups on the Knob

Single Encoder Knob

  • Single click the top of the knob. The default action is to toggle between Fast Mode and Slow Mode volume stepping. You can change the click action on the knob itself, under Knob Settings > Click Action. The other option is Mute (a short press sets your channel groups to 0). After a Mute, a turn raises only the group the knob is on. Double-click to reach the next group and turn it up.
  • Double-click the top to cycle to the next channel group.
Note

Mute reaches up to 12 channel groups. With base station firmware 4.12.1 or newer, groups 13 and up keep playing. If you need Mute to silence everything, use 12 groups or fewer.

Multi-Encoder Knobs (Dual, Concentric, Quad)

On knobs with more than one encoder, each encoder controls a channel group, giving you simultaneous, instant control of multiple groups with no button presses. The Dual Knob and Concentric Knob have two encoders; the Quad Knob has four.

By default the encoders are spread evenly across however many channel groups your system currently has, and this mapping updates automatically whenever you add or remove a group:

  • Two groups: the encoders split evenly. On a Quad knob, the left knob (both left rings) controls Group 1 and the right knob (both right rings) controls Group 2.
  • As many groups as encoders: each encoder gets its own group. On a Quad knob with four groups, each ring controls one group.
  • More groups than encoders: the extra groups are reached by double-clicking, the same way a single-encoder knob cycles through them.

Channel Group Mode (firmware 4.1.2 or newer)

The Dual, Concentric, and Quad knobs add a Channel Group setting that controls how the encoders map to your groups. To find it, long-press an encoder to open the menu, then open Knob Settings. It offers three modes:

  • Linear (default): a double-click shifts the encoders together to the next set of groups, keeping them evenly spread. On the Quad knob the two rings of each physical knob move as a pair. The mapping re-balances itself across the current number of groups, so it stays sensible after you add or remove one.
  • Dynamic: each encoder advances to the next group on its own when you double-click it, independent of the others. Use this when you want to point individual encoders at different groups on the fly.
  • Manual: you assign each encoder to a specific group yourself, and those assignments stay put. Double-clicking no longer changes the mapping.
Note

Linear and Dynamic always re-balance the encoders across the current number of groups, so a double-click is only a temporary nudge. Only Manual mode makes a per-encoder assignment stick.

The single-encoder knob does not show this setting: with one encoder there is nothing to distribute, so it always controls the active group and a double-click cycles to the next one.

Assigning Encoders in Manual Mode

When you set Channel Group to Manual, an Assign Encoders... item appears in Knob Settings:

  1. Long-press an encoder to open the menu and go to Knob Settings.
  2. Set Channel Group to Manual.
  3. Open Assign Encoders....
  4. For each row (Encoder 1, Encoder 2, and so on), rotate to choose the channel group that encoder should control. The group's custom name is shown if one is set, otherwise "Group 1", "Group 2", and so on.
  5. Select Back to save. Your assignments apply immediately and persist across sleep and power cycles.
Tip

Manual mode is ideal when two encoders should share one group (for example, both left rings on a Quad knob set to "Front" while the right rings handle "Sub" and "Rear"), or any time you want a fixed, predictable layout that does not shift when the group count changes.

Chaining Relative Groups

Firmware supports chaining relative channel groups. For example:

  • Group 1 (Highs): Standalone, master volume
  • Group 2 (Mids): Relative to Group 1
  • Group 3 (Subwoofer): Relative to Group 2 In this configuration, turning down Group 1 cascades the volume reduction through Groups 2 and 3 proportionally. Each group can still be independently adjusted within its relative range.

Understanding Active Channels

Before planning your deployment, it helps to understand what an "active channel" means in this context:

  • A mono signal occupies one active channel (a single RCA connection carrying one signal).
  • A stereo signal occupies two active channels: a left and a right RCA connection carrying different audio data. This distinction matters when deciding how to assign your inputs and outputs across one or more WVC units.

Deployment Architectures

There is no one-size-fits-all answer for how to wire a WVC into your system. The right topology depends on how many amplifiers you have, whether you're using a DSP, and how much independent control you need. The following scenarios illustrate common approaches.

Scenario 1: Two-Channel Unit Controlling Two Amplifiers (Mono Channels)

A 2-channel WVC has one left and one right output. If you want to control two separate amplifiers independently (for example, a subwoofer amplifier and a mids amplifier), you can route one mono signal to each:

  • Channel 1 (left): Subwoofer amplifier
  • Channel 2 (right): Mids/highs amplifier Assign each channel to its own channel group. You can then switch between groups on the knob (double-click) to adjust subwoofer and mids levels independently. This gives you complete independent control of your entire system from a single 2-channel unit.

Scenario 2: Two-Channel Unit with Multiple Amplifiers on the Same Signal (Y-Splitter)

If you have a stereo left/right signal and want to feed it to more than one amplifier, you can use a Y-splitter, passive RCA splitter box, or an active device such as the LF Audio Multi-Amplifier Synchronizer or DD Audio ZDL to split the output to multiple amplifiers. All amplifiers on the split will be attenuated together as a single channel group.

See the warning below about what not to do with Y-splitters: splitting outputs to multiple amplifiers is fine; combining inputs is not.

Scenario 3: Six-Channel Unit for Full System Control

A 6-channel WVC provides six independent inputs and six outputs. A typical full-system deployment:

  • Channels 1-2 -> Front left / front right -> Mids amplifier
  • Channels 3-4 -> Rear left / rear right -> Highs amplifier
  • Channels 5-6 -> Subwoofer left / subwoofer right -> Subwoofer amplifier Each stereo pair can be assigned to its own channel group for independent control, or grouped together as a master volume.

Scenario 4: WVC with a DSP: Master Volume + Independent Subwoofer Control

A common and flexible topology when using a DSP:

  1. Your source signal enters the WVC inputs.
  2. The WVC outputs feed the DSP. This channel group acts as master volume control.
  3. The DSP processes the signal and sends its outputs to your mids/highs amplifiers directly.
  4. The DSP also loops one output back into a second WVC input channel, which then feeds the subwoofer amplifier. This channel group provides independent subwoofer level control. This gives you a master volume knob for the whole system plus a separate subwoofer trim, all from one WVC unit.
Note

If you are running a full DSP-based system with proper stereo signals on all channels, running mono signals into the WVC is generally not recommended. The DSP loop-back topology above is better suited to those builds.

Using Multiple WVC Units Together

The WVC wireless encrypted mesh allows you to link multiple WVC base units together. A single knob can connect to and control multiple units simultaneously. Channel groups can span channels that reside on different physical units.

Example: You have two 6-channel units linked together, for 12 total channels. You might assign:

  • Channels 1 to 4 (Unit 1) to Channel Group 1, set to standalone (master volume).
  • Channels 5 to 12 (across both units) to Channel Group 2, set to relative to Group 1, so they always track at a fixed percentage of the master.

A single mesh supports up to 24 channel groups across linked units, giving you fine-grained independent control over a large number of output channels. The RTC works with up to 23 of them.

Tip

Competition Mode works across linked base stations too. See Linked Base Stations.

Which Groups Each Controller Can Set

Not every controller reaches every group. Each one can set a single group's volume like this:

The AuralSync app shows each group's level. It cannot change volume.

With base station firmware 4.12.1 or newer, changing one group leaves every other group's setting as it is. A few things still change many groups at once:

  • MASTER on the volume dial of a PRO knob, WDD-LITE or BassWatch sets every group to the same level, groups 9 and up included.
  • Mute on a PRO knob, WDD-LITE or BassWatch sets every group to 0, groups 9 and up included. On their volume dial, tap the number in the middle (firmware 4.12.3 or newer). Tap it again to bring the levels back.
  • Mute on the RTC sets groups 1 to 23 to 0. Group 24 keeps playing. Double-press its knob (firmware 4.12.4 or newer). Double-press again to bring the levels back.
  • Mute on a Single, Dual, Concentric or Quad Knob sets groups 1 to 12 to 0. Groups 13 and up keep playing.

Bringing the levels back works only while everything is still silent. If a level changed in the meantime, it mutes again instead.

Note

If you use more than 8 channel groups, update every base station to firmware 4.12.1 or newer. On older firmware, changing one group from a knob or display could turn groups 9 and up off.

Linking Units

You can start the link from any LF Audio knob or display:

Then get the base station you want to add ready:

  • A new base station (never paired to anything): power it on. It is ready to link. There is nothing else to do.
  • A base station you have used before: hold its reset button for about 3 seconds, until its front light flashes. This resets it to factory settings. It erases that base station's settings and any knobs or displays paired to it.

The knob, RTC or display finds the new base station and links it. On the RTC, a PRO knob, WDD-LITE or BassWatch, pick the new base station from the list when it appears. Once linked, all channels from every unit appear together in the Channel Groups configuration screen.

When Pair WVC ends, the RTC, PRO knob, WDD-LITE or BassWatch restarts. This reconnects it to your own base station. It also restarts if you leave Pair WVC after selecting Start.

If the new base station cannot be linked, the screen tells you why. This works on the RTC (firmware 4.12.4 or newer), a PRO knob, WDD-LITE and BassWatch:

  • Update Needed: the new base station needs a firmware update first.
  • Not Compatible: that device cannot join a WVC system. Pick a WVC base station.
  • Already Linked: you picked your own primary base station.
  • Reset Needed: the new base station answered but would not link. Hold its reset button for about 3 seconds, then try again.
  • Not Added: the new base station was not added. Check that your primary base station is on.

Each of these screens offers Retry and Cancel.

Caution: Do not press the reset button three times to link a base station. Three quick presses only let a knob or display pair with that base station. They cannot link it to your system.

The Add Unit button in the AuralSync app (Mesh Network tab) does not link a base station by itself. It shows short steps that point you to Advanced > Pair Additional WVC on your knob, and it closes when the new unit joins. The Add Unit button on the 6-channel WVC-PRO touchscreen gets that base station ready for a new knob or display. It does not link a base station.

Note

Linking additional units requires base station firmware 2.0.0 or newer.

Relative Channel Groups in Detail

When a channel group is set to Relative, its volume is always expressed as a percentage of its parent group's current level.

Example:

  • Group 1 (master) is at 100% -> Group 2 (relative at 50%) outputs at 50%
  • Group 1 drops to 50% -> Group 2 automatically outputs at 25% (50% of 50%)
  • Group 1 drops to 0% -> Group 2 is also at 0% This allows you to set a permanent balance between amplifier sections that is maintained automatically as you adjust master volume, without needing to touch the subwoofer or secondary group separately.

Warning: Never Use a Y-Splitter to Combine Input Signals

A common mistake is attempting to use a Y-splitter to merge two stereo signals into a single RCA input. For example, combining a front left/right pair and a rear left/right pair into one input in order to control more amplifiers with fewer channels.

Do not do this. Here is why:

Signal Cancellation

Stereo audio contains different data on the left and right channels: different frequencies, different timing, and often intentional phase differences. When you electrically combine two RCA signals using a Y-splitter, the voltages from both sources are summed on the same conductor. If the two signals are out of phase with each other (even partially), they partially or fully cancel:

  • Two signals that are 180 degrees out of phase produce zero output, a completely flat, silent signal.
  • Two signals that are partially offset produce incoherent noise, a garbled mix that does not resemble either original signal. Real music signals are not perfectly in phase, so combining them this way produces unpredictable, degraded audio, not a useful summed signal.

Output Device Conflict

Each RCA output is driven by an active circuit (typically an op-amp). When you connect two outputs together via a Y-splitter, the output stages of both devices are now directly connected and fighting each other's voltage rails. This is electrically harmful and can damage the output stages of your source device, DSP, or WVC unit.

The Right Solution

If you need more channels of independent volume control than your current unit provides, add another WVC unit and link it to your mesh wirelessly. Do not attempt to combine signals with a Y-splitter.

Splitting one output to multiple amplifiers (one output -> Y-splitter -> two amp inputs) is fine. Combining multiple outputs into one input is not.

Naming Channel Groups

You can give each channel group a custom name (up to 10 characters) such as "Front", "Sub", "Rear", or "Fill". Custom names appear everywhere groups are referenced:

  • On the knob display when switching between groups
  • On the RTC screen in the Channel Groups editor and volume display
  • In the AuralSync app when managing groups

Names are set in the Channel Groups configuration screen (on the RTC, a PRO knob, WDD-LITE, BassWatch, or in the app) and automatically sync to all connected devices: knobs, other RTC units, and the app. Groups without a custom name display as "Group 1", "Group 2", etc.

On the RTC, when a channel pair belongs to a renamed group the display also appends the underlying physical channel(s). For example, a group called "Mids" covering Channels 5 and 6 displays as "Mids (ch5/ch6)". This makes it clear which physical RCA outputs each renamed group covers, so a renamed group never becomes ambiguous when you are wiring or troubleshooting.

Naming Voltage and Temperature Probes (firmware 3.10.0+)

In addition to channel groups, you can give the voltage input and each temperature probe a custom name. This is especially useful on the WVC PRO-6 where three temperature probes can monitor different parts of the system (for example, "Sub Amp", "Mid Amp", "Battery").

  • Set custom names in the AuralSync app under the device's settings.
  • Custom names sync automatically across the entire system. They appear on the RTC temperature legend, in the RTC color picker, in the base settings live voltage display, and in the app.
  • The on-device touchscreen and the RTC update probe names live, without needing to reboot or leave the screen.
  • If a temperature probe is unplugged on the WVC PRO-6, its label and graph line both hide cleanly so the display only shows probes that are actually reporting data.

Configuring Channel Groups in the App

  1. Open the AuralSync app and connect to your unit.
  2. Navigate to Device settings > Channel Groups.
  3. Add or remove groups: tap Add Group at the bottom of the tab to create a new group, or use the Delete Group button inside an empty group's expanded card.
  4. Tap each group name to rename it (optional, up to 10 characters).
  5. Move channels between groups: expand a group card, find the channel row, tap the swap-arrows icon, and choose the destination group.
  6. Set each group's mode: Standalone or Relative to [Group X].
  7. If Relative, set the percentage.
  8. Tap Save to push the layout to the base station. Unused groups are removed automatically.

Configuring Channel Groups on a Knob or Display

The RTC, the WVC Dual PRO Knob and WVC Quad PRO Knob, WDD-LITE and BassWatch have a channel group editor. A PRO knob, WDD-LITE and BassWatch need firmware 4.12.3 or newer for it.

  1. Open the menu and go to Advanced > Channel Groups.
  2. Set Channel Groups to how many groups you want.
  3. Select Group 1 Name, Group 2 Name, and so on to rename a group (up to 10 characters).
  4. Set each Group 1, Group 2, and so on to Standalone, or relative to another group.
  5. Each base station has its own row with its model, for example Unit 1: WVC-PRO. Under it, pick the group for Channel 1, Channel 2, and so on.
  6. Leave the screen. Your changes go to the base station when you leave.

Stay connected to your base station when you leave. If the link is down, your changes are not sent.

When you leave, any group with no channels is removed. The groups after it are renumbered. A removed group's name is lost. A group that was relative to it becomes Standalone.

On a Single, Dual, Concentric or Quad Knob

These knobs have a simpler editor. It cannot rename groups. It shows while the knob is connected to a base station on firmware 2.0.0 or newer.

  1. Long-press the encoder to open the menu.
  2. Go to Advanced > Setup Channel Groups.
  3. Set Channel Groups to how many groups you want (up to 12).
  4. Set each group to Standalone or Relative to another group.
  5. Under each unit, pick the group for each channel.
  6. Select Back. Your changes go to the base station.

Any group with no channels is removed when you select Back.