Cabs and Cab IRs

By default, adding an Amp block automatically adds a matching cab block to ensure you attain the complete sound of a physical amp and speaker cabinet. However, Helix Stadium also works great with real power amps and wooden cabinets, in which case you should avoid adding a redundant Cab block to your signal flow. Read this blog for more info.

Unlike in the world of physical amplifiers, Helix Stadium makes it easy to audition a multitude of classic and modern speaker cabs, with swappable mics and numerous parameters to tweak them further. You can also load Cab IRs (Impulse Responses) with or in place of Stadium’s Cabs. A Cab block consists of any two of the following:

• Guitar Cab

• Bass Cab

• IR (Impulse Response)

Selecting a Cab or Cab IR

By default, when you add an Amp block to a preset, a Cab block is automatically added to its right, and the “matched” Cab appears in the left tab of the Cab block. To disable this behavior, from the Model List > Amp’s sidebar, tap the Add Cab Block toggle off. See the Amp & Preamp Models page.

You can also add a Cab block manually:

1. From the Home screen, tap an empty location on a path. Block categories appear in the inspector.

2. Tap the Cab button to open the Model List. Tap the list view button to choose to view more items in a condensed list (below left) or fewer items as large images in a grid (below right).

3. Swipe the list up or down (or turn the Lower Knob) to find the desired item.

   • Tap NO CAB, GUITAR CAB, BASS CAB, or CAB IR in the sidebar to quickly scroll the list up or down to that subcategory.

4. Tap to select the item and press Home (or tap the Inspector header) to close the Model List. Alternatively, double-tap to select the item and close the Model List.

5. To add a second Cab or Cab IR to the block, tap the right half of the Inspector Header and repeat steps 3 and 4 above.

Cabs

Each Cab in Helix Stadium is comprised of thousands of IRs. Cab blocks are unique in that they can contain one or two Cabs or Cab IRs (or one of each).

• When one Cab or Cab IR is loaded, the Cab block sums its incoming signal to mono.

• When two Cabs or two Cab IRs (or one of each) are selected in a single Cab block, the Cab block is stereo in and stereo out.

• Also see the Signal Path Routing page for tips on mono/stereo routing.

Hybrid Cabs from Helix/HX

Helix Stadium does not include the older Hybrid Cab models from Helix/HX (pre-3.50 firmware). When importing a Helix/HX preset into Helix Stadium, any Hybrid Cab blocks are automatically converted to a new Cab. They may sound better right from the get go, but note that they will likely sound different.

Cab > Focus View

When a Cab block is selected on the Home > Edit screen, tap the Focus icon in the Inspector to open Focus view. Tap and drag the Mic to set its Position and Distance relative to the Cab speaker, just as you would in the studio. Tap the 0°/45° toggle to set the Angle. These parameters, along with all other Cab parameters, can also be adjusted within the Inspector at the bottom of the screen.

When a Cab IR is selected, Focus view shows a static frequency plot if the IR file for reference, along with User Default, Factory Default, and Add to Favorites sidebar options, as described below. Please see the Cab IRs section below for more about using IRs.

Focus: While Focus view is shown, the icon appears white . Tap to exit Focus view.

Cab or Cab IR: Since a Cab block offers two tabbed slots, tap the desired slot to view its parameters. Loading a Cab IR is slightly different than loading a Cab—please see the following section on Cab IRs.

Mic: Tap and drag the mic to adjust the Position and Distance parameters.

Angle: Tap to set the preferred mic angle—0° or 45°

Sidebar: Several additional options are available here for the selected Cab model/Cab IR.

• User Default: If you find yourself constantly re-tweaking your commonly-used Cabs the same way, Tap User Default to save the Cab’s settings as its new defaults, so it always shows up the way you want. See Creating User Defaults.

• Factory Default: If you’ve stored User Default settings for the selected Cab model or Cab IR, tap Factory Default to return it to its original default settings for all future uses.

• Add to Favorites: Once a Cab block is configured to your liking, add it as a Favorite to easily recall it for future presets. See Adding a Favorite.

• Amp>Cab Link: By default, changing an Amp model will automatically recall a “matched” cab for the left tab of its linked Cab block. When an Amp and Cab block are linked, selecting one of them will display a gold link icon (see below). When off, changing Amp models does not affect the Cab block.

• Amp>Cab Link is only active when you add the Amp & Cab with the Amp Model List’s Add Cab Block toggle.

  • The Cab block’s right tab Cab model remains unchanged when Amp>Cab Link is enabled unless you also have Cab>Cab Link enabled (see the next item).

• Cab>Cab Link: Tap on to link both sides of a Cab block. When on, changing the left cab automatically loads the same cab on the right. This can be helpful when you want the same cab but different mics, or the same cab and mic but different mic positions or distances.*

  • Changing the right Cab does not affect the left Cab.

Cab Parameters

Cab IRs

Instead of Cabs, you can load one or two Cab IRs to a Cab block. Impulse Responses, or “IRs” are mathematical functions representing the sonic measurements of audio systems (in this case, speaker cabinet and mic combinations)—resulting in very short audio files that can then be loaded into an IR loader to provide a virtual recreation of the entire system—cabinet, speaker, mic, and perhaps even some post-processing like EQ. This process of “capturing” speaker cabs as IRs has made it possible to have an endless number of combinations of speakers, cabinets, microphones, mic placement, etc., for use with Helix Stadium and other amps and devices. Helix Stadium can load thousands of Cab IRs in nested folders, organized however you like.

Importing IRs

Importing IR files is easily accomplished using the free Helix Stadium application for macOS and Windows^® computers. Please see the Helix Stadium Application - Importing IR Files section.

Helix Stadium supports IRs in WAV (.wav) format. Regardless of the source WAV file’s length, sample rate, bit depth, and mono/stereo format, Cab IRs are processed internally as 2048-sample, 48kHz, 32-bit float, mono files.

Loading an IR within a Cab Block

Once you’ve imported IRs into Helix Stadium, you can select, audition, and load an IR within the Model List.

1. With a Cab block selected, tap the left or right side of the Inspector header to open the Model List (also see the next section).

2. Tap Cab IR in the sidebar to scroll to the bottom of the list, then tap on 2048 IR (below left).

3. Tap on the pink <EMPTY> box to open the USER CAB IRs file browser. Navigate the browser to find the IR you want and tap to audition it (below right). Double-tap an IR in the list to load it and close the Model List.

   • To clear the IR file from the Cab, tap the small X icon in the pink box .

The USER CAB IR Browser

Search Field: Tap to type a search term in this field to filter the list of IRs.

User Cab IRs Folder: Tap on this folder in the left column to display the list of all your imported User Cab IR files within the middle column.

Cab IR list: Once IR files have been imported into Helix Stadium, the middle column shows your library of User Cab IRs.

Sidebar: Allows you to manage your IR files.

Manage Files: Tap to show a list of options within the sidebar to manage the IR files. Check the box to select one or more IRs to apply the sidebar Copy or Move to Folder commands.

• Select All: “Checks” all IRs in the list.

• Deselect All: “Unchecks” all checked IRs in the list.

• Copy Files: Copies all checked IR files to the clipboard, letting you copy one or more User IRs and then paste them into a different folder or subfolder.

• Paste Files: Pastes the clipboard contents into the currently selected folder or subfolder.

• Move to Folder: Allows you to select one or more IRs and move them from their current list location into a selected subfolder.

• Delete Files: Permanently clears the selected User IR(s) from Helix Stadium.^*

Rename File/Rename Folder: Tap to rename the current IR file or subfolder with your own custom name.

New Folder: Tap to create and name a new empty subfolder. Use the Manage Files functions to copy or move IRs into the subfolders you create.

Inspector: Displays two Cab tabs and parameters for the selected tab.

• Cab/IR Tabs: A Cab block always lets you load two Cabs or two Cab IRs (or one of each). In the image above, the left tab has the Cab IR “LRS GOLD 1PC4” loaded, and the right tab is empty (No Cab).

• Focus Icon: Tap to open Focus view. Tap and drag the Mic to set its Position and Distance relative to the Cab speaker, just as you would in the studio. Tap the 0°/45° toggle to set the Angle. See Focus View.

Cab IR Parameters