Quick Start Guide

Navigate to any website with audio or video. Start playing some audio before moving on to the next step. Try:

• YouTube: youtube.com - Play any video
• SoundCloud: soundcloud.com - Stream music or podcasts
• Bandcamp: Music streaming with artist pages (some tracks may not be processed due to cross-origin audio)

Click the TabDSP icon in your browser toolbar. TabDSP can run as a popup, a sidebar (side panel), or a standalone window -- all share the same interface.

What you'll see:

• Title bar: "Tab DSP" with media count and sample rate (initially shows "-- kHz")
• Enabled checkbox: Currently unchecked
• Module blocks: INPUT, EQ, MB, COMP, LIMIT, OUTPUT (EQ is selected by default)
• Canvas area: Black spectrum analyzer with orange grid
• Meters: Inactive until you enable processing

You can open TabDSP in a standalone window using the button next to the title bar, or use the sidebar for persistent side-by-side processing.

Check the "Enabled" checkbox at the top of the panel.

What happens:

• TabDSP injects audio processing code into the page (takes ~1 second)
• Media count updates (e.g., "1 media" if one audio/video element is found)
• Sample rate displays (e.g., "48 kHz")
• If audio is playing, you'll see:
  • Spectrum analyzer showing frequency content (blue waveform)
  • Global meters (IN/EQ/MB/COMP/LIM/OUT) responding to audio
  • LUFS loudness measurement updating

The fastest way to hear TabDSP in action is to load a factory preset.

1. Click "Presets" in the toolbar to open the preset popover
2. Select a preset from the dropdown -- it loads automatically:
   • "Gentle Warmth" - Subtle bass boost and high-end air (works on all tiers)
   • "Music Enhancement" - Good starting point for most music
   • "Podcast Voice" - Optimized for speech clarity
3. Listen! The preset applies immediately (no clicks or pops)

What changed:

• EQ curve appears on spectrum (white line showing frequency response)
• Module bypass states may change (e.g., Multiband might activate)
• Meters show gain reduction if compression is active
• Audio should sound different—more present, clearer, or warmer depending on preset

Module Blocks (Top Row)

Click different module blocks to switch the canvas view:

• INPUT: Shows input gain knob (non-selectable, no canvas)
• EQ (cyan): Spectrum analyzer with draggable EQ points
• MB (purple): Multiband compressor with crossover controls
• COMP (orange): Compressor waveforms (GR, input, output)
• LIMIT (red): Limiter with stereo meters and ceiling line
• OUTPUT: Shows master gain knob (non-selectable, no canvas)

Canvas Interactions

EQ Canvas:

• Double-click anywhere to add an EQ band
• Drag points up/down for gain, left/right for frequency
• Scroll wheel on a point to adjust Q (bandwidth)
• Click a point to open floating control panel

Compressor Canvas:

• Drag the orange threshold line up/down
• Waveforms show: blue (input), orange gradient (GR), green (output)
• Hover to see level readout at cursor position

Limiter Canvas:

• Drag the orange ceiling line to adjust limiting threshold
• Stereo meters on right: PRE (input) and POST (output)
• Red GR envelope shows gain reduction over time

Bypass Modules

Click the power icon on any module block to bypass it:

• Bypassed modules show a "BYPASSED" overlay on canvas
• Orange arc routes signal around bypassed modules
• Consecutive bypassed modules show a spanning arc

Keyboard Shortcuts

• Tab / Shift+Tab: Cycle through modules
• A: A/B comparison toggle
• E: Bypass EQ
• M: Bypass Multiband
• D: Bypass Compressor (Dynamics)
• L: Bypass Limiter
• 1-8: Select EQ band (when EQ is active)
• Ctrl+Z: Undo
• Ctrl+Y: Redo

All knobs and sliders also support Arrow keys, Page Up/Down, and Home/End. See the UI Guide for complete keyboard accessibility details.

TabDSP saves settings in two ways:

Global Settings (Default)

Your current settings apply to all websites. Changes are saved automatically.

Per-Site Settings

TabDSP automatically saves settings per website. The scope badge in the toolbar shows the current domain:

• Settings you adjust on one site are saved independently for that domain
• Click "Reset" to revert the current site's settings to defaults

Example use case: You might want aggressive bass boost on Spotify but neutral settings on YouTube.

Settings Popover

Click the gear icon in the toolbar to access advanced options:

• Auto-Enable: Automatically enable processing when you interact with a page or audio starts playing -- no need to manually check "Enabled" each time
• Cross-origin audio processing: Enable processing of audio from supported streaming sites (e.g., Bandcamp). May require page reload

Custom Presets

To save your current settings as a reusable preset:

1. Dial in your perfect settings
2. Click "Presets" in the toolbar, then click "Save"
3. Enter a name (e.g., "Evening Listening")
4. Preset appears in the dropdown for future use

Preset features:

• Export: Download preset as a .tabdsp file
• Import: Load a .tabdsp or .json file via file picker or drag-and-drop
• Delete: Remove custom presets (factory presets can't be deleted)

LUFS Stack

For loudness analysis and broadcast compliance, TabDSP includes the LUFS Stack -- a collapsible panel below the main canvas showing Momentary, Short-Term, and Integrated loudness bars, a target validator, and a loudness histogram. See the Limiter documentation for details on LUFS metering and compliance presets.

Common First-Time Questions

"I don't hear any difference"

• Check that "Enabled" is on
• Try loading "Loud & Punchy" preset for obvious difference
• Use A/B button to compare before/after
• Some presets are subtle—try "Music Enhancement" on well-produced tracks

"Processing stopped working after I switched tabs"

This is normal. TabDSP processes audio per-tab. When you return to the original tab, processing resumes. The extension always controls the active tab.

"Can I process multiple tabs at once?"

Yes, but each tab is processed independently with its own settings. Global settings apply to all tabs unless you set site overrides.

"Where did my custom preset go?"

Presets are saved in browser storage and persist across sessions. If you loaded the extension temporarily (developer mode), settings are lost when you close Firefox. Use the signed .xpi installation for persistence.

"Why does the spectrum analyzer look different than my DAW?"

TabDSP uses an FFT with constant-Q power summation (512 log-spaced bins, Q=12) instead of a raw linear FFT display. This gives constant relative bandwidth at all frequencies, matching how we hear pitch. Most DAWs display raw FFT bins. TabDSP's approach is similar to FabFilter Pro-Q 4 and Voxengo SPAN.

Next Steps

Now that you're up and running, dive deeper into specific modules: