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Preview of SoundSphere

SoundSphere by dzl

SoundSphere boosts quiet tabs up to 800%, shapes sound with Voice/Bass modes and EQ, and shows which Firefox tabs are playing audio — all processed locally with no tracking.

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About this extension
SoundSphere – per-tab volume booster + EQ for Firefox

SoundSphere helps you make quiet tabs louder, shape the sound, and quickly see which tabs are actually making noise.

It sits in your toolbar and opens a simple popup with a volume slider, audio modes, an EQ, and a list of tabs that are currently playing audio. Everything runs locally in your browser — no trackers, no analytics, and no external script requests.

✨ What’s new in 1.2

✅ Improved compatibility on more sites (especially Bandcamp and SoundCloud) so boosting and EQ work more reliably.

🛡️ Better Spotify behavior: when protected playback prevents advanced processing, SoundSphere switches to a stable Basic Mode (mute + 0–100%) and shows a clear notice.

🎛️ Firefox UI polish: EQ sliders now display properly styled colors (no more “plain” sliders).

🔊 What it does

🚀 Boost tab audio up to 800% (when supported by the site/player)

🎚️ Choose between Default, Voice boost, and Bass boost

🎛️ Shape sound with a built-in EQ

🔴 Show how many tabs are audible via an optional badge

🧭 Jump to any playing tab directly from the popup

💾 Remember volume per tab or use one global volume level

🎚️ Volume and audio modes

📈 The slider ranges from 0% to 800%

🔇 0% – mute

🔉 100% – original volume

🔊 100–600% – strong boost, generally usable

⚠️ 600–800% – “use at your own risk” range that can clip or distort

🗣️ Voice boost helps make speech clearer in videos and streams.

🥁 Bass boost lifts the low end for music and games.

🗂️ Tab list and badge

🔢 The toolbar badge can show how many tabs are currently playing audio (optional).

🧾 The popup lists audible tabs with their favicon and title.

🖱️ Click a tab in the list to focus it instantly.

⚙️ Settings

You can open settings from:

⚙️ the gear icon in the popup, or

🧩 the add-on’s Preferences page in about:addons

Options include:

🔴 Show/hide the audible tab badge

🧠 Remember volume per tab or use global volume

🆕 Always start new tabs at 100%

🧪 Enable/disable Experimental Overdrive (if present in your build)

Settings are stored using Firefox storage so they persist across restarts.

🔒 Permissions and privacy

SoundSphere requests:

🧭 tabs / activeTab – to show which tabs are playing audio and let you jump to them from the popup

💾 storage – to save your settings and optional per-tab volume

🌐 Host access (<all_urls>) – so SoundSphere can apply volume/EQ controls on whatever sites you choose to use it on (it needs permission to run on the pages where you play audio)

SoundSphere:

🚫 Does not send any data to external servers

🚫 Does not include analytics or tracking

🚫 Does not load remote scripts or fonts

🧠 Processes audio locally in your browser using the Web Audio API

Host access is only used to run SoundSphere’s audio control code on pages where you play audio; no browsing history is collected or transmitted.

⚠️ Known limitations

✅ Works best on standard HTML5 audio/video players (YouTube, embedded players, many music sites).

🛡️ Some services use protected playback (DRM) or audio pipelines that don’t allow advanced browser-side processing. When that happens (for example, on Spotify in some browsers/sessions), SoundSphere will fall back to Basic Mode so playback stays stable.

🖥️ If you need guaranteed loudness/EQ across all system audio, an OS-level mixer/EQ is still the most reliable solution — SoundSphere is designed as a clean, per-tab, browser-side tool.
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Permissions and data

Required permissions:

  • Access browser tabs
  • Access your data for all websites
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Add-on Links
  • Homepage
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Version
1.2
Size
326.41 KB
Last updated
10 days ago (Dec 23, 2025)
Related Categories
  • Appearance
  • Photos, Music & Videos
  • Tabs
License
MIT License
Version History
  • See all versions
Tags
  • mp3
  • music
  • youtube
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