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Preview of FreqKiller

FreqKiller by Comáro

Surgical notch EQ filter for browser audio. Kill bad frequencies from poorly mastered YouTube content.

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Extension Metadata

About this extension
FreqKiller applies surgical notch EQ filters directly to browser audio using the Web Audio API. Designed for YouTube and other streaming sites where content creators skip post-production EQ, leaving harsh or resonant frequencies in their output.

Features:
- Notch filter with configurable frequency (20–20,000 Hz), Q factor, and gain
- Multiple filters per session — stack as many notches as needed
- Real-time EQ curve visualization
- Per-filter enable/disable toggle and master bypass
- Settings persist across sessions
- Zero data collection — all processing is local, in-tab

Default preset: 5,500 Hz notch at Q 9.6 — tuned for the common upper-mid harshness found in poorly mastered video audio.
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Permissions and data

Required permissions:

  • Access browser tabs
  • Access your data for all websites

Data collection:

  • The developer says this extension doesn't require data collection.
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More information
Version
1.0.0
Size
18.17 KB
Last updated
4 days ago (Mar 11, 2026)
Related Categories
  • Privacy & Security
  • Photos, Music & Videos
License
MIT License
Version History
  • See all versions
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