Mixes stereo audio together to create mono output in both channels.

StereoToMono promo image
What is StereoToMono?

StereoToMono is a Firefox add-on that mixes stereo audio together, creating mono output in both channels. It allows you to listen to videos or audios in mono, balancing stereo images, resolving phase correlation issues, or using a single speaker.

Stats date:
By: no9
Users: 77
Rating: 4.00 (4)
Version: 1.2 (Last updated: 2023-08-02)
Creation date: 2022-08-29
Weekly download count: 11
Firefox on Android: Yes
Manifest version: 2
  • activeTab
  • contextMenus
  • storage
Size: 76.12K
Risk impact: High risk impact
Risk likelihood: Moderate risk likelihood

Other platforms

Not available on Chrome
Not available on Edge

This extension monofies the currently playing video or audio source with a single click on the extension button.

The StereoToMono extension is useful if you want to listen to the video or audio you are currently watching in mono. It combines the left speaker's content with the right speaker's and vice versa, so you effectively hear the same sound from both speakers. This can be helpful when the stereo image in the video is unbalanced, heavily leaning to the right or left, suffers from phase correlation issues, or you simply want to hear the entire audio using only one speaker.

It works on both video and audio elements on pages that support this feature. The extension is activated by clicking the left mouse button on its icon. For a full sound reset after adjusting the volume with the extension, it is recommended to reload the page.

You can set the sound in your browser permanently for the current browser session (until you quit Firefox) by using the preference setting located under the right-click menu. Please use this with caution, keeping in mind potential issues listed below.

Known issues:

  1. On some pages, it is not possible to adjust the stereo image of the played elements. This is due to how the specific page is designed.
  2. On some pages, when clicking on the extension button, the browser may mute the sound. This is due to the security configuration of the specific page or the server it is hosted on and unfortunately cannot be detected from the extension's point of view.
  3. This addon may interfere with other extensions that also alter the sound at the same time. Please keep this in mind.
If you find this extension useful, you may consider supporting the author with a donation of any amount. Check the menu by right-clicking the extension button.
User reviews
I hope this extension will not cause security problems. It works, it works perfectly the position to mono of a video from any page, be it Youtube, TikTok or anywhere else. It works very well. What I do hope is, that it has no security problems for navigation, I have reviewed the source code from top to bottom, I do not see any problem. This extension does not exist, nor does it have any external links, nor does it have remote links.
by sjlopezb, 2023-03-11
View all user reviews
Risk impact

StereoToMono is risky to use as it requires a number of sensitive permissions that can potentially harm your browser and steal your data. Exercise caution when installing this add-on. Review carefully before installing. We recommend that you only install StereoToMono if you trust the publisher.

Risk likelihood

StereoToMono is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.

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