Tab DJ is a free Chrome add-on developed by David Schlachter. It provides per-tab stereo audio panning (balance) and volume control, making it a useful tool for audio enthusiasts and DJs. With Tab DJ, users can send one audio channel to their speakers while previewing another channel on a different tab.

This add-on works as a simple DJ app, allowing users to easily control the left-right balance and volume of audio on individual tabs. It can be used with a LR -> LL & LR DJ cable for enhanced audio mixing capabilities.

Tab DJ is free and open-source, with the source code available on GitHub. It requires permissions to access the content of a tab and capture audio from tabs in order to apply filters.

Overall, Tab DJ is a handy Chrome add-on for anyone looking for per-tab stereo audio control and DJ-like features.