I've been using online "white noise" generators for over a decade because I find they reliably help me get in the zone for an hour or two of work. I didn't like the context switching cost of needing to find the active browser tab, so I created a mac menu bar app that makes it almost frictionless to enable/disable brown noise.
How to try it: See releases zip on the GH repo. It's macOS 13+, notarized.
Technical details: - brown noise via leaky integration - a low-pass, speech blocker via pink noise through a 10-band EQ - all synthesized in real time via AVAudioEngine
There's also a pay-what-you-want page on Gumroad: https://rahulp6.gumroad.com/l/hush
Always open to feedback or comments if this helps you in any way. TY!