ChatterBlocker uses digital audio technology to mask the sound of speech and other distractions so you can stay focused.
ChatterBlocker does not use noise-cancellation. Instead, it masks unwanted conversations with a soothing blend of nature sounds, music and background chatter. The goal is to render speech less intelligible, because intelligible speech is often the most distracting sound in the workplace.
ChatterBlocker also offers mindfulness meditation tracks intended to increase concentration, reduce distractibility and minimize the stress response to office noise.
Note: Although Finder indicates that this is version 1.0, the developer states that this is version 1.1.4.