Tone Graph lists apps that are making sound and available audio outputs, then lets you pick a service and a destination device. Start routes that app’s audio to the chosen output (via WASAPI process loopback, with VB-Cable when needed so speakers stay clear). Stop restores the app’s previous default device when you close or stop cleanly. A live waveform shows the routed signal in real time. Refresh updates the service and output lists. The UI is a dark Win32 window with brand header, two lists, Start/Stop, and status text. When a source is selected, a small now-playing panel appears with cover, title, and artist from Windows SMTC; otherwise the graph keeps the full width.