Scope is described as 'The PC based Soundcard Oscilloscope receives its data from the Soundcard with 44.1kHz and 16 Bit resolution. The data source can be selected in the Windows mixer (Microphone, Line-In or Wave)'. There are four alternatives to Scope for Windows, Linux, Mac, SAVIHost and VSTHost. The best alternative is Signalizer, which is both free and Open Source. Other great apps like Scope are Visual Analyser (Free), xoscope (Free, Open Source) and Zelscope (Paid).
Signalizer is a all-in-one signal visualizing package with a bunch of unique focus-points; real-time audio visualization with optimized 3D GPU graphics, everything being scalable and zoomable gridlessly as well as being arbitrarily precise in both settings and display.