Tonespace is a chord generator and visualizer, which is available as VST and AU plugin as well as a standalone app. Thus, this tool supports handling both input and output MIDI. It is an unusual application in many respects, so it is quite likely that you would like to consult its online manual.
Although the tool is installed as many others by dragging it to Apps, it is a good idea to read its “Before you start” notes. This way, you will learn that, if you want to use it as a VST or AU plugin, it is necessary to copy the tonespace.component to specific directories. Unfortunately, this must be done manually.
The app supports two ways to generate chords. For this purpose, there is a music keyboard. However, you may prefer to move your mouse over colored customizable grids. Fortunately, Tonespace gives you plenty of options for shaping chords. In this respect, it comes with more than 50 grids, 18 keys, 14 scales and multiple chord types. Likewise, you can use octave-based spaces as learning aids. What is more, it supports using chord-generating algorithms that automatically fit chords to scales and keys.
The tool lets you configure audio settings by picking one of the available output device, a sample rate and the desired audio buffer size. Moreover, it allows you to try your configuration.
All in all, Tonespace is an excellent solution for handling scales and chords. I am sure it will be highly appreciated by music students or musicians wanting to experiment with sounds. Fortunately, this product is completely free to use.