This is a straightforward yet powerful app that acts as a polyphonic audio synthesizer with a virtually unlimited collection of sounds. Under the hood, It uses an AVAudioUnitSampler to generate the audio output when you touch one or more keys. The sounds that are available come from soundfont (SF2) files, such as those available online for free (and of variable quality).  The app also exists as an AUv3 plug-in (included) so you can use it in your favorite music generation application such as…