This is the sound of the spring in my step now go forth and use it to lighten the load. . . . . . . Space cadets !!!!. (-:-). . . . . . . . . . . . . /\. . . . . . . . . . . \0/.
This is a flageolett sound played with plectrum on a steel-stringed acoustic guitar. I used this sound for coursera course "audio processing for music applications".