This dataset consist of 12 hand selected musical stimuli to evaluate source count experiments. However, to better study the influence of vibrato we require extended control over certain parameters such as note duration, vibrato duration, exact fundamental frequency, vibrato rate, vibrato extend, reproducibility, loudness or expression. As mentioned in the previous chapter, vibrato techniques vary across instruments. Instruments such as violin and saxophone are known for their distinct frequency modulations. Other instruments such as the English horn and the flute are more close to amplitude modulations. We generated the notes using a software sampler which allows us to control the parameters such as the vibrato. All our test stimuli have a duration of three seconds. Items were equalized in loudness by using an iterative calculation of the loudness algorithm of the time-varying Zwicker model. We rendered 29 notes of C4, resulting in 841 unique unison instrument mixtures per pitch class.