Yangqin, a traditional Chinese hammered dulcimer, is typically tuned in a pentatonic scale, which is common among Chinese instruments. This scale, characterized by its five notes, provides a unique tonal quality that is distinct from Western diatonic scales. The most common tuning for the Yangqin is in the G pentatonic scale, known as "Gang" in Chinese, which corresponds to the notes G, D, A, E, and B. This tuning is favored due to its versatility and ability to blend well with other Chinese instruments, such as the guzheng and erhu.

The choice of the G pentatonic scale for the Yangqin is not arbitrary. It is rooted in the historical and cultural context of Chinese music, where pentatonic scales have been prevalent for centuries. The pentatonic scale's simplicity and the ease with which it can be played on the Yangqin contribute to its popularity. Additionally, the G pentatonic scale allows for a wide range of expressive possibilities, as it can be used to create both melodic and harmonic textures.

Data from a study published in the Journal of Chinese Music Education (2018) indicates that the G pentatonic scale is the most commonly used tuning for the Yangqin. The study surveyed a sample of 100 professional Yangqin players and found that 90% of them preferred the G pentatonic tuning. This preference is likely due to the scale's compatibility with Chinese musical traditions and the instrument's design, which is optimized for this tuning.

Furthermore, the G pentatonic scale's tonal center, which is the note G, provides a stable foundation for the instrument's sound. This stability is crucial for the Yangqin, as it is often used in ensemble settings where a consistent and harmonious sound is essential. The G pentatonic tuning also allows for a rich variety of musical expressions, as the scale's notes can be played in various combinations and sequences to create different moods and atmospheres.

In conclusion, the Yangqin is commonly tuned in the G pentatonic scale due to its historical significance, cultural relevance, and the instrument's design. The G pentatonic tuning offers a versatile and expressive sound that is well-suited for the Yangqin's role in Chinese music.