Especially important is the first track, demonstrating three types of the iwa-bue (stone-whistle), dating from the Jomon and Yayoi periods. The instruments are so simple that they usually produce only a few pitches. The tone color is also limited. The type of music actually played on these period is unknown to us, due to the lack of information. The performance on this disc, therefore, have to rely on the shape, construction, and sound of the flutes, which would give us basic information regarding the Japanese ancient music practices. It is believed that such flutes were used by ancient Japanese people to communicate with their native gods.
The second track includes a performance of the dotaku (bronze bell). This is also an important document.