Second, tonality. A pentatonic scale , which coincides with the major pentatonic scale of Western musical disciplines, is often heard in min'yō from the main islands of Japan, see minyō scale . In this pentatonic scale the subdominant and leading tone (scale degrees 4 and 7 of the Western major scale ) are omitted, resulting in a musical scale with no half steps between each note. (Do, Re, Mi, So, La in solfeggio , or scale degrees 1, 2, 3, 5, and 6) Okinawan min'yō, however, is characterized by scales that include the half-steps omitted in the aforementioned pentatonic scale, when analyzed in the Western discipline of music. In fact, the most common scale used in Okinawan min'yō includes scale degrees 1, 2, 3, 4, 5, 6, and 7.
In April 1989, X Japan's second album Blue Blood reached number 6 and has sold 712,000 copies.  Their third and best-selling album Jealousy was released in July 1991, topped the charts and sold over 1 million copies.  They released two more number one studio albums, Art of Life (1993) and Dahlia (1996), before disbanding in 1997. X Japan actually signed an American record deal with Atlantic Records in 1992, but an international release never happened.  In the 1990s, L'Arc-en-Ciel and Glay sold millions of records, while Malice Mizer , La'cryma Christi , and Siam Shade also found success.