Ikehara also performed zagaku (Ming music) before the King and the court on at least one occasion, in 1658, prior to the introduction of Qing music into Ryûkyû. The Magistrate of Music (gaku bugyô) at that time is known to have been Ganeko peechin Ken'eki.
His kafu (official lineage record) indicates that by the 1660s, there were fears or concerns within the Ryukyuan court that the Ming Dynasty music they had been using at court, based on that transmitted to Ryûkyû in the 1390s, had perhaps fallen away from the true, proper, traditional forms - i.e. that because so much time had passed, the melodies, method of playing, vocal style, or other aspects may have gradually drifted away from the authentic and proper form. Thus, the court requested Chinese investiture envoy Zhang Xueli in 1663 to provide instruction in Qing dynasty music; Chen Yi, a member of Zhang's party, then spent roughly two months teaching the Crown Prince and two similarly elite members of the court how to play a number of pieces on the zheng.
The following year, in 1664, Ikehara was appointed to serve as music instructor (楽師匠) for those who were to participate in a mission to Kagoshima that year. The Magistrates of Music at that time were Tamayose peechin Shuan and Noha (Nuufa) peechin Seichi.
This musical instruction was then passed along within the scholar-aristocracy, and Den was among the first to receive such training. He also participated, in 1670, in what the lineage records describe as the first Ryukyuan performance of Qing music for a formal court occasion - a celebration of the accession of King Shô Tei.
- Liao Zhenpei 廖真珮, "Ryûkyû kyûtei ni okeru Chûgoku kei ongaku no ensô to denshô" 琉球宮廷における中国系音楽の演奏と伝承, in Uzagaku no fukugen ni mukete 御座楽の復元に向けて, Naha, Okinawa: Uzagaku fukugen ensô kenkyûkai 御座楽復元演奏研究会 (2007), 109-110, citing Naha shishi 那覇市史, vol 7, Naha City Office (1980), pp552-553.
- Liao, 122.