Here's a paragraph from a Miyagi Michio essay, Junsui no koe 純粋の声 ("Voices of purity"):

或る日音楽学校で、私の作曲したものを箏曲科の学生に歌わせたことがあった。何れも女学校を卒業した者か、またはそれ位の年頃の者であったが、その声の良し悪しは別として、それが非常に純粋な響きで私の胸を打つものがあった。唄が朗詠風のものであったので、私は歌わせていながら、何だか自分が天国に行って、天女のコーラスを聴いているような、何ともいいがたい感じがした。私は或るレコードで、バッハのカンタータを聴いたことがあるが、そのカンタータのコーラスが、わざわざ少女を集めてコーリングしたので、曲もそうであるが、普通のコーラスとは別の感じがして、私はその演奏に打たれたことがあった。私はその時、これから少女たちの声を入れたものを作曲してみたいと思った。

One day at music school I had students from the koto department sing one of my compositions. All were graduates from girls' schools or around that age [mid/late teens], and, as a separate matter from the merits or deficiencies of each voice, I was struck by the extreme purity of the overall sound. The song was in a traditional recitative style [朗詠風], the impression I received as they sang was quite indescribable, as if I had gone to heaven and was listening to a choir of celestial maidens [天女]. I once heard a record of a Bach cantata the kōringu of which had been performed by a choir made up exclusively of young girls. I was struck not only by the work itself but also the fact that the feeling was entirely different from a normal choir. That was when I decided I wanted to try composing works that included parts for girls' voices.

This was written in 1935; a dedicated music historian could probably make an educated guess as to which exact recording Miyagi heard.

Anyway, what interested me about this passage was the use of the word kōringu, which is obviously not from any premodern strata of Japanese. The most obvious interpretation is that it is a straight loan of "calling" from English, but it seems to be used here to mean either "performance" or "recording" and neither of these meanings quite fit "calling". I wondered if it might be some scribal error for rekōdingu, but Google Books shows it uncorrected in multiple collections containing this essay, as well as a 1935 Kawabata Yasunari essay also called Junsui no koe, published in Fujin Kōron magazine and later collected in Nihon no bi no kokoro 日本の美のこころ ("The heart/soul of Japanese aesthetics"). Kawabata's essay uses Miyagi's as a launching pad for some of his own thoughts on girls, purity, and Miyagi, and quotes the passage above without comment — so if kōringu is an error, it isn't a glaringly obvious one. Still, I can't find any other examples of the word being used in this way, which is suspicious.

Naturally, more exotic theories explaining the word do come to mind. For example: the Japanese for "[European art music-style] choir" is kōrasu , from English chorus, so maybe this is the -ing form of a backformed pseudo-English verb to chor, def. "sing as a choir", or the result of a mistaken assumption that call was that word, based on the similarity when kanafied. Before I wander too far into the wilds, though, does anyone have any wisdom to impart?