My subject is Daoist ritual, not “Daoist music”. But if we’re going to describe the performance of Daoist ritual, we can’t help writing about how it sounds. So “Daoist music” shouldn’t be some niche topic to be ringfenced.
The problem arises when it is music scholars who discover groups. No-one calls the many thousands of Daoist groups in south China “Daoist music troupes,” because the people doing the research there regard them—correctly—as Daoist groups, not Daoist music troupes. The Li family are Daoist ritual specialists, not “Daoist musicians”!
And the same goes for “Buddhist music” and “religious music”…
So I firmly reject the concept of “Daoist music” as some disembodied topic; however, “music” (let’s say sound) is always a core aspect of ritual, so one might say that scholars of Daoist ritual who avoid addressing music (or more coyly, disclaim expertise in it) are fatally limiting their ability to engage with ritual. It’s like someone with a fine kitchen and loads of glossy cookbooks, who draws the line at handling food or cooking. I trust my discussions of ritual sound will serve as a gentle introduction, but I recommend (ethno)musicology to scholars of Daoism, not least for its broader perspectives on society, change, and engagement.
Most discussion of Daoist ritual is silent. But the texts of Daoist ritual are never read silently; they are performed aloud, and never in ordinary speech mode. So we have no choice but to address sound—it is not extraneous but intrinsic.  By belatedly moving on to sound in Part Three of my book I may seem to be relegating it to a subsidiary role; instead, only now are we addressing the heart of ritual performance. That’s why we need films, too.
Household Daoists in north China identify three types of organized ritual sound, “blowing, beating, and reciting” (chuidanian): melodic instrumental music, percussion, and vocal liturgy. These are in reverse order of importance, with vocal liturgy primary. Chapters 14 to 16 of my book Daoist priests of the Li family treat them in turn.
And just as we found with the texts, all three styles can be linked to temple practice. The major elite temples in both Buddhism and (at least Complete Perfection) Daoism recognize only vocal liturgy accompanied by ritual percussion; melodic instruments are excluded. But in practice many local ritual traditions, including some prestigious urban temples, have used melodic instrumental music since early times,  and the shengguan instrumental suites too are considered “holy pieces.” Ironically, music scholars in China have paid much more attention to shengguan than to vocal liturgy.
Again as with the ritual texts, oral aspects of transmission are important. We saw how the melodies of the Li family’s vocal liturgy were never notated until local scholars, and Li Qing, did so in the 1980s; even their texts, contained in ritual manuals, were rarely consulted. By contrast, the percussion patterns and the shengguan melodies have long been notated; but as with the vocal texts, this was merely as an aid to memory, and again some Daoists would learn both mainly orally.
Transcription and analysis are etic exercises, potentially useful tools to aid our discussions. But the risk is that these pieces are not meant as objects of individual aesthetic appreciation; moreover, transcription, like analysing texts, may distract from the aural experience of performance. So consulting my transcriptions and discussions should only be an aid to familiarizing ourselves with the actual sound.
One point of such study is to reveal the technical complexities of what Daoists have to do, apart from any doctrinal elements. If we wish to understand Daoist ritual, it is not enough just to write about the ancient origins of the texts on the page—we also need a grasp of how they are performed.
One might say that the texts studied by scholars of Daoist ritual hardly have any real existence outside their sound. We may read ritual manuals, analyse doctrine therein, and so on, but these texts exist to be performed; the main medium through which they are performed is sound, and the sounds by which they are communicated are largely “musical.”
Still, if we are to consult an unfamiliar ritual manual (something that few household Daoists may have any great interest in doing, by the way), the content and structure of their texts rarely yield clear clues as to how to perform them: whether sung slowly, recited, chanted fast, solo or tutti, and so on (see e.g. my posts on the Invitation, and Presenting Offerings). Whereas the sung hymns are headed with a red circle before the title and written in individual lines of one couplet, with each new section indicated with another red circle at the head of a new line, the chanted scriptures are written continuously, suggesting that they are to be recited.
The scholar of Daoism might ask: does it matter, as long as the text gets transmitted? Instead, the Daoist would point out: we don’t consult unfamiliar manuals, we learn from our elders how to perform rituals. On a practical level, when we consult a silent manual surely it is worth knowing that it takes less time to whip through a long prose passage of several pages than to sing a slow melismatic hymn of only five couplets.
For a cogent discussion of the wider issue from Michelle Bigenho, see here.
 For an overview, see Bell Yung, “The nature of Chinese ritual sound”, in Yung, Rawski and Watson eds., Harmony and counterpoint: ritual music in Chinese context, pp.13–31.
 See my In search of the folk Daoists of north China, p.22.