All click types (alveolar ǃ, dental ǀ, lateral ǁ, palatal ǂ, retroflex ‼, and labial ʘ) have linguo-pulmonic variants, which occur as both stops and affricates, and are attested in four phonations: tenuis, voiced, aspirated, and murmured (breathy voiced).
However, no Khoisan language allows a cluster of any consonant, click or otherwise, with sonorants like l, r, y or w. Miller concludes that the remarkably large numbers of consonants in these languages is real, a consequence of the greater number of permutations of clicks, where there are two places of articulation that can be independently manipulated.
[b] Phonetically, a linguo-pulmonic consonant is a click in which the forward and rear articulations are released independently.
The forward articulation, made with the lips or the front of the tongue, releases with a lingual airstream as in any click.
The modally voiced and breathy-voiced clicks tend to be prenasalized in the various languages which use them, for reasons which are not clear.
The breathy-voiced consonants of some languages such as Juǀʼhoansi, including clicks, contain a voiceless interval and are sometimes written with mixed voicing.
Miller (2003) attributes this to a larger glottal opening than is found in for example Hindustani breathy-voiced consonants.
In Juǀ’hõa, for example, they are written voiceless ⟨ǃx ǁx ǀx ǂx⟩ and voiced ⟨gǃx gǁx gǀx gǂx⟩, and in the old orthography ⟨qg xg cg çg⟩ and ⟨dqg dxg dcg dçg⟩; in Naro, they are (voiceless) ⟨qg xg cg tcg⟩, and in Khoekhoe ⟨ǃkh ǁkh ǀkh ǂkh⟩.