Stimmhaft

Stimmhaft is a term used in phonetics and phonology to describe sounds that are produced with vibration of the vocal cords during articulation. Sounds that use vocal fold vibration are described as stimmhaft, while those without vibration are described as stimmlos (unvoiced).

The distinction applies to vowels and consonants. Vowels are typically stimmhaft by definition, whereas consonants can be either stimmhaft or stimmlos. Examples of stimmhafte consonants in many languages include the voiced stops [b], [d], [ɡ] and the voiced fricatives [v], [z]. The corresponding unvoiced partners are [p], [t], [k] and [f], [s], respectively. Notation in linguistic descriptions often uses the feature [+voice] to mark stimmhaft sounds or [-voice] for stimmlos sounds.

Physically, voicing results from periodic vibration of the vocal cords. Acoustically, this inserts a regular glottal pulse into the sound, which can be observed as a periodic waveform in a spectrogram. The presence or absence of voicing is a key cue in speech perception and helps differentiate many phonemes.

Voicing also interacts with phonological processes. A well-known example is final devoicing in German and several other languages, where a voiced obstruent at the end of a word becomes voiceless in pronunciation. This demonstrates how the feature stimmhaft relates to both articulation and the routinized sound patterns of languages.