The so-called voiceless palatal-velar fricative (also called a voiceless dorso-palatal velar fricative, voiceless postalveolar and velar fricative, or voiceless coarticulated velar and palatoalveolar fricative) covers a range of similar sounds used in most dialects of Swedish and transcribed as . In Swedish, they are commonly referred to as the sje-sound, based on one of the more common spellings. They have very similar acoustic properties, not dissimilar from the sound of southern Dutch or German ch after e or i, and feature distinct labialization. The International Phonetic Association describes as "simultaneous and ", but this claim is disputed among phoneticians, including at least one former president of the IPA.Peter Ladefoged, The Sounds of the World's Languages.

Features

Features of the voiceless palatal-velar fricative:

• Its manner of articulation is fricative, which means it is produced by constricting air flow through a narrow channel at the place of articulation, causing turbulence.

• Its place of articulation is disputed (see below).

• Its phonation type is voiceless, which means it is produced without vibrations of the vocal cords.

• It is an oral consonant, which means air is allowed to escape through the mouth.

• It is a central consonant, which means it is produced by allowing the airstream to flow over the center of the tongue, rather than the sides.

• The airstream mechanism is pulmonic egressive, which means it is articulated by pushing air out of the lungs and through the vocal tract, rather than from the glottis or the mouth.

Occurrence

This sound has been reported in certain dialects of Swedish, where it is most often known as the "sje"-sound.

• Its place of articulation varies over Swedish regions, and is not agreed upon (see references). It has been variously found to be:

• * velar and postalveolar, meaning it is articulated simultaneously with the tongue dorsum (i.e. the back part of the tongue) approximating the velum (i.e. the soft palate) (like ) and just behind the teeth (like ). However, doubly articulated fricatives are very difficult to pronounce or to hear, and many linguists doubt that they exist.

• * Lindblad describes one of two common variants of Swedish as labiodental with simultaneous velarization and protrusion of the upper lip, which would be transcribed as . (The English sigh of relief "phew!" is probably the closest approximation, resembling the voiceless labial-velar approximant that is used in some varieties of American English.) He does not use the symbol for this allophone.

• * Lindblad describes the second common variant of Swedish as velar. The difference between it and is not clear, but it may have less friction (), or be further forward (), or both.

• * A number of intermediate possibilities between these extremes.

• * Other articulations have been described as well, with no obvious standard emerging.

Consider the following comments by Peter Ladefoged and Ian Maddieson: