The oral bass represents the characteristic vocal accompaniment of dance tunes of Lovara and other Vlach Roma (formerly) inhabiting the Hungarian language area [music of the Vlach Roma; khelimaski gjili]. One singer emits sharp, interjectional syllables (e.g. bb bb; bdi bdi; hh hh) in the so-called estam rhythm, where even quavers are accentuated and uneven ones omitted (2/4: ל ♪ ל ♪); sometimes also short quick rhythmic formulae (e.g. bdi dabadaba / 1 quaver + 4 semiquavers) or rhythmic shouts (Hopp! Ža, šej, ža!) are articulated. Against this background, the leading voice engages in wordless syllabic singing to the strophic tune modified by the "rolling technique" (Hungarian "pergetés"), with the fundamental quavers being partly segmented into semiquavers and syncopated.
Playing a role similar to that of the double-bass in the string ensembles of Hungarian "gypsy music", the oral bass is normally performed by men.
Occasionally also Ungrika and Servika-Roma accompany their dance tunes using this vocal technique, which is referred to as bumbázi (Romani) in the Czech Republic and Slovakia, and as szájbőgőzés in Hungary.