On onset clusters in Spanish: Voiced obstruent underspecification and /f/

Onset clusters in Spanish consist of an obstruent or /f/ plus a liquid, with the exception of /tl/ and /dl/ which are ill formed in some dialects (tl) and or in all (dl). While this descriptive generalization is uncontroversial, the phonological account of onset clusters has been a topic of debate amongst phonologists for decades now. Most agree that the main factor driving the onset generalization and the well-formedness of the cluster is sonority; yet, it is not entirely clear why /f/ is the only fricative grouped with the obstruents. This paper contributes to our understanding of onset clusters by: (i) presenting additional evidence regarding the sonority of /f/, in support of the proposal in Martínez-Gil (2001); (ii) introducing refinements to the onset cluster generalization/condition (OC) (Martínez-Gil 2001; Colina 2009), most importantly with regard to point of application. The current proposal rests on input and output underspecification of voiced obstruents.