Visual feedback, in which learners visually analyze acoustic speech characteristics, has been shown to significantly improve pronunciation, but extant research has varied widely with respect to the target feature, length of the intervention, and type of intervention. This study presents a comparative analysis of three methods of visual feedback for L2 segmental pronunciation instruction. These methods, all focused on training voice onset time for English-speaking learners of Spanish, differed in duration of instruction (i.e., short and long) and the nature of each intervention (i.e., phonemes presented simultaneously or sequentially). Results show that while all forms of visual feedback significantly improve L2 Spanish pronunciation, evidenced by a reduction in voice onset time, the greatest improvement was found following both longer treatments and a sequential approach. Theoretical and pedagogical implications are discussed
