Considerable evidence converges on the plasticity of attention and the possibility that it can be modulated through regular training. Music training, for instance, has been correlated with modulations of early perceptual and attentional processes. However, the extent to which music training can modulate mechanisms involved in processing information (i.e., perception and attention) is still widely unknown, particularly between sensory modalities. If training in one sensory modality can lead to concomitant enhancements in different sensory modalities, then this could be taken as evidence of a supramodal attentional system. Additionally, if trained musicians exhibit improved perceptual skills outside of the domain of music, this could be taken as evidence for the notion of far-transfer, where training in one domain can lead to improvements in another. To investigate this further, we evaluated the effects of music training using tasks designed to measure simultaneity perception and temporal acuity, and how these are influenced by music training in auditory, visual, and audio-visual conditions. Trained musicians showed significant enhancements for simultaneity perception in the visual modality, as well as generally improved temporal acuity, although not in all conditions. Visual cues directing attention influenced simultaneity perception for musicians for visual discrimination and temporal accuracy in auditory discrimination, suggesting that musicians have selective enhancements in temporal discrimination, arguably due to increased attentional efficiency when compared to nonmusicians. Implications for theory and future training studies are discussed.