Recent advances in sound engineering have led to the development of so-called streamlined music designed to reduce exogenous attention and improve endogenous attention. Although anecdotal reports suggest that streamlined music does indeed improve focus on daily work tasks and may improve mood, the specific influences of streamlined music on cognition and mood have yet to be examined. In this paper, we report the results of a series of online experiments that examined the impact of one form of streamlined music on cognition and mood. The tested form of streamlined music, which was tested primarily by listeners who felt they benefited from this type of music, significantly outperformed plain music on measures of perceived focus, task persistence, precognition, and creative thinking, with borderline effects on mood. In contrast, this same form of streamlined music did not significantly influence measures assessing visual attention, verbal memory, logical thinking, self-efficacy, perceived stress, or self-transcendence. We also found that improvements in perceived focus over a 2-month period were correlated with improvements in emotional state, including mood. Overall the results suggest that at least for individuals who enjoy using streamlined music as a focus tool, streamlined music can have a beneficial impact on cognition without any obvious costs, while at the same time it may potentially boost mood.