The Pioneer A-series speakers feature the OPEN & SMOOTH sound concept to provide seamless and smooth transition between the midrange and tweeter drivers and delivers uniform off-axis frequency response optimized for automotive applications where one or more speakers are often aimed away from the listeners’ ears. Included with the Pioneer A Series 5-1/4 In. 2-Way Component Speaker System are multi-fit installation flexible tweeter mounting hardware that simplify installation and improve acoustic performance. And with the integrated inline crossover network, you increase installation flexibility without the need of an outboard module. All of the Pioneer A-series lineup is voice matched to provide seamless and smooth sound characteristics between the A-series full-range loudspeakers and A-series subwoofers with dynamic, high impact bass that lets you hear and feel the music.