Twelve South ( has introduced the US$69.99 BassJump 2, a new version of the portable, USB-powered subwoofer that turns a MacBook Pro or MacBook Air into a travel-friendly sound system.

Like the original, BassJump 2 is powered by a single USB connection and uses proprietary software that blends the sound output of the BassJump subwoofer with the output of built-in Mac speakers for enhanced sound. The new BassJump 2 includes remastered software that delivers greater compatibility and eight more decibels of sound.

Software refinements make BassJump 2 compatible with iMac and Apple Thunderbolt Display speakers, as well as third party USB and headphone-connected speakers. The subwoofer enhances the sound of iMacs and Apple Thunderbolt Displays by adding mid- and low-frequencies for a deeper, fuller sound, according to the folks at Twelve South.