While Apple’s iPad has gotten quite a bit of attention from musicians, it’s the company’s new MacBook Air ($999) that represents one of the most portable music-production machines to date. For one thing, it’s infinitely more portable than the relatively bulky MacBook Pro: The 11″ Air weighs 2.3 lbs (the 13″ is 2.9 lbs), resulting in a machine you’ll barely notice in your bag (the iPad 2, by comparison, weighs 1.3 lbs). Working in Logic and Ableton was speedy and responsive, particularly when remaining careful about freezing and unfreezing tracks. Both weight and speed are improved greatly by the inclusion of the built-in SSD (64 – 256 GB), and the 1.6GHz dual-core Intel Core i5–based processor ably carries its weight. Complex sessions with plenty of plug-ins and bussing beg for a heftier machine (think of this as a great companion to your main workhorse), but still, for traveling producers, it feels like a breakthrough moment: Once you go Air, it’s tough to go back.