Of course, good sound is subjective, so the app sets a concrete metric: It attempts to replicate exactly what an audio engineer hears inside a recording studio.

WSJ: Studio Sound to Go | App Happy

The Lennon Bus is a hi-tech mobile recording studio that includes Pro Audio, HD video recording, the NewTek TriCaster 850 Extreme and the TodoCast-provided satellite system.

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Exclusively available on HTC smartphones, Beats Audio provides authentic, studio-quality sound that delivers the spirit of the original recording.

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"GarageBand has given musicians of all talents the ability to create studio quality music at a fraction of the cost of a recording studio, " says Ethan Opelt, Line Manager of Griffin's Audio category.

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"MIDIConnect offers musicians a compact and portable solution to create and edit music on the go, at a fraction of the cost of a recording studio, " said Ethan Opelt, Line Manager of Griffin's Audio category.

ENGADGET: Griffin's MIDIConnect now available at $80 to make beautiful music with your iDevice (video)