Optional bi-amp circuitry. Baltic birch plywood enclosure with catalyzed multi-layered finish, available in white, gray and unfinished.

可选双功放电路，波罗的海桦木箱体，多层催化涂漆，可选白色，灰色或不涂漆。

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There's also gray birch wood trim--or optional carbon fiber or aluminum--with lots of chrome and brushed metal splashed around the cabin and, naturally, S4 logos everywhere you look.

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The sofa is a dove gray, while the kitchen, built from more stained birch, seems to disappear into the white walls.

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