The roots of the arc must not be allowed to come into contact with insulator surface, whereas the middle of the arc channel can do so.

电弧弧根不应接触绝缘子表面，但允许电弧通道的中间部分可以擦过绝缘子。

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The YHT-697BL features HDMI 4K and 3D video pass-through with Audio Return Channel (ARC) and Yamaha's proprietary CINEMA DSP 3D audio to ensure that the system will deliver superior home theater experiences for years to come.

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Supporting HDMI with an Audio Return Channel (HDMI ARC), the Sound Bar plays audio from the TV without requiring additional cables.

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