A reading offset may be caused by input amplifier overload or DC rectification at the input.

读数偏置可能由输入放大器过载或输入端的直流整流效应所引起。

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Each channel has a channel signal switch, high-performance microphone input amplifier circuit.

各通道设有通道信号切换开关，话筒输入设置高性能放大电路。

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That means that not only the signal input into the amplifier is symmetrical but also the signal output and therefore the connection to the headphones.

ENGADGET: Sennheiser unveils HDVA 600 analog headphone amp, asks for $1,600

In order to fully exploit the sound potential of the HDVD 800 with any audio source, a rotary gain switch at the rear of the unit provides simple adaptation of the amplifier output to the audio input voltage.

ENGADGET: Sennheiser unveils HDVA 600 analog headphone amp, asks for $1,600