Analog Metric 5687, User Manual

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[[[[5687 5687 5687 5687 Tube Tube Tube Tube Pre-Amplifier Pre-Amplifier Pre-Amplifier Pre-Amplifier ]]]] Analog Analog Analog Analog Metric Metric Metric Metric
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INTRODUCTION
INTRODUCTION
INTRODUCTION INTRODUCTION
The circuit design comprises of two stages: the first stage uses 12AU7 vacuum tube in
common-cathode configuration which provides moderate gain, minimum noise and high
linearity to the amplified signal; The output stage uses 5687 or its equivalent 6N6-T as
buffer to deliver sufficient power to the load. In additional to pre-amplifing input signal,
this amplifier is capable to drive headphone directly whose impedance is often very low.
The signal paths of this PCB layout is designed in symmetry for both channels. Dedicated
power rails, ground, and signal paths, althogether are taken into considerations so that
all are to minimize the parasitics, cross interference, and influence of RFI.