DAC Overview

This page intends to provide you with a birds-eye overview on the main building blocks of our DAC.

Clean clock, 11.3MHzDirty clock, 11.3MHzPower supply for tube amplifierTube based amplifier, rightTube based amplifier, leftAnalog low-pass filter, rightAnalog low-pass filter, leftD/A converter chip, rightD/A converter chip, leftReclocking signal buffersDigital oversampling filterPower supply analog low voltagePower Supply DigitalInput TransformerReceiverReceiverPhase Locked Loop with VCXO

The design can be roughly partitioned into a digital part and an analogue part.

Digital part

The spdif input signal of the digital source (e.g. a CD drive) must be converted to an analogue signal. The following topology has been chosen.

Analogue part

The output of the DAC chip is a current source. To be able to connect the DAC to an amplifier, the current must be filtered, to get rid of the high-frequency sub-bands, converted to a voltage, and amplified to 2Vrms. This is performed as follows:

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