D&A Alpha PRO – Digital-to-Analog Converter with Zero-Jitter Clock Architecture

D&A (Digi & Aesth) has introduced a relatively inexpensive ($699) digital-to-analog converter with headphone amplifier D&A Alpha PRO. Alpha Pro was developed on the basis of the flagship ESS Technology ES9039MSPRO chip, it supports signals up to PCM 32/768, DSD512 and hardware decodes MQA.

32-bit noise reduction, proprietary Zero-Jitter Clock architecture and three clock generators with femtosecond accuracy (two for local USB and one VCXO generator for the second phase of PLL synchronization) reduce jitter to a record level of 15 picoseconds!

The SIGMA DAC topology uses summation of the differential signal across 8 channels of the DAC chip for each of the two channels of the device, which reduces the output impedance by 4 times and the noise level by 75%. This guarantees a dynamic range of 133 dB and THD+N at -124 dB.

The digital and analog modules are physically separated using a 4-layer printed circuit board with isolation and independent ground buses. The use of shielded blocks and star power supply wiring guarantees zero crosstalk between the digital circuits and the DAC conversion. Key signal lines are enclosed between the protective layers, forming electromagnetic Faraday cages.

Headphone performance is also exemplary - the D&A Alpha Pro uses 32 discrete transistors across four channels (up to 6W per channel when driving a 32 ohm nominal load) and achieves an output impedance of less than 0.1 ohms, with a total harmonic distortion (THD) of just 0.0001%.