DAC

The design of an external DAC (Digital to Analogue Converter) with an audible performance that can better the internal DAC in a CD/DVD etc. player has for years been a complicated exercise for the analogue audio engineer. The subsequent end result was therefore either expensive or not much better than existing internal DAC circuitry. Combining digital and analogue tracks and components on the same PCB, plus using legged components for operation in high frequency parts of the circuit is fraught with dangers such as oscillations, interference, noise, etc.

In order to solve these problems and control the manufacturing cost we separated the digital design aspect from the analogue one. Our digital PCB follows high frequency design parameters and is made up of surface mount components, which do not suffer from many of the restraints that legged components put on a digital design. Performance wise, our digital PCB with surface mount components will outperform an equivalent circuit made up of legged components, and by quite a large margin.
Additionally, it only cost a fraction to manufacture compared to its legged components equivalent. An important factor that is reflected in our low retail price.
The analogue stage is less than 2 centimeters away from the DAC chip. This reduces the chances of long PCB tracks picking up cross channel interference etc, which would otherwise lead to audio signal contaminations.
The LINE output sockets are right next to the analogue output IC, further reducing any chances of audio signal contaminations.
Our Control circuit, internal power supply, and headphone amplifier are all on a separate PCB that is well away from the digital PCB. Again a safety measure to eliminate any digital signal interfering with analogue signals.

The headphone amplifier does not share any analogue components with the Line output stage and only sends audio signals to the headphones. This removes any chances of the headphone amp circuitry interacting with the Line output circuitry.
Our internal power supply consists of 4 separate supply lines. They are: digital psu, analogue psu, control psu and headphone psu. Separate voltage regulators and reservoir capacitors help to isolate each part of the DAC from mains and ground track noises. It also ensures that power supply load variations in one part of the circuit do not upset the power supply requirements anywhere else.

By following these strict design rules we have managed to produce a DAC with performance figures that are hard to beat at any price. At the same time, it helped us to produce a world beating DAC at a fraction of the price of any other DAC coming anywhere near the performance of the TC-7510.

Specifications;

• Frequency Response: 2.0HZ -20KHZ, 10.25dB

• Amplitude Linearity: >1.06d8

• Channel Separation; >I00dB@:lkHZ

• Line Output Signal to Noise. Ration: >130dB

• Total Harmonic Distortion: <0.00l5%@ lkHz

• Phase Linearity: +/-0@;20KH2l

• Digital Input: 96kH2; Consumer Standard SPDIIF

• Maximum Jitter (HP): <50 pico seconds RMS, using selected low jitter Crystal

• 0va-Sampling Rate: 8:*(352.8-kHZ)

• Resolution Capability: 24bit

• Digital Filter: 82dB

• Power Supply; DC 1.2V

• Absolute Polarity: 0 or 180 degrees switchable

• Digital Inputs:
  1x Coaxial; 75 ohms RCA
  2 x TOSLINK Fiber optic; EIAJ Standard CP-340/RC-5720,660nni typical wavelength.

• Dimensions: 245 (L) X 114 (D) X 37 (H)