What are DACs(Digital to Analog Converters)?

What is a DAC (Digital-to-Analog Converter)?

Simply put, a DAC is a digital to analog converter, a device that converts digital signals into analog audio signals(digital to analog conversion).

Digital music is typically stored in a computer or mobile device in a binary number format, which is a series of 1s and 0s. These digital signals cannot be directly played through an analog system, such as an active speaker, because amplifiers typically operate in analog philosophy and require varying voltage levels to produce sound.

To convert digital signals into analog signals, a DAC takes in the digital audio data and converts it into an electrical waveform that can be processed by analog amplifiers. The DAC achieves this by using algorithms to interpret the digital data and generate an analog representation of the original audio signal.

In essence, the role of the DAC is to act as a translator between the digital audio source and the analog system, allowing users to enjoy Hi-Fi audio playback.

If my device has an RCA/3.5mm output, do I already own a built-in DAC?

Yes.

Why bother getting a separate DAC?

A separate DAC typically offers better quality than a built-in DAC because it is designed specifically for the conversion, while built-in DACs are often a secondary feature of another device such as a smartphone or laptop. (The DAC built-in In dedicated audio devices like DAPs, cd players, Wi-Fi streamers, on the other hand, could be of good quality.)

The components in a DAC circuit can significantly impact the sound. There are higher quality components in dedicated DACs, such as better DAC chips, power supply, output stage, capacitors, resistors, PCBs, coils, and transistors. Using higher-quality components can offer better dynamic range and lower distortion, provide better noise isolation, a cleaner AC/DC, and fewer unwanted interferences, which offers a stabler operating environment and a more accurate output. All these contribute to lower distortion and give a more faithful reproduction of the original audio signal.

Furthermore, high-end digital to analog chips and advanced circuit designs adopted by dedicated DACs usually incorporate more complex conversion algorithms and signal treatments, including upsampling, oversampling, and filtering techniques, which can provide a more accurate conversion of the digital signal to analog, resulting in more transparent, detailed, natural and dynamic sound.

We recommend getting an audiophile-grade DAC whenever possible. Because why wouldn't you want to unleash the full potential of your expensive speakers or headphones after spending your hard-earned money on them? If you haven't purchased the speakers or headphones, get them first. Then the next step is the DAC. It provides a more immersive listening experience.

Two different types of separate DACs

There are two types of separate digital-to-analog converters: desktop and portable. Desktop DACs are larger and designed for home audio use, while portable DACs are smaller and intended for use on the go.

Desktop DACs are typically designed to be powered by AC. As a result, they often incorporate larger power supplies that can provide a more stable and consistent output. It allows desktop DACs to use higher-quality components that may require more current and can result in better performance.

On the other hand, portable DACs are designed to be powered by a battery or USB connection from a mobile device. It requires the use of more energy-efficient components, and as a result, portable DACs may sacrifice performance compared to their desktop counterparts. However, portable DACs offer the convenience of using them on the go, and they can still provide significant improvements over the built-in DAC of a mobile device. They are usually integrated with the headphone amplifier and can come in handy when it comes to using headphones on the go.

The choice between a desktop or portable DAC will depend on individual needs and priorities, such as the desired performance, portability, and power supply requirements. When using at home with a cd player, a high resolution stereo system, a pair of powered speakers or a home theater audio system, the desktop DAC is the preferred choice.

If I am using wireless earbuds, can I benefit from using a external DAC?

Unfortunately, TWS earbuds already have their own integrated DACs inside and do not have any analog inputs. So it is not possible to connect an external Hi-Fi DAC to it for the purpose of great sound.

What is a USB DAC? Is it a different type of DAC?

It is a DAC that includes a USB input for connecting to a computer or mobile device, while a non-USB DAC does not have this capability. More and more DACs are incorporating USB inputs (the ports can be USB-C, USB-B,  USB-A, or lightning) because of the widespread use of computers and mobile devices as a source of audio. It allows for a high-speed connection that can transfer large amounts of audio data quickly and efficiently, so they often support a wider range of sample rates and bit depths, allowing easier bit-perfect sample rate playback of Hi-Res files. This makes it an ideal interface for connecting the laptops and smartphones to an external DAC and is becoming a common feature. For example, a portable DAC with USB-C and lightning inputs can suit the need of Android and Apple phones at the same time. 

Which DAC chip is the best?

There is no one "best" DAC chip that suits all applications, as different DAC chips are designed for different purposes and have different features and performance characteristics. In addition, the performance of a DAC chip is influenced by other components in the circuit, such as the power supply, the analog output stage, and the signal path.

Some popular Hi-Fi DAC chips for audio applications include the ESS Sabre and AKM Velvet Sound series, which are known for their high resolution, low distortion, and low noise performance. Some other popular DAC chips are from Burr-Brown (now part of Texas Instruments), Wolfson (now part of Cirrus Logic), Cirrus Logic, and Analog Devices. These chips are commonly used in Hi-Fi audio applications due to their ability to achieve high resolution and accuracy, as well as their suitability for oversampling and noise shaping techniques that can improve the signal-to-noise ratio. Each manufacturer may have their own unique implementation and additional features, but the core architecture of their DACs are mostly based on Delta-Sigma.

Ultimately, the choice of which DAC chip to use will depend on the specific requirements of the application, such as the desired performance level, features, and cost. It is also important to consider the overall system design and the quality of other components in the circuit to ensure that the full potential of the DAC chip is realized.

Are there DACs that does not use off-the-shlef chips?

An R2R DAC and a FPGA DAC are both examples of custom-designed digital-to-analog converters that do not use an off-the-shelf DAC chip

An R2R, or ladder, architecture is typically designed by building a ladder network of precision resistors, which are precisely matched and trimmed to achieve high accuracy and linearity. The resistor network is then connected to a switching matrix, which selects the appropriate combination of resistors to generate the analog output signal. The design of an R2R DAC can be challenging, as it requires precise matching of the resistors and careful attention to the layout and signal routing to minimize noises and interferences.

A FPGA DAC is designed using the field-programmable gate array (FPGA), a programmable hardware chip to perform the digital-to-analog conversion using a custom algorithm. An FPGA DAC can be highly flexible and customizable, as the algorithms and signal processing stages can be optimized for the application's specific requirements. However, achieving great performance with FPGA DAC is not a easy task. It requires a deep understanding of architecture selection, DSP algorithms, FPGA structure, as well as expertise in system-level integration and optimization.

Both R2R and FPGA DACs that do not use an off-the-shelf DAC chip can offer high performance and flexibility, but they require more design effort and expertise compared to using a pre-built DAC chip.

What DACs do we recommend?

We carefully select and recommend high-quality DACs. All DACs on our site can provide our customers with the best possible audio experience at their price range.