What is an audio DAC? Types of DACs and all about analog digital converter
A DAC or Digital Analog Converter is a converter that transforms digital signals into analog signals for listening through speakers or headphones. As you know, the music we listen to today usually comes in a digital format.
What is a DAC and what is it for? The DAC is responsible for providing the necessary information to the headphones or speakers transforming/encoding that same digital information from “ones” and “zeros” to waves.
We may not realize it, but most of us use some sort of digital-to-analog audio converter in our homes. They are built into computers, tablets and smartphones. It is a fundamental part of listening to digital music, as it converts digital information into the analog signals necessary for the human ear to perceive them.
Any device that acts as a source of digital sound, whether it is a CD or Bluray player, game consoles or portable audio equipment, needs a DAC converter.
Traditional amplifiers don’t amplify in digital, speakers don’t play in digital, and our ears don’t listen in digital either: they need analog waves. Without a DAC, our music collection is nothing more than a collection of zeros and ones.
The sounds we hear in our daily lives, such as traffic, people’s voices, etc., are transmitted in the form of sound waves, which travel through the air to our ears in an analog signal. Analog recordings were collected on vinyl records and cassettes, but unwanted noise and the fragility of the format gave way to the entry of CDs, which started the digital revolution at the end of the 20th century.
You should know that digital audio is very different from analog audio. Digital files are usually in the form of Pulse Code Modulation (PCM), and are created by measuring the amplitude of the analog music signal at regular intervals.
The amplitude value is represented as binary numbers and the length of the numbers is usually referred to as bit depth. The time of the measurement intervals is known as the sampling rate.
Digital audio information can be recorded in a variety of ways. samples ratesThe audio DACs, bit depths, codes and formats, but regardless of the differences, the job is done by an audio DAC, which translates the binary information as best it can to recover the original analog recording.
When is an external digital-to-analog converter required?
If every device that plays audio has an internal digital-to-analog audio converter, then why do I want an external one? What happens is that we are talking about sound quality, not whether it sounds or not. An external DAC converter can exponentially improve sound clarity.
Every laptop or desktop computer has a built-in DAC converter to reproduce the sound stored inside it digitally. The problem is that these parts are not of major interest to computer manufacturers, so they use cheap parts and end up being of dubious quality.
Generally, a HiFi DACwill have better audio quality. It generates less noise or distortion when compared to lower quality ones. How good the sound becomes, is directly proportional to the money you invest, at least as far as DACtypes are concerned.
For example, a 300 euro laptop produces an annoying noise when headphones are connected to the included port of the equipment. It has enough volume to notice all distortions thanks to the quality of the headphones. This is when we decided to purchase an external digital-to-analog converter to improve the sound quality of what we hear.
Do I need an audio DAC?
In the following video we can hear the difference using an external DAC converter.
How does an analog digital converter work?
Audio DAC types convert a finite abstract number (usually a fixed binary one) into a physical quantity (such as voltage). An ideal DAC converts the abstract numbers into a conceptual sequence of pulses that are then processed by a reconstruction filter, using some form of interpolation to fill in the information between pulses.
An audio DAC can reconstruct the original signal as long as it has the necessary bandwidth to perform the operation. On the other hand, a conventional practical DAC updates the analog voltage at regular sampling intervals, which are interpolated through the reconstruction filter.
How to use an audio DAC?
It is true that any digital audio equipment requires a DAC converter. That said, not all digital-to-analog converter types are created with the same quality. For example, some may not support the information in certain audio files. Lower quality converters may introduce unwanted noise during playback, as well as some distortions and Jitters.
A Jitter is something like a digital error with time or timing. Timing is vital for digital music. These problems, caused by poor DAC circuits, generate the need to use external circuits to improve the sound when using computers or other digital devices.
Of course, to take advantage of a DAC converter we must use good audio formats. We can’t get miracles when playing a highly compressed MP3, as in 128 Kbps. We perceive the best results when the DAC works with CD quality or higher, which is well compiled in formats such as FLAC, WAV or ALAC (Mac), as well as lossless PCM or DSD formats.
DAC for PC
Most analog digital converters only need to be connected via a USB cable to one of the computer ports. Some types of audio DACs offer other connection options, such as FireWire, which handles audio input and output but does not provide power, unlike USB. There are also sound connection options via XLR or RCA cable.
HIFI DAC for headphones and speakers.
Once we have connected a Digital Analog Converter to the PC, the next step is to synchronize the necessary equipment for the audio output. For music lovers this may mean connecting the best speakers and headphones via a 3.5 mm or RCA cable. This sends the output to an external amplifier to enable the sound experience. Some professional DACs offer the option of XLR connections.
Using a DAC can certainly provide better sound quality, although this also depends on the other equipment you have. Using a good DAC may not make a difference in perception if you do not have good headphones.
DACs for laptop, iPhone, tablets and Android
As mentioned above, a DAC is used to convert digital information into analog sound signals. The audio DAC is low frequency and high resolution while a video DAC has a high frequency and low resolution.
DACs have contributed greatly to the digital revolution. We can mention, for example, long distance telephone calls. Users’ voices are converted into electronic signals by a microphone, then the analog signal is converted back to digital by a DAC, which does a reverse process to the DAC.
The digital information is then divided into connectivity packets so that they can be received. The digital voice is then extracted and assembled, the converter converts it into an analog signal that takes it to an audio amplifier and this to a speaker to produce as faithfully as possible the sound we want to hear in our devices.
Which analog digital converter types to buy?
Analog digital converters come in various sizes and shapes, and offer different levels of options in terms of connectivity and functionality, so you need to think about what you need to use it for and the budget you have.
Portable USB DACs offer portability and affordability. They vary between a size no larger than a USB stick, such as the Audioquest DragonFly Black, or larger devices for the home computer, for example.
Most of the time they draw power from our computers or equipment, so no extra power sources are needed. They have simple connections, headphone inputs and some line output for synchronization with sound systems.
If you need more connectivity and are not concerned about transporting the device, a larger desktop DAC unit may be a good option. These require their own power supply but offer additional audio inputs.
There are also devices designed to work as part of a large home audio system. These have more inputs, such as AES/EBU, and other additional features. They support the full range of high fidelity sound formats and can also offer Bluetooth connectivity for use with phones or tablets.
What is the best DAC on the market?
One of the most frequently asked questions is, if we need an analog digital converter, which one should we buy. We divide the types of DACs into three, according to their quality and price: A, B, and C.
Types of DACs
- A Class A digital analog converter is for those users who are really looking for the best sound quality no matter how much they have to invest. These are used by the most demanding audiophiles in order to seek the highest quality and fidelity.
- A class B converter is sufficient for most hobbyists. Generally, a class B would be the best value for money. Their sound quality and price is lower than Class A DACs.
- Finally, class C devices are better suited to those users accustomed to the portable world or those looking for a simple solution to their connection problems. These DACs don’t have to sound bad, they are just more versatile. These devices can perfectly replace a common sound card and are the best economic option.
We have written an additional article in which we review in depth several of the best DACs on the market in all three classes. You can check our Sound Culture page for information on the technical specifications of these devices, turntables and any other music equipment. In the meantime, we leave you with a video about the process of DAC and ADC devices: