Mis à jour le 31 March 2021.
While listening to music via streaming platforms is becoming increasingly popular, almost all music services offer a hi-fi or high-resolution subscription to enjoy superior sound quality. With Deezer Premium, Amazon Music HD and the recent announcement of Spotify hi-fi offering listening in CD quality, but also the Qobuz and Tidal feautring albums in Hi-Res format, smartphones and computers have become the preferred source of music for a large number of music lovers.
However, it is essential to ensure that the equipment used to listen to music is capable of supporting high resolution music, especially if you want to listen to Hi-Res digital files stored on a computer, tablet or smartphone. To overcome the limitations of this type of device, the use of a USB DAC or a Portable audio DAC for portable use is strongly recommended. But what exactly is a DAC and how does it bring forth the details, naturalness and dynamics that bring music to life?
What is a DAC?
A DAC is a digital-to-analog converter. That means that its functions is to decode a digital audio signal or music streamed digitally from an online music platform and to convert it into an electrical signal. This converter is often associated with an amplification section to supplyhi-fi headphones or in-ear monitors . These chips designed to convert digital signals to analog are developed by many manufacturers, including, among others, Asahi Kasei, ESS Technology, Texas Instrument and Cirrus Logic. Some audio DACs even have two converters on board in dual mono configuration, meaning that each channel is handled by a dedicated converter. This type of design optimizes the signal-to-noise ratio, minimizes interference and ensures an excellent stereo image for a more spacious soundstage.
Can a DAC be used for Bluetooth transmission?
Using a DAC allows you to enjoy superior quality exclusively with wired headphones or IEMs. While some models are compatible with Bluetooth wireless transmission, the quality of the converter has no effect on the sound since the signal is compressed to be transmitted wirelessly. Bluetooth headphones and True Wireless in-ear monitors therefore do not benefit from the use of a DAC, the codec used for the transfer of the signal is the element to be taken into account.
Why shoud you use a DAC?
In January 2020, the musician and famous audiophile Neil Young critized the MacBook Pro in the press by describing it as having “the sound of a Fisher Price device” and that it was therefore necessary “to use an external DAC to compensate the MacBook Pro problems”. Any digital device capable of delivering sound such as a computer or a smartphone is therefore equipped with a DAC, often very basic, which can easily be replaced by an external DAC to extracts all the details and reproduce the dynamics of music.
Many DACs with an amplification section are specially designed for on-the-go listening. They allow everyone to enjoy the best possible audio quality by easily pairing a smartphone with a DAC. This is done through an OTG cable such as the iFi Audio OTG USB Micro or iFi Audio OTG Type C cable, or by connecting a USB key DAC to a laptop. Some portable DAC models even have a USB-C or Lightning connector to be directly associated with a portable device without going through an additional cable.
Portable audio DAC = portable headphone amplifier
In addition to their ability to support high-resolution digital streams and ensure higher quality playback, many portable audio DACs also have the advantage of acting as portable headphone amplifier . Indeed, some headphones cannot be directly associated with a smartphone because this type of device generally does not have enough power to drive them. Using a portable audio DAC therefore not only makes it possible to take full advantage of the potential of the headphones thanks to better signal handling, but also to drive high impedance models.
Which DAC should you choose?
Depending on the type of files stored on your device, the online music service used or the way you listen to music (nomadic or sedentary), different models of DACs will be more appropriate.
For on-the-go listening with a smartphone or laptop on long journeys by plane or train, a portable audio DAC in key format is a particularly attractive option. Most portable audio DACs adopting this format are capable of decoding PCM FLAC, WAV, WMA, AIFF audio streams up to 24-bit/96kHz. This is the case, for example, of the Audioquest Dragonfly DACs consisting of the Dragonfly Black, Dragonfly red and Dragonfly Cobalt. Easy to transport and connect to a laptop, tablet or smartphone, these key format DACs are an excellent solution for enjoying albums in CD or even Hi-Res quality from online music platforms such as Qobuz. These DACs do not have a battery and are therefore compact and light. They are directly powered by the smartphone or computer.
Many DACs are designed to support audio streams up to 32-bit and 384kHz, or even 768kHz as well as DSD, DXD and MQA for Tidal users. Among these DACs, we find the iFi Audio Hip-dac, FiiO Q3, Earmen Sparrow and Earmen TR-Amp . These models have balanced and unbalanced headphone outputs and include an amplification stage powerful enough to drive demanding headphones with an impedance of up to 600 ohms for the Earmen Sparrow and the iFi Audio Hip-dac. With rare exceptions, these powerful portable DACs are most often equipped with a rechargeable battery to provide a current that is stable and powerful enough to drive demanding headphones.
For demanding audiophiles, there is also a selection of high-end DACs offering performance worthy of a home hi-fi system. These models are bulkier but remain transportable. However, they might not be the best suited for portable use unless they are carried in a backpack or a fanny pack for those nostalgic for the 80s. These audiophile DACs are fitted with a rechargeable battery and can decode PCM streams up to 32-bit/768kHz, DSD256 or even DSD512 and include very high-end components. Usually equipped with balanced and unbalanced headphone outputs, they also benefit from a coaxial and toslink input, which allows them to be paired with other digital sources, such as a CD player or a network player . The Chord Hugo 2 DAC is a transportable model designed to allow you to rediscover all the emotions of music thanks to a natural and dynamic restitution with all digital sources and all types of hi-fi headphones or in-ear headphones .
Some high-end DACs even have a dual mono configuration using one converter per channel (left / right). This is the case with the very efficient iDSD Diablo from the manufacturer iFi Audio, whose design makes it possible to enjoy a particularly spacious and open soundstage. This fairly imposing DAC is made of high-end components protected by an extremely robust chassis with a finish that is sure to catch the eye.