Audio quality: how it works and how to improve the sound on your smartphone

Everyone listens to music and even more easily since the advent of streaming services like Deezer, Spotify, Apple Music or Qobuz. However, the experience varies for everyone depending on the equipment they have, starting with the smartphone and the helmet / pair of headphones used. In order to enjoy your music at best in the context of mobile use, there are small things to check or elements to change to improve the quality of your music. Listening comfort without having to spend miles and cents within everyone's reach.

DAC or no DAC?

First, you have to understand how a smartphone is able to squeeze noise out of your headphones. The phone needs to use a DAC (Digital Analog Converter) for this. Its purpose is to convert digital data (the little 0s and 1s that follow each other) into an analog stream. It serves as a sort of bridge between your audio sources and the notes that will come out of your headphones. This indispensable element is found in a whole bunch of devices that you know like CD players. Moreover, you will notice that some hi-fi systems are composed of two blocks (one for the player, the other for the DAC).

The sound that will come out of your smartphone will depend in part on the DAC it has on board. Manufacturers are making significant efforts on the subject, such as LG, which has notably equipped its V30 with a quadruple DAC Saber ES9218P. On the software side, the Korean manufacturer did not hesitate to add a very customizable equalizer to its smartphone. This allows users to apply the tint they prefer to their favorite tracks (we'll see all of this below when discussing the equalizer).

The LG V30 has a quadruple DAC.

The idea of ​​integrating a high-end DAC is a rather good idea from LG. Indeed, some audiophiles find sound quality to be overlooked by most smartphone manufacturers. To overcome this problem, some do not hesitate to add an external DAC (FiiO products, for example, to be found on Amazon) in order to improve the sound of their smartphones. However, these portable devices have drawbacks: they are battery-operated, weigh a certain weight and require additional connections to operate (smartphone -> external DAC -> headphones/earpiece). That's why a solution like the one offered by LG is probably more relevant in the mobile world.

It's hanging by a thread

Unfortunately, the jack socket is gradually starting to disappear from our smartphones. An important novelty, because in the absence of it, the DAC of smartphones as well as the DSP (the chip managing the sound signal) have been moved to earphones, USB-C headphones and to small jack to USB adapters -C supplied with the new smartphones that are used to connect a wired device. What does this change? And although now, it will be up to the manufacturers of these new headphones / earphones to take care of installing them.

Die-hard audiophiles will all tell you that a well-made wired headset will outperform any Bluetooth headset. The wireless link indeed compresses the sound and we lose de facto in quality. For the majority of users, this transition is not so serious, because today there are very good wireless devices compatible with Qualcomm's Apt-X. This codec guarantees a sound reproduction at least worthy of a CD (16 bits / 44 kHz). Encoding methods, there are several such as SBC, AAC from Apple or even LDAC from Sony which is the Rolls-Royce in the genre. Note that for all this to work, the Bluetooth chips of the smartphone and the headset must obviously be compatible.

Bluetooth 5.0 for its part arrived first on the Samsung Galaxy S8 before gradually conquering several models. This technology allows information to be sent at a higher speed than Bluetooth 4.2 and over a greater distance. On paper, it is therefore possible to enjoy more detailed pieces with compatible headsets.

But whether we are talking about wired headphones or wireless headphones, one thing is certain: it is important for the user to go to a device with a sound signature that they like. As you will have probably noticed, some brands have particularities like Bose and Sony which are known for their headphones with a lot of bass. The other element not to be overlooked is the power of the active (and even passive) noise reduction. The first has the unfortunate tendency to alter the sound reproduction in addition to disturbing some users (the sensation can be oppressive and even cause headaches if used in quiet places).

So take the time to find headphones that will please your ears, whether wireless or with a jack cable.

The source of all pleasures

So far, this dossier sheds some light on hardware solutions. But to make the most of them, they must be associated with the best possible audio sources. Lossless are digitized files without loss of information unlike MP3, which is a destructive compression format. The latter has the advantage of weighing less, but allows itself in return to crush the frequencies, and therefore, to be less detailed.

Uncompressed files thus benefit from a larger sampling than MP3s and are therefore supposed to offer a better sound reconstruction. The first HD files are thus in 16 bits / 44 kHz, which corresponds to CD quality. It is possible to find even more detailed files, even going beyond 24 bits / 96 kHz. These are called High Res files which are identical to what may have been recorded in the recording studio. These files are often in FLAC, ALAC (the rare compressed, but non-destructive formats) or even in WAV.

There are many debates on the real interest of these High Res files. Many people agree that CD quality is more than enough to enjoy his music, because no one would distinguish the difference beyond that and the human ear is unable to hear frequencies not included in 20 Hz and 20 000 Hz. But having an unrestricted file would nevertheless make it possible to enjoy a more natural, fuller sound and a more precise scene. Still, whoever can do more can do less. So, favor the most detailed files over compressed files when possible.

If the idea of ​​retrieving “old-fashioned” music puts you off, there are streaming services specializing in High Res like Qobuz which offers, for a subscription of 24.99 euros/month, access to quality titles. studio. Other services like Deezer even offer CD quality (to be chosen in the application options). For more information, we invite you to look at our guide to the best streaming services and then be able to compare the offers.

On Qobuz, it is possible to retrieve albums in studio quality (24 bits / 192 kHz)

Allow us here a small digression: in spite of all the things stated upstream, it is important to underline that the final rendering of an album depends enormously on the mastering and the final mixing. You can also have fun comparing the different sounds between original albums and remastered ones (at random, those of Pink Floyd or even Led Zeppelin). Some albums will therefore be much more surprising and controlled when others will just be saturated. I warmly invite you to listen to Michael Jackson's album Thriller in 24 bits / 192 kHz, notably available at Qobuz, to get an idea of ​​what a good album is. End of parenthesis.

You have to adjust the shot

Smartphones make it possible to download applications, and in particular equalizers. This software gives access to a virtual mixer as well as a whole bunch of effects (rock, metal, extra bass, folk and so on). They allow you to adjust the sound according to your tastes and to fill in some gaps in the headphones. For example, on the Google Play Store, there is the Equalizer FX application. This one is simple and complete working with certain streaming services. People looking for an audio player with a lot of options can turn to Poweramp. It has the particularity of accepting FLAC and of having some nice features (sound fade, automatic downloading of covers, addition of lyrics, etc.).

Equalizer FX

Poweramp

There are obviously countless alternative solutions, but the FrAndroid editorial staff suggests these two.

When the music is good

Software solutions can improve the sound reproduction of your music, but they will in no way work miracles if the hardware part does not follow. It is therefore important to invest a little bit in good headphones and to use good quality songs. Having a CD-quality media library seems within everyone's reach today, especially with the democratization of offers from streaming platforms.

And for those who want to go to the next level, they will have to turn to audiophile DMPs (we tested the Pioner XP-100R in our columns) or to sedentary Hi-Fi installations. And above all, never miss a chance to explore new musical horizons. Because when the music is good...

Can't decide between Spotify, Deezer or Apple Music? Wondering what the interests of Qobuz, YouTube Music or Tidal are? We help you choose the best streaming service according to your…Read more

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