Rational and clear information regarding audio equipment is not available today from mainstream audio literature. We only see unnecessary long treatises on high end audio, concentrating on technical descriptions and pointless analyzing of sound nuances, without any clear statements about the sounds fidelity.

Just like external sound cards, USB D/A converters are an integral part of computer audio systems and we would very much like to present our view of their performance. We are trying to avoid long descriptions by organizing USB converters into 3 classes, thus making the information about them simple and decisive. Placing all USB converters into only 3 groups may seem superficial, but after the following explanations the point shall be very clear:

CLASS 1 converters do not change the characteristic sound of acoustic instruments significantly. Trained or professional ears can easily determine the level of distortion caused by the digital to analogue conversion. [lightbox link=”http://www.ap-linux.com/wp-content/uploads/2014/01/class1.png” thumb=”http://www.ap-linux.com/wp-content/uploads/2014/01/class1-320×137.png” width=”320″ align=”left” title=”class1″ frame=”true” icon=”image”]It is always present, but the devices of the class 1 group do not obstruct euphonic lifelikeness during music playback. USB D/A converters in this class should be considered as the best devices available for D/A conversion. Their sound varies from model to model, but all of them share a unique capability to reproduce acoustic music without influence on sound perception, characteristic of a live performance in a concert hall.

CLASS 2. The majority of USB D/A converters are members of this group. CLASS 2 converters lightly distort the analogue signal in a way usually referred to as “digital sound”. It is easily recognized in crescendo passages of orchestral music.[lightbox link=”http://www.ap-linux.com/wp-content/uploads/2014/01/class2.png” thumb=”http://www.ap-linux.com/wp-content/uploads/2014/01/class2-320×137.png” width=”320″ align=”right” title=”class2″ frame=”true” icon=”image”] At a crescendo’s climax the music becomes harsh and tiering, especially for the trained listeners, accustomed to live musical performances. Synthetic music (amplified instruments – electric guitars, pianos, etc.) is not so sensitive to digital harshness. The vast majority of popular music is played on amplified instruments, and this makes the converters in this class popular despite of the mentioned drawbacks.

CLASS 3. Artificial sound, the annoying and unnatural timber of acoustic instruments, make the converters in this class completely useless for serious stereo systems. Although some modern music genres like techno-pop could even profit from distorted sound that the class 3 USB DAC can produce, music connoisseurs devoted to high fidelity should not be interested in digital mish-mash, produced from CLASS 3 converters. [lightbox link=”http://www.ap-linux.com/wp-content/uploads/2014/01/class3.png” thumb=”http://www.ap-linux.com/wp-content/uploads/2014/01/class3-320×138.png” width=”320″ align=”none” title=”class3″ frame=”true” icon=”image”]