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What is DAC and how it works

We use digital to make the analog world better

What is a DAC? We may not realize it, but every day we make use of a digital-to-analog converter, more or less consciously. A DAC (the acronym stands for "Digital (to) Analog Converter") receives signals in computer language of "0" and "1" and makes them compatible with a system, with a PC, with a smartphone in order to be perceivable by the human ear. This is done with the appropriate cables, which in most cases are coaxial and INTERCONNECT.

It can be integrated, portable, or come to measure more than 40 cm in width, has a considerable number of digital inputs and one to several analog line outputs, and consists of two parts, both of which must be of good quality for the end result to be good. Usually in cheaper DACs the digital part is of very good quality because the costs are low, while the analog part, which requires economic effort, is poor. Especially in the latter are the main differences between a low-end DAC and a high-end one.

The discussion does not touch vinyl or tape lovers, who are natively analog. The commercial explosion of the DAC coincides with the spread of liquid music. The arrival in the 1980s of the CD player did not convince audiophiles because of the shoddy DACs within these early models, which were incapable of producing a sound on par with that of vinyl. Indeed, the early players suffered from jitter (which we might define as a time lag between the transmitted and received signal). It was at this time that manufacturers and buyers began to attach special importance to this tool, which became increasingly important in its stand-alone, non-integrated form and, over the years, also more affordable. Ultimately, to answer the initial question "What is a DAC?", we could answer it this way: the DAC replaces the source to decode the digital audio signal, performing this operation in an optimal manner.

marantz dac what is it

What to know when buying a DAC

The DAC is not only important, but essential, if you want to have maximum performance from your system. Its two main characters are signal-to-noise ratio and THD(Total Harmonic Distortion).

Signal-to-noise ratio is often abbreviated by the English acronym SNR(Signal to Noise Ratio) or S/N also in Italian usage. It is a numerical quantity that relates the power of useful signal to that of noise in any information acquisition, processing or transmission system. In the field of Hi-Fi, the signal-to-noise ratio is one of the fundamental, though not the only, parameter of merit in evaluating the performance of a system with regard to sound cleanliness.

There is also the SINAD, conceptually very similar to the SNR, which along with noise also includes the distortion generated by the circuit; it gives a more accurate assessment of the degradation assumed by a signal due to the non-idealities of the equipment it passes through. Not surprisingly, it has been verified that a DAC powered by a battery works much better than when the same one works thanks to a power supply.

Harmonic distortion and sampling in the DAC

A measure of the harmonic distortion present in a signal is the ratio of the sum of the powers of all harmonic components to the power of the fundamental frequency. Distortion factor, a closely related term, is sometimes used synonymously. In audio systems, lower distortion means that the components of a loudspeaker, amplifier, or microphone or other means produce a more accurate reproduction of an audio recording.

When it comes to digital, one must also be careful about sampling. Sampling is, to use a metaphor, taking a recording and taking many "photos" of it at regular time intervals. These photos are taken on multiple levels; the more levels we have, the less time there is between photos, so the less quality we will lose. The number of bits in a DAC is just the index of how many levels I have; the sampling rate is the index of how fast the photos are being taken (the minimum acceptable is 24 bits at 192 kHz). Beware, however: there is no incontrovertible technical data to define which device is better. They all suffer or enjoy the effects of unmeasurable factors, which may, for example, be good design or poor arrangement of components.

The Ricable cables for your DAC: coaxial and INTERCONNECT. USB coming soon

There are multiple solutions for connecting the DAC to the source or amplifier. Here are the ones used in most situations. In the first case there are digital coaxial cables, which carry the digital audio signal before it is converted to analog and then amplified. Although they have the same connectors as INTERCONNECT RCA cables, they have an entirely different function.

invictus coaxial

The most common usage scenarios are the connection between a digital source such as a CD player or PC (with the help of an interface) and a DAC. The series are the canonical ones Ricable: starting with the entry level Primus, moving on to Magnus e Dedalus, and concludes with Invictus. Rather similar are the optical cables; these, however, are less musical and more suitable for other areas of use. The last type of cable is the USB cable, especially in cases where the connection is made between a DAC and a PC. Ricable is working hard on an optimal solution in this regard, and after the period of research and development, it will launch a product on the market that will guarantee its customers a connection with all the trappings.

Joining the DAC and amplifier instead are the cables INTERCONNECT, which are needed whenever an analog signal, in Stereo mode and with an RCA connection, passes from one device to another. Once again, the Ricable offering is differentiated into the series Primus, Magnus, Dedalus e Invictus.

One thought on "What is DAC and how it works"

  1. enzo he said:

    thanks for the explanations but i didn't understand if the dac can really improve the signal of music broadcasts from pc ( youtube, jazz radio etc), i mean, if the broadcasts have a low quality how can the DAC improve them? In fact you know what I read you talk about 24 or 32 bit, boh, I am confused, thanks for the answer

    1. Ricable he said:

      Hi Enzo, obviously the better the source file the better the leap in quality you will have with a good DAC, however, even with streaming playback there is a marked improvement over an integrated sound card.

  2. Rino he said:

    I have some curiosities related to home theater. Having a TV with optical audio output and an older generation NAD AV711 amplifier with Dolby Digital 5.1, but no optical inputs, I am forced to use a DAC to connect the TV output to the amplifier. Since I know that the digital signal transmitted through the optical cable contains Dolby Digital/DTS 5.1 encoding, is this encoding lost in the conversion to an analog signal? Is the output signal a simple stereo signal and does the amplifier process it to produce the surround effect or does it arrive already encoded and the amplifier just decodes it and distributes it through the various channels?
    Thank you in advance for the clarification.

    1. Ricable he said:

      Good morning Rino, if the DAC is stereo, the signal comes out stereo and then, if the amp has an audio processor, it virtualizes the multichannel. Have a good day.

  3. Alexander he said:

    Good morning,
    I am writing to you because I am a bit confused about the topic of DACs built into the various parts of the audio playback chain.
    Considering that I own a Cambridge amplifier with built-in DAC, I would like to ask you kindly what would change between pairing it with a blu-ray player without DAC or a blu-ray player with built-in DAC; is there a difference or since the aplifier is equipped with DAC would there be no difference?
    Thank you.

    1. Ricable he said:

      Good morning, the DAC in your chain can only be one, so in your case you must decide whether to employ the DAC in the Blu-Ray player or the one built into the amplifier. Obviously the choice will have to be made on the better of the two. In the case that he decides to employ the DAC of the player, it will come out of the player in analog to enter directly into an analog input of the amplifier, on the other hand if he chooses the one of the amplifier, it will come out in digital from the player (coaxial recommended) to enter into the DAC integrated in the amplifier.

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