DAC is an abbreviation for Digital-to-Analog Converter, which is a device that translates digital audio information into an analog signal, which can be played through a speaker, headphones or amplifier. Somewhere in the signal path, every digital audio device must have a DAC. Popular devices that come with built-in DACs include phones, computers, TVs, CD players, and streaming devices. When you find that your built-in converter is less than stellar audio quality, has fewer connections, unwanted noise, or doesn’t have the features you desire, a separate DAC might be of benefit. Buying a separate DAC, however, doesn’t always mean a better sound from any audio system. 

What Is A DAC?

One of the basic components of any digital audio system is a DAC, or Digital-to-Analog Converter.

Digital audio is stored in and sent by using numbers. Digital information is used to represent sound for music files, streaming services, CDs and videos. Your headphones and speakers, however, don’t sing numbers. They require an analog electrical signal.

This is where the DAC comes in.

The digital audio data is then processed by the DAC to convert it into an analog signal. It can then be amplified and played through headphones or speakers.

The general process is as follows:

Digital Audio, DAC, Analog Signal, Amplifier, Speakers or headphones.

A DAC is thus not a “nice to have” in digital audio. If you are listening to digital music via the electronic device, some DAC is already present.

For instance, if you’re playing music on a laptop via wired headphones, the laptop is then rendering the music via its internal DAC. You can connect the laptop to an external DAC and allow the external DAC to do the conversion.

This is important since many people believe that the purchase of a DAC is a prerequisite to a better sound. It is not. 

How Does A DAC Work?

A basic DAC is a circuit that converts digital audio data into an analog electrical signal that is a representation of the original recording.

Music digital is created with samples. The information in each sample is information about the sound at some time. These samples are passed through the DAC and are converted to an analog wave.

A number of technical considerations may impact DAC performance, such as: 

• Sample rate – number of samples per second.
• Bit depth: How much digital information is used to represent each sample.
• Signal-to-noise ratio: Ratio of useful signal to background noise.
• Distortion: Any undesirable change in the signal.
• Frequency: The frequency of the analog signal that the DAC produces.
• After-digital converter circuit: The circuit after the digital converter. 

Modern DACs can support high resolution audio formats, including popular PCM formats as well as DSD, if supported by the device.

However, specifications don’t tell the whole story.

The DAC chip is just a component to a complete DAC device. Other factors that may impact performance include the power supply, analog output stage, clocking, USB implementation, filtering, and overall circuit design.

This is the reason that two DACs can be created based on similar conversion chips but have different designs and features. 

Do You Already Have A DAC?

In most cases, yes.

Most likely you have a DAC that you use daily without any concerns.

DACs are included in many devices, such as: 

• Smartphones
• Computers and laptops
• Tablets
• TVs
• CD players
• AV receivers
• Integrated amplifiers
• Portable music players
• Game consoles
• USB audio interfaces
• Streaming devices

A device with a digital audio input and an analog output for audio requires a DAC in its audio chain.

For example, a DAC could be installed in the headphone port of your laptop. It’s possible that your AV receiver has multiple DACs for the digital inputs. The modern integrated amplifier might have a DAC, enabling you to plug a computer or a streaming input directly into it via USB or optical input.

This does not imply that an additional DAC is a must.

The question is whether the DAC and audio output stage that you have on your existing equipment suit your requirements. 

When Do You Need A Separate DAC?

In some cases, it may be beneficial to have a separate DAC.

Connectivity is a typical explanation. If you need to plug your computer into an amp, but don’t have a USB port, what do you do? The digital audio output from the computer can be connected to a USB DAC, which will give an analog output to the amplifier.

Another reason is noise.

Electrical noise can be audible when listening to a computer’s headphone output. A slight hissing, buzzing or interference may be heard. A separate DAC can alleviate these issues in some cases, by separating the audio conversion and analog circuits from the computer.

A separate DAC is also helpful if your current dac doesn’t provide a great or sufficient headphone output.

For instance, a desktop computer may have a simple headphone port that doesn’t work with all headphones. An external DAC with internal headphones amp will give a better output.

However there are reasons to purchase one too: 

• It requires USB, optical or coaxial digital inputs.
• You need a connection to your existing equipment that you don’t have.
• You need an exclusive headphones jack.
• Noise is audible from your current output.
• Volume control or other helpful features are required.
• Separating a digital audio portion from another component.
• The audio formats you are using are not supported by your existing device. 

In such instances a DAC is not just a tool for the sake of being updated but actually a solution to a specific problem. 

DAC vs DAC And Headphone Amplifier

There’s one aspect of this that can sometimes be confusing, a DAC is not a headphone amplifier.

A DAC is a device that transforms digital audio to analog.

A headphone amplifier boosts and regulates the analog signal to enable it to properly drive the headphones.

Some products are used to do both. These are usually referred to as DAC/amp units or headphone DAC amplifiers.

In the case of high-end headphones, this pairing can be more beneficial than using a DAC by itself.

Think of the weird situation that would be if you plugged headphones into a poor laptop headphone jack.Picture taking a challenging to drive set of headphones and plugging them straight into a poor laptop headphone jack. The DAC might play the music back correctly, but this section of the amplifier might not have enough voltage and/or current.

Both stages can be solved by a DAC/amp.

But, all headphones are not of that style that need a strong amplifier. There are a number of efficient headphones and earphones that can function as effectively as any headphones or earphones connected to a phone, computer or other normal output.

What matters is to understand what restriction you want to address. 

Does A Better DAC Make Music Sound Better?

This is a frequently asked question about DACs.

The truth is sometimes rather than always.

Even very clean and accurate conversion can be achieved by using a modern built-in DAC. If the distortion and noise of your current audio gear are not high, upgrading to a higher-priced DAC will likely make few differences if any in sound quality.

An external DAC will be more of a help if you know you have a problem in your current setup.

For instance you might observe: 

• Audible background hiss
• Electrical buzzing
• Distortion
• Insufficient headphone volume
• Poor channel separation
• Limited digital inputs
• Compatibility problems
• An inconvenient setup

If any of these are not present, an additional investment in a DAC probably will make little difference.

It’s important also not to forget the fact that other components of the system can have a much greater impact on your listening experience. Audio equipment—such as headphones and speakers, room acoustics, placement of speakers, recording quality, and amplifier performance—can all play a role.

In general, it’s better for a new shooter to solve a real-world problem rather than purchase gear just because of its technical specs. 

How To Choose A DAC

If you choose to have one, find out what it will do for your system first, not the price.

First of all, think about your digital source. If you need to connect a computer, then USB might be most useful. Optical could be preferable for a TV. Some equipment also provides coaxial digital connection.

Then consider what it is that you need to get out.

A DAC with a headphone amplifier can be helpful for a headphone setup. RCA or balanced analog outputs might be required with a speaker system.

Compatibility should be considered as well.

Check your own resolution and audio formats. It’s a moot point to pay more for features your music sources aren’t going to use.

Final Thoughts

A DAC transforms digital audio into an analog signal which your audio equipment can recreate. While not everyone may need to purchase a new DAC, it is a requirement for every digital audio system.

Many listeners will be satisfied with the built-in DAC that comes with a computer, telephone, amplifier, receiver, or other product. When you need something special, like enhanced connectivity, lower noise, better headphone output or a dedicated audio system, a separate DAC can come in handy.

There’s not much of an incentive to upgrade to a newer DAC with greater specs if your current DAC is functioning fine and sounds clean.

Rather, examine your entire signal chain and determine what it is you want to improve. The latter helps you make better use of your money and makes purchasing audio equipment a breeze.