Smart & Connected Life Connected Car Tech 61 61 people found this article helpful Car Audio DAC: From Analog to Digital and Back by Jeremy Laukkonen Writer Jeremy Laukkonen is tech writer and the creator of a popular blog and video game startup. He also ghostwrites articles for numerous major trade publications. our editorial process Facebook Twitter LinkedIn Jeremy Laukkonen Updated on October 31, 2019 Katja Kircher / Getty Images Connected Car Tech Android Auto Apple Carplay Navigation Tweet Share Email Whether you're still holding on tight to your CD player, you’ve made the switch to a mechless head unit, or your listening habits fall somewhere in between, your entire car audio experience really hinges on a component you may have never even heard of. This component, the digital to analog converter (DAC), is responsible for taking digital information stored on CDs and in music files, and converting it into something that can be played over your car speakers. The one exception to this rule is conventional AM/FM radio, which starts off with an analog signal. Every other audio source in your car is stored in some type of digital format, whether that be on a physical CD or as bits and bytes on a flash drive. In order to translate that digital information into an analog signal that’s capable of driving your speakers, and thus create music you can actually listen to, it has to pass through a digital to analog converter. So what, exactly, is a DAC, and how important really is this ubiquitous little piece of technology? The answer to the second question is easy: having a good car audio DAC is absolutely indispensable in any modern car audio system. The answer to the first question, however, requires a little bit more in terms of explanation. From Analog to Digital and Back Again Music, and other forms of audio recordings, all start out as analog signals, and at one time they were also recorded in analog formats. Records and audio cassettes are both examples of analog media formats, but the modern audio recording has since moved into the digital realm, first with CDs and later with digital files like MP3s. The purpose of storing and transmitting music and other audio recordings in digital formats is primarily an issue of storage space and convenience. A compact disc can store more audio data than a record or compact cassette in less space, and digital storage media like a hard drive or flash drive can store an even greater amount of audio data than that in the form of MP3s and other files. After an analog audio recording has been converted into digital data, it’s of little use to us until it’s converted back. While in a digital format, the signal is abstracted as binary data that can’t drive a speaker or create an audible sound on its own. In order to do so, it has to be passed through a digital to analog converter. Digital to Analog Conversion Virtually every audio device that relies on digital media contains a digital to analog converter. That includes everything from your iPod to the head unit in your car. In-home theater contexts, you can even find standalone DACs that are designed for use with CD players that either don’t include a DAC or have a digital output. These standalone units are typically higher in quality than most built-in DACs, so they are capable of more faithful reproductions of the original analog signals. Although there are different types of DACs, they all perform the same basic function: converting abstracted digital data into a physical signal that can then be amplified and used to drive loudspeakers. This is usually accomplished by converting the digital information into a corresponding set of stepped pulses, which is then smoothed out via interpolation. The quality of the resulting signal is highly dependent on the way the DAC goes about accomplishing this, so the same digital information can provide remarkably different quality and flavor of sound depending on the DAC that it’s passed through. Most digital to analog converters are contained on integrated circuits due to size and cost constraints, but there are also DACs that use vacuum tubes to produce a warmer, more detailed sound. Portable Car Audio DACs and Head Units Most portable DACs are designed for use with laptops, and they essentially offload the heavy lifting of converting digital music to an analog signal from computer software to a physical device. This type of portable DAC can be used in your car as well, if you have an audio source that is capable of outputting via USB and your head unit has an analog input. The other way that DACs come into play in cars is that some head units include digital inputs, typically in the form of a USB or proprietary jack. The way that this type of connection works is that it allows you to plug in your iPhone, tablet, or any other MP3 player and offload the processing to the head unit, rather than relying on the DAC in your phone or another device. Do You Need a DAC Component in Your Car? If you want the best possible sound quality, and you've already upgraded your head unit, amplifier, speakers, and maybe added other components like an equalizer, then adding a DAC can help push your sound quality to the next level. Even if you just have a decent factory car stereo that sounds pretty good, you can benefit from adding a portable DAC like the Apogee One that sits between your phone or portable music player and your car stereo. It's also important to remember that you don't have to buy an expensive portable DAC to experience better sound. Your car stereo probably has a decent DAC built right in that's designed for use with car speakers. Instead of using an analog connection like an auxiliary jack to plug your phone or music player into your car stereo, consider using a USB port. If your car stereo has a USB port, or you're willing to upgrade, you can feed digital music files directly to the stereo. This allows the built-in DAC in the head unit to do the heavy lifting instead of the DAC in your phone or music player, which will typically result in better sounding music.