dac buying tips
- what is a dac?
- dac types explained
- sample rate vs. bit depth
- mqa explained
- digital jitter explained
- multibit dacs explained
- multiple dac connections (table)
what is a dac?
While most users don’t realize it, the audio quality of most electronic devices is disappointing to say the least. Several factors contribute to sound degradation in electronics. one of them is the digital to analog converter, popularly known as dac. Purchasing an external dac can significantly improve the audio quality of your electronic devices by replacing the built-in dac.
so what is a dac?
Reading: Best headphone dac amp under 100
a dac is a device that converts digital bits (made up of a series of 0’s and 1’s) into analog audio waves.
most integrated dacs are fine for most consumers. However, the quality of a built-in DAC will largely depend on the specifications and price of the device or electronic device. the difference between a built in dac and an external dac is obvious. When using an external dac, the built-in dac is bypassed, replacing mediocre audio quality from your laptop, phone, or computer with better audio quality.
In analog and digital form, sound is stored and transmitted differently.
Most of the sounds and audio we hear started out in the analog category. people clapping, birds singing are captured through microphones and other recording techniques and then digitized. Sound digitization or analog-to-digital conversion converts sound air vibrations into an electrical signal. the electrical signal then stores the digitized value for each point and time. There are several methods for storing digitized sounds. wav, flac, and the more popular mp3 are some of the ways your computer can store and read digital audio.
types of dacs explained
There are several types of dacs available on the market. some work with headphones and others with your home stereo. however, most dacs should work fine with both. here are the types of dacs.
- standalone dacs
- portable dacs
- headphone amps/dacs
- wireless dacs
Standalone DACs can be USB-enabled to connect to your computer or component hi-fi DACs that connect to your home audio system. Unlike portable dacs, standalone dacs will need AC power to function. Some dacs will only have a usb connection, which allows for data transmission and also provides the power needed to run the dac. however, it will be necessary to connect other independent dacs to the mains for them to work properly.
portable usb dacs
portable dacs connect to phones, tablets and others will even double as desktop dacs. Portable DACs typically connect to devices through USB ports. Most portable usb dacs include a headphone preamplifier that is primarily for headphones, but can also be used to connect a computer to a stereo system. Portable DACs can draw power from a computer’s USB port, while some have built-in batteries and are a good companion for DAPs (digital audio players) and phones. For a great portable dac, try the AudioQuest Dragonfly Black USB Dac.
Headphone amp dac combos are undoubtedly one of the most popular dac types out there. This type of dac comes with built in amplifiers that are designed to drive your headphones. some also come with powerful preamps that can double as a dac for your home stereo and headphones. some can even add analog outputs for your speakers and headphones separately. most of the dacs on this list will feature headphone amps.
wireless dacs allow streaming of music from any music system in another location. Wireless DACs currently use Bluetooth for streaming from a computer, tablet, or smartphone. Wireless DACs can also be connected to your computer and send audio signals to a transmitter connected to your amplifier or receiver via RCA cables. The advantage of wireless dacs is that you can move freely while listening to your favorite songs.
sample rate vs. bit depth
The quality of the digitized sound recording will depend on two factors: the sample rate and the bit depth or sample format. the higher the sample rate, the denser the details of a digital waveform, and the closer it is to the original analog waveform. low sample rates result in recordings that poorly represent the original sound. bit depth, on the other hand, determines dynamic range. the greater the depth, the lower the background noise and the higher the audio fidelity. Increasing both the sample rate and the bits in a given sample increases the quality of the recorded sound. however, this will also increase the amount of space used by audio files on your storage device.
after digitizing and storing the audio on your pc, phone or laptop, you need to convert it back to analog audio signals. this is called digital-to-analog conversion. the quality of the digital to analog conversion depends on several factors, and these are the sample rate, bit rate, digital filters and other electronic processes. The sample rate of a converter is one of the essential characteristics of a digital audio system. always choose a dac with a high sample rate. you can always switch to a lower sample rate, but you can never increase it to a higher sample rate. most cheap dacs run at 96khz. however, 192khz is becoming the norm.
mqa is the acronym for Authenticated Master Quality. mqa audio technology allows users to stream studio-quality sound in digital files. This is because mqa manages to fold larger high-quality audio files into small, manageable sizes, but still retains quality when unfolded at the other end. mqa is used by major record labels like warner bros, universal and even sony music. At CES 2017, Tidal became the first to offer high-quality streaming audio using MQA technology.
if you stream your music online, getting a dac or dap that decodes mqa is one of the ways you can experience hi-res audio quality. getting a dac or dap that can’t decode an mqa file will only result in getting a regular resolution file. however, not many cheap dacs have the advantage of handling mqa files. the audioquest dragonfly black is one of the affordable dacs we found that could handle mqa. if something less expensive than this comes along, we’ll let you know.
explanation of digital jitter
jitter is a term used to describe digital audio errors that manifest as noise. jitter can show up as small amounts of distortion buried in the background noise of a digital medium. jitter is measurable, and low levels of jitter will result in quality as original. dacs often use a separate filter chipset that keeps the jitter count low. however, digital jitter is, in many cases, almost irrelevant.
multibit dacs explained
Most of our music is encoded using Pulse Code Modulation (PCM). however, most dacs decode audio using a pulse density modulation (pdm) signal, using the delta-sigma modulation technique. these types of dacs that use pdm are known as delta-sigma. the problem delta-sigma dacs face is that when converting pcm to pdm, they discard original pcm samples. that’s where multibit dacs come in.
multibit dacs are supposed to solve this by decoding an audio signal with more than 16 actual bits, thus preserving the original pcm samples. delta-sigma dacs are typically between 1 and 5 bits, which makes up for loss of dynamic range and high oversampling. schiit audio is one of the audio companies currently offering multibit dacs. its schiit modi 3, currently retailing for $99, is a good example.