May 27, 2016

Massdrop 101: What Is A DAC?

With millions of songs at our fingertips every minute of every day, it’s easy not to think about where our music comes from—and how exactly it gets to us. The truth is that whenever we play a song on our computer, MP3 player, tablet, or any other device, the music undergoes a complex (but nearly instant) process of conversions, adjustments, and modifications before it hits our ears. One of the most important steps in this audio playback chain is the conversion from digitally stored files into analog signals.
The Digital Revolution
Before internet streaming and other modern technologies came around, everything we heard was stored physically. To save a song or another piece of audio, you needed physical space and a tangible format to store it in (think records, tapes, eight-tracks, and the like). When a signal was recorded, it was saved in analog format, which uses continuously varying signals to represent the fluctuations in air pressure produced by the original sound.
Up until the 1970s, analog was virtually the only way to store audio. Today, the majority of music is stored digitally. Digital format describes a piece of information that is stored in binary using a series of ones and zeros. By storing all of the bits that make up a file in binary, this process drastically reduces the amount of space that files take up, as well as the cost of distributing them.
How It Works
Although today’s world is almost completely digital, our brains still process information in analog. Because we can’t hear ones and zeros, that information has to be converted back to analog before it can be played. Enter the digital-to-analog converter—or DAC.
A DAC uses a series of protocols and technologies to initiate the digital-to-analog conversion. With a combination of hardware, software, mathematics, filters, and a small pre-amplifier to boost the signal, a DAC is able to convert an abstract binary pattern into a physical quantity that can be discerned by our music players.
Virtually every modern device has a built-in amplifier, and the same is true for DACs. Because there are so many features squeezed into our phones, computers, and tablets, manufacturers often cut corners on technologies that are less applicable to a wide audience—especially DACs. Most built-in DACs can adequately convert our music from digital to analog, but to do it well, a separate stand-alone device is necessary. If you want all of those zeros and ones to sound as good as they did when they were originally recorded, you need a high-quality DAC.
Why Get A DAC?
A stand-alone DAC offers more detail, better power supply, and a cleaner, more pleasing sound signature than the miniature versions built into most devices. They’re also capable of playing high-resolution files. While many people are contently listening to MP3 files (traditionally considered to give listeners the most bang for their buck), there are other file formats that can deliver an even better listening experience.
When an MP3 file is encoded, it gets compressed to save space. When the file is compressed, it loses some of its detail and originality, and is then known as a “lossy” file format. Formats like FLAC, Monkey’s Audio, and WavPack are encoded without compression, leaving all of the raw data as was originally recorded—which, in turn, takes up much more space. A high-end DAC is designed to more accurately reproduce uncompressed files, giving listeners a more robust version of what was originally recorded. Some are more flexible than others, allowing users to decode extremely high-resolution DSD files, too. It all depends on the type of DAC.
It should be noted that although a dedicated DAC can enhance our music, the differences will be hard to notice without a decent amplifier and pair of headphones to go along with it. A good DAC is transparent. It converts a digital signal in the most accurate way possible. If the original file sounds bad, it usually won’t sound better just because it’s been converted with an expensive DAC.
What Now?
The best way to find the right DAC is to try one out for yourself. A good place to start is a DAC/amp combo, which offers all the benefits of a DAC and an amp in a smaller package, at a more accessible price. There are a few reasons to try separate components. You may want to understand and have control of each item in your system, and to personalize the sound just for you.
Any questions? Leave ‘em in the comment section below, and someone from the community will be happy to help. Have personal recommendations or a cool audio setup to share? We’d love to hear about them—and see pictures, too! Want to learn more? Read another Massdrop 101 article, “What Is An Amp?”, here: massdrop.com/talk/87/massdrop-101-what-is-an-amp
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Hi i got a stereo with a old car amp play mp3s off my laptop. What stuff can make it sound better
without tons of $ thx :)
need info ask.
do you folks have DAC/Amp combos that support MQA?
Good read!

I have been listening to FLAC files via an external USB DAC from 2010.
Currently I am using a cheap Musical Fidelity V90 asynchronous USB DAC.
As a player I use Audacious on a Linux Mint 18.3 laptop.

I have to note there is one major disadvantage in using streaming audio via USB.
Streaming audio via USB does NOT use any error correction. So for every incorrect package received by the DAC you will hear a glitch/spike like when using vinyl with dirt in the track.
This is especially true for high res audio from 24 bit 96 khz and higher.

My conclusion after 8 years of extensive listening to FLAC files via USB DAC:
1. It is OK for standard lossless 16 bit 44.1 khz material
2. It is useless for high res audio due to numerous glitches caused by non-corrected errors in the USB transfer.

After my holiday I will buy a dedicated audio USB cable to check whether the glitches will disappear!
Does a DAC make sense when streaming music from Spotify on an iPhone with audiophile grade headphones?
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Yep!
Agreed. I have heard visible increase in sonic quality using Tidal but it’s just that their library is limited in the type of music I enjoy so Spotify is the more appealing choice.
I will look into a reasonable DAC.
Thanks again.
I greatly appreciate having this article posted.
DACs are like watches.
If you want something that can tell the time and reproduce music accurately, you buy a quartz watch and an ODAC.
If you want something that is less accurate, but has a nice exterior and some bs marketing behind it, you buy a mechanical watch (think Rolex) and a R-2R DAC (think Schiit Yggdrasil).
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I mean from input to output of the DAC the sound is uncoloured. But sure, at the point of where DACs are today you're balancing marginal trade-offs that are long past the capability of the human hearing.
TheTerriblePuddle
Agreed. The effects of the DAC filter can often be seen as pre-ringing or post-ringing using impulse response test, or square wave test. Whether it is audible is debatable.
Is this not factually wrong statement "Formats like FLAC, Monkey’s Audio, and WavPack are encoded without compression, leaving all of the raw data as was originally recorded—which, in turn, takes up much more space"? In my understanding, FLAC is a compressed file format - but the type of compression is a lossless compression - instead of lossy compression like mp3. Formats like WAV and AIFF or uncompressed file formats.
I innocently searched "hipster glass bottle" because that glass jar looks like it's intentionally placed to make a statement. So yeah, out of the rock I live under, it is indeed a hipster thing to recycle mason jars. On my search, I found an American company called Cuppow and they sell these cool lids for mason jars so you can drink out of them comfortably, the equivalent of adult sippy cups! =D
I have a connection question, please. I have a desktop computer with audio coming through a SoundblasterX Katana soundbar+sub. How would I connect an amp/dac to this setup? USB? Thanks.
webb264
Yes, they'll typically have a USB connection.
Can you tell me what brands these are in the attached photo including both DCA, headphone inpot device, type of headphones shown annd the headphone stand in this photo? Are these available on MasDrop?
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That water bottle tho - any deets on it? ;-)
Drewmon
It's just a tall mason jar. Hipsters are really keen on drinking outta them!
ok- newbie here with a decent analog set up but never really "did digital" except for an Ipod from many years ago. I have a ton of cds and now a growing collection of digital files. I own pretty good headphones but need some advice that is not overwhelming on a stack for my desk. I would like to start pretty basic but good quality and can I do this for less than $3-500? Even better if it is under $250. Ok- thanks in advance for any suggestions.
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THANKS!!!
AaronA58
You got it, buddy! :D