We’ve reviewed a few different products called DACs recently on our website, comparing sound quality, features, and prices. A few of those even give a brief description about what a DAC is, but if you’re new to the world of sound electronics, this still may be new lingo for you.
I know where you’re coming from. When I first decided to set up a home theater system, I was in the same boat. The most common questions I had were “what is a DAC?” and “why do I need it?”. In this article, I will go into full detail about what a DAC is and why it can help you experience the best sound possible, either in your home theater or on the road.
So what is a DAC?
Let’s begin with the most obvious question most people have: what is a DAC?
DAC stands for digital to analog converter. Simply put, it takes the digital format of sound (in the form of 0s and 1s) from your computer or television and turns it into an analog audio signal to be played through headphones or speakers. Some DACs will even take input from a turntable, audio cassette player, or DVD player.
You’ll eventually learn that all computers have a built-in DAC (they must in order to play sounds through the built-in speakers). However, the computer’s hardware runs so much other stuff in the background, it can create interference that lessens the quality of the music as you play. For this reason alone many people will be on the search for the best USB DAC, especially when using a laptop computer.
An external DAC pulls the digital format of the sounds directly from the computer and converts them into a clear analog signal without the background interference.
How does a DAC work?
Any sounds stored on computers or music devices is stored as a series of high and low voltages in the form of 0s and 1s, just like any computer information. Unfortunately, human ears are incapable of hearing 0s and 1s, so we need something called a DAC to convert the information. Only then are we able to hear the music or sounds through our computer speakers or headphones.
What a DAC does, is it takes those 0s and 1s, and through a complex set of resisters on a microcontroller, creates high and low voltage levels that mimic analog soundwaves.
If you’re still lost, here’s another way I like to explain it. It’s like when we use a translator to translate a foreign language into our own native language so we can understand what’s been written, or what someone is saying.
In this case, the foreign language is the 0s and 1s of the digital information, which is being translated (by the DAC) into an audio “language” that we can actually hear.
When do I need a DAC?
As I mentioned before, if you’ve ever played music through your computer, phone, tablet, or television, you’ve already been using a digital to analog audio converter in order to hear the music.
While these DACs function at the most basic level, they usually do the job well enough to not warrant getting an external DAC.
If you’re just a casual listener, and there aren’t any obvious problems with the sounds coming from these devices, you probably don’t need a DAC.
I know, they look really cool, and the idea that any sound coming through them could be better is enticing. While there are plenty of reasons to want a DAC, there are only a few reasons to need one.
The most common reason to need an audio DAC is when the clocks in your current DAC devices are out of sync, causing a phenomenon called “jitter.” This jitter will sound like a warped record on the turntable, or when the tape in an audio cassette is going bad.
Another reason to need to buy a DAC is if there is a lot of noise coming from your source and upgrading the sound card isn’t an option or doesn’t fix it.
What is jitter?
All source devices have a digital clock inside that dictates the timing of content to the DAC (whether it’s the DAC in that device or an external DAC). Your DAC also has a clock. Whenever the two clocks don’t line up in terms of content timing, it results in a distortion called jitter.
To simplify it a little, jitter is basically time distortions that occur when you playback a recording from a digital source. The underlying cause of it can be many things and isn’t always the fault of the device’s DAC.
It could be a distortion that happened when the analog signal was first converted into digital (when it was originally recorded). If this is the case, you may notice jitter only on one song, or in a few select songs. To fix it you wouldn’t need a DAC, you would need a fresh recording.
The sound card could also be at fault. If you can, look into upgrading your device’s sound card. This should eliminate the jitter or noise without having to invest in a DAC.
If, however, it is revealed that the DAC is the cause, or you have a laptop and are unable to change out the sound card, then a quality DAC should help lessen or eliminate jitter.
What is bit depth and dynamic range?
Describing what bit depth and dynamic range can be a little tricky, so bear with me. When any form of audio gets recorded and translated from analog into digital, whatever the bit depth is controls not just the dynamic range of the sound, but also the amplitude.
The dynamic range is the ratio between the quietest and loudest point of a piece of music. So basically, it’s how quiet or how loud the sounds can get.
The higher the dynamic range is, the more room there is for information about the sound, and the more lifelike and livelier that sound is going to be.
If the bit depth is too low, then the dynamic range is going to be too low, as will the amplitude of the sound. And as the sound gets recorded, there is only a limited amount of options for the sound to get recorded. If there’s too much information for the chosen bit depth, distortions in the sound can occur.
To explain bit depth and dynamic range more simply, it’s like a light dimmer. When you look at a light dimmer switch, the distinctive off position and the distinctive on (all the way bright) is what we call the dynamic range of the light switch.
If the switch can move smoothly from off to on (from quiet to loud) without any noticeable breaks or skips, that’s what would be called a high bit depth in audio. However, if the switch only jumps to a few options before hitting the brightest point, then that’s what having a low bit depth would look like.
What’s a good bitrate?
The proper bitrate for playback is something that has been debated amongst audiophiles for a long time. Which is crazy because it is such a small factor in the grand scheme of things.
That said, it can still be important to how well a song or file sounds when being played back. Usually the higher the bitrate (128 kbps vs 64 kbps, for example), the better the sound is going to be. However, the higher bitrate is also going to need more storage space.
The term bitrate refers to how many bits (data) that are processed over a certain amount of time. So in audio, the bitrate for a song or music file is how many kilobits of data that are stored each second.
Now, if you’re only listening to your music through a regular set of headphones (like the ones you get from apple when you buy an iPod or an iPhone), and you’re not using a DAC, then you won’t notice much difference between, say, 320 kbps, 128 kbps, or 64 kbps.
However, if you are using a DAC, which clarifies and balances out the sounds, a song recorded at a lower bitrate will sound off, like when you’ve blown up a low resolution image and you can see all the individual pixels that make up the image. In that case, you will want to make sure your bitrate is at a decent level (128 is a good one to start at). Just know that the higher you go, the more storage space you’ll need, unless you compress the files to fit.
If most of my devices already have a DAC, why do I need another one?
Again, there’s only a few reasons you may need an external DAC. However, sometimes you just want to listen to better quality music. The DACs in your devices only perform on a basic level, so if you want to up the level of your music listening a bit, getting a DAC is a good way to go.
A DAC can come in handy when watching TV or movies in your home. Ever struggle with the sound levels coming from your TV’s speakers? I know I have, especially the times when the speech sounds lower than the music or the action, and you have to keep adjusting the volume. Using a DAC with your TV into a set of external speakers can help balance that sound out, so you’re not having to play with the volume controls as much.
DACs are also necessary pieces of equipment for music professionals like DJs. DJs these days use music stored on some sort of digital device, so in order to play their music (and be paid well enough to play it) it needs to sound amazing. It isn’t enough to use amps and speakers; they will also need a quality DAC to provide the best sounding music their audience has ever heard.
Not all DACS are created equal
If you’ve decided that you want to go shopping for a DAC, I insist that you read a bit further before making a purchase. Why? Because not all DACs are the same. I don’t want you paying a ton of money for a DAC with a bunch of shiny features, if all you want to do is listen to better music through your headphones.
Likewise, if you’re a DJ, or you have a home theater system needing to be setup, a DAC the size of a flash drive is not going to help you.
Also, just because a DAC costs thousands of dollars ore more, doesn’t mean it’s going to be better than one that costs only a hundred dollars.
It helps to do your research. Look at the reviews of the different DACs out there, compare the features and decide what you need in a digital to audio converter. You may find that a $50 DAC does just what you need it to do, while others will prefer the $200 one that gives them all the bells and whistles.
For anyone that takes their music on the road – musicians, DJs, or producers – having a portable DAC can be a great thing. You are already packing a ton of gear, from your computer, speakers, DJ controllers, amps, and more. Adding a big DAC can be cumbersome, especially when a small portable one will do just fine.
You can find ones that are no bigger than a deck of cards, while some are as small as a flash drive.
Portable DACs are also great if you’re travelling and want to listen to some amazing music from your phone, tablet, or laptop. Most times, as I’ve stated here already, the internal DAC that comes with your source device isn’t going to be up to snuff or may just be poor quality. And, on phones, tablets, and laptops, you can’t upgrade the DAC or even the sound card. So the best way to improve your playback is with a portable DAC.
What makes a good DAC?
First, like I’ve said before, what essentially makes a good d/a converter isn’t the one that costs the most money. It isn’t the one that has all of the shiny gadgets and bells and whistles.
It’s the one that makes your life better by improving the quality of the sound you’re listening to or playing. It’s the one that creates a balanced sound that’s warm and free of distortions, noise, and jitter.
A few things to look for when looking for a good DAC:
Plug and play compatibility: You want something that is going to work with any system you plug into, whether it’s Mac, Windows, or Linux. Look for a DAC that doesn’t require any additional drivers or software as well.
Has the features you need: Do you need a simple input and output? Do you require multiple options for each? Do you need something small, or something big for home use? Consider what you need in a DAC and look for these things.
Fits your budget: Once again, a DAC costing $1000 isn’t better than one that costs $50. Consider your budget and how much you can pay for a DAC and go from there.