10 Best USB DACs | March 2017
- does not require additional power
- includes optical digital adapter
- overamplified for headphones
- wolfson 24-bit converter
- impressive output from any device
- input selector resets when shut off
- rubber feet for stability
- auto shutoff when computer is asleep
- produces some audible buzz
- can bypass a computer's sound card
- selectable gain design
- difficult to use with windows 10
- analog and coaxial digital outputs
- built-in 3db bass boosting circuit
- strong and clean headphone output
- four converters per channel
- ultra-low distortion
- eliminates jitter and noise
- 32-bit sabre driver
- award-winning design
- extremely simple but effective
Babies love to play peek-a-boo. One moment you're there, and the next, you're not. Then, you return, maybe making a silly face. It's a game that hooks into the binary nature of our world, of our perception, which, believe it or not, is the very root of computational algorithms. In the case of something like audio rendering, the more expansive and specific the logic, the better the sound quality.
Think of it this way, when you record an acoustic guitar through a microphone and onto an analogue tape deck, that microphone translates the sound of the guitar into an array of electrical signals. Those signals, when magnetized, imprint on the tape with an equally expansive array of magnetic forces, creating a nearly perfect simulacra of the sound originally produced.
To distribute that magnetic signal, those audio masters have to be digitized, a process by which each element of magnetic force meets with a corresponding binary representative. Sound cards in your electronic devices read those binary representatives and recreate their original sounds by way of a digital-audio converter, or DAC. The only problem is that along each step in the pathway, you sacrifice sound quality.
If you wanted to own an organized representative binary file for each sound produced in a recording studio, your music files would be enormous. The best you can do is to get your hands on what's called lossless audio, the file sizes of which average about ten to fifteen times those of the audio you can download from, say, iTunes.
That's because hard drives, CDs and servers alike operate on finite amounts of space, so the more songs Apple or anybody can fit on their servers, the more money they stand to save. To get to this point, they independently determine which chunks of that representative binary map you don't really need to hear. It'd be like having an engineer from one of these music distributors come to your house at dinner time and remove the parts of your meal they figure you don't really need to enjoy. It's manipulative, and it's downright insulting.
Now, your computer already has its own DAC, but these are designed with the assumption that you're not interested in lossless audio, so their quality is severely limited. What a USB DAC can do, by comparison, is take your finest digital audio signals and convert them back into analogue voltage with more nuance and processing power than the majority of sound cards on the market. The result is a truer audio experience than is otherwise possible.
Take A Bite Out Of Your Files
We touched briefly above on the music industry's compression of audio files for easier storage and distribution. The evidence of this compression is most visible when comparing the bit rates of different files. For example, if your music library consists of files downloaded from iTunes, the majority of them is probably going to come in at about 128 kbps, or kilobytes per second.
By comparison, CD quality is at least 320 kbps and lossless audio files often linger around 1,500 kbps, more than ten times the amount of data stored per file. Studio masters reach even higher, often breaking 2,000 kbps. Now, to be fair, a bit of this compression eliminates things you either can't hear, or that you don't want to hear, like frequencies below and above human hearing that studio tape can pick up or like strange room noises left over from the studio space itself.
If you use iTunes, you can see the bit rate of all your files just by right clicking on any one of them and choosing 'get info,' then the 'file' tab. The great likelihood is that, if you're reading this, you probably have a decent amount of high quality audio files on your computer already. If, however, you see that most of your files are around 128 or 192 kbps, an outboard DAC isn't going to make very much difference in your life unless the DAC on your sound card happens to be fried.
Still, I'd recommend picking one up and also going out and investing in higher quality files for your favorite bands. The added dynamism and depth will render some songs almost unrecognizable from your current understanding of them.
Conversion For Encryption
You couldn't have digital to analogue conversion without first having analogue to digital conversion. This is not a chicken/egg scenario. Like a tremendous amount of technology in the music industry, digital recording began in the once-exciting world of telephony.
For this development we can thank a British engineer named Alec Reeves, who first came up with a system of pulse-code manipulation (PCM) in 1937. The technology could render a human voice into a kind of binary and transmit it via telegraph. The system, like so many great telephonic inventions, saw its first use during wartime, as Allied soldiers used it to convey complex, encrypted messages.
To decrypt these messages, soldiers used the first DAC units known to man, which were simple reversals of the technology used to encrypt the messages in the first place.
PCM recordings found their way onto a litany of media over the ensuing 40 years, becoming an integral part of the music industry by the late 1970s, just before the release of the first compact disc prototype, a joint effort between the companies Sony and Philips.