Analog, Digital, What is the Difference?
The question of analog vs. digital audio is one of the more hotly debated questions in the world of music, film and media today. Does digital sound better? Does analog sound better? Is there even a noticeable difference?
It’s impossible to understand the difference completely without understanding what distinguishes analog audio from digital audio. A full discussion of these terms is best left to your curriculum and discussions with your mentor in the studio. For now, though, here’s a brief explanation of what these two words mean, and the differences between them.
Analog refers to a continuously changing representation of a continuously variable quantity. Digital, however, refers to representing these variable quantities in terms of actual numbers, or digits. The last two sentences seem a bit complex, but let’s try to simplify them with an example. If you consider the numbers 1 and 2 on a number line, there are actually an infinite number of points between 1 and 2. This is what analog represents—the infinite number of possibilities between 1 and 2. Digital, on the other hand, only looks at certain number of fixed points along the line between 1 and 2 (for example, 1 ¼, 1 ½, 1 ¾, and 2).
Can you see the difference? Digital takes a few “snapshots” of the number line, while analog takes the whole line into account.
As another example, think of analog vs. digital as the difference between seeing something in real life and watching it on film. When we see something happen in real life, there are no “spaces” between what we see, so we’re watching it happen in analog. Film, however, is actually a series of still photographs that are taken in rapid-fire intervals, and when we see them in succession, it tricks our minds into thinking we’re seeing a continuous flow of movement. So in a manner of speaking, when we watch the event happen on film, we’re watching it digitally, because we’re watching increments of the event, rather than the whole thing in fluid motion. (Not to be confused with digital video vs. film, which is another discussion completely!)
Let’s bring this idea into audio, music, and the studio. Sound occurs naturally in analog–that is to say, sound occurs in a continuous set of waves that we hear with the human ear. (Think of it as a “wavy” line with an infinite number of points along it.) When we capture that sound in a way that represents all the possible frequencies, we’re recording in analog; when we use computers to translate the sound into a series of numbers that approximate what we’re hearing, we’re recording in digital.
Thus, a purely analog recording would be something that was recorded on tape and produced using manual equipment to mix, master and press into a vinyl LP. A purely digital recording would be recorded on a computer program such as Pro Tools, mixed, mastered and produced digitally, and eventually burned onto a CD as an MP3 or audio file.
The most ironic aspect of the debate about digital vs. analog recording is that nowadays a lot of music is a combination of the two. For example, you might record a song onto analog tape, but mix and master it digitally, or release it on the Internet as an MP3.
So what’s the difference in quality between analog and digital? The idea between digital recording is that our ears and brains technically can’t determine the spaces between the digital values, just like our brains interpret film as continuous motion. However, to many people, analog sound tends to be warmer, has more texture and is thought to capture a truer representation of the actual sound. Digital is felt to be somewhat cold, technical and perhaps lacking in analog’s nuance.
However digital is much cheaper. Recording an album with analog technology can require a whole studio full of equipment, but with digital recording technology, it’s possible to record a whole album in a bedroom on a laptop. And whereas analog technology can wear out or be damaged, digital media can last for an indefinite length of time.
Today many recording artists, both major and independent, record using a mixture of digital and analog techniques. While analog audio does give warmth and a truer sound quality, digital is cheaper to work with and offers more control over the finished product.