Analog? Digital? Both? In professional audio, many choices exist, but there’s not enough time to make the wrong ones. We regularly hear claims floating about, often skewed by particular opinions and interests that tend to color underlying simple truths.
The Merriam-Webster Dictionary defines the noun “analog” as being something that is analogous (similar or related) to something else. For example, an analog can be a food product that represents another, such as inexpensive whitefish “krab” intended to replicate more expensive (real) crab meat, or, for you vegetarians, soybeans processed to look and taste like beef.
If you’ve experienced either of these examples, you know that some products are more successful than others in recreating the essence of the original. The audio world is really no different.
But a fundamental difference between processed food and audio, of course, is that a foodstuff analog can only ever be exactly that - analog. In contrast, audio can be reproduced as an analog OR as a digital representation of the original.
When something makes a sound, such as a musical instrument or a human voice, the vibrations produced travel through the air as an analog of that sound. So, we start with an analog of the original, a close representation of the sound source.
If we’re able to accurately preserve the subtleties and nuances of the original movement of the air throughout the audio system, then we have done our job. But how best to do that?
It isn’t just a question of whether it’s better to put together an entirely analog or entirely digital signal path to capture and convey the original sound source.
Both methods offer advantages and disadvantages, and a variety of factors, including circuit design and component choice, can affect how accurately the equipment reproduces the source.
But for all the advances that have brought high-resolution digital audio products to the marketplace, the debate still rages over which sounds “better.” The crux of the matter is how close current digital audio technology, even at high sampling rates and bit depths, can come in replicating full-bandwidth analog audio gear.
Audio—sounds that are within the average human range of hearing generally accepted to cover the frequency range of 20 Hz to 20 kHz - moves through the natural world as an analog signal that is continuous in time and amplitude.
It always starts with analog, such as the lovely voices of Norah Jones (left) and Dolly Parton.
In a digital audio system, a natural sound traveling through the air must be converted after being captured by a microphone.
An analog microphone translates the movements of air on its diaphragm into an electrical signal. That electrical signal must then be converted into a digital signal, a string of zeroes and ones, in order to be transported by, operated on, or stored by the digital audio system that follows.
This is achieved through an analog-to-digital converter, utilizing sampling and quantization.