What is hi-fi audio? Understanding high fidelity

What is hi-fi audio, and what do you need to have a true hi-fi listening experience? The music must be recorded in high resolution, and you need a high-quality playback system. Combine the two, and you have hi-fi audio. Read on to learn more about hi-fi audio.

For recorded audio to be considered hi-fi, the sound quality needs to be as close to the original performance as possible. This means no noise, distortion, or other flaws in the original recording.

Digital audio has a superior signal-to-noise ratio, making it possible to record much more cleanly than the analog methods of the past. Some people still prefer the sonic character or "warmth" from the imperfections and distortion inherent in analog audio systems and analog media like vinyl and cassette tapes. However, digital audio is capable of much greater clarity and detail.

When artists and engineers record albums, two main technical specifications determine the audio quality of the digital master recording: sample rate and bit depth. They usually opt for the highest rates available to capture the original performance in high detail, but what do these terms mean?

Sample rate refers to the number of samples the audio waveform takes per second to create the digital signal. Using CD quality as an example, 44,100 samples are taken every second, expressed as 44.1 kilohertz (kHz).

When recording, it's possible to record in higher sample rates, like 48 kHz (used for film audio), 88.2 kHz, 96 kHz, 176.4 kHz, 192 kHz, or even 384 kHz. While these higher sample rates capture more audio information, they also result in much larger digital audio files.

Bit depth refers to the number of amplitude levels captured in each sample in the sampling rate. For example, a CD contains 16-bit digital audio, which can express 65,536 values. A 24-bit or even 32-bit recording is possible, with more detail per sample.

Most audio interfaces and digital audio workstations used in pro studios or home studios can now capture audio in 16, 24, or 32-bit, and sample rates from 44.1 to 192 kHz.

Now that we understand hi-fi audio, it's time to dive into the playback system.

Modern audio systems consist of a digital-to-analog converter, amplifier, and speakers. These can be separate components connected by cables like the common home stereo systems of the '70s to '90s, or they can be combined in a single portable speaker, like modern Bluetooth® speakers. While most serious audiophiles prefer stereo, some home speakers play music in mono vs. stereo, and a high-quality mono speaker can still play hi-fi audio.

Hi-fi audio isn't exclusive to digital audio. High-end analog audio equipment can also produce hi-fi audio, but as mentioned earlier, the signal won't be as clean as digital.

CDs were the first popular digital audio format, using 16-bit, 44.1 kHz digital audio. Of course, CDs have largely been replaced by streaming services, which provide digital audio that varies in resolution. Some have master-quality or high-resolution lossless audio, like TIDAL and Apple Music, while others like Spotify use compressed formats.

Uncompressed files like WAV and AIFF are considered hi-fi quality, equal to CD audio resolution. High-resolution lossless compression formats like ALAC and FLAC also qualify. Some services offer master-quality recordings, meaning they stream the original master audio files recorded in 24-bit and high sample rates like 96 kHz. For these formats, you'll need a digital-to-analog converter capable of handling these higher rates.

In the early days of online file sharing and streaming, the mp3 file format was all the rage. While easy to transmit, store, and stream due to their small size, mp3s are compressed, meaning they sacrifice audio data to achieve a smaller file size. This is done by removing less audible frequencies, so you may not hear the difference between a WAV and mp3 version of the same song. However, once removed, this audio data is gone for good, so playing an mp3 on a hi-fi speaker will not magically make it sound hi-fi. If anything, the better the playback system, the more likely you are to hear the diminished quality in the mp3 file.

For streaming true hi-fi audio, you'll need a service and subscription tier with lossless digital audio streaming, plus a fast internet connection with a generous data allowance to keep up with the larger audio files.

If you still have a CD player and a CD collection, don't banish them to the basement! You can hook up your player to a high-quality amplifier and speakers to enjoy old-school hi-fi audio. This can also work for vinyl enthusiasts.

Hi-fi audio enhances the emotional impact and the overall vibe of music. If you're used to listening to mp3s on laptop speakers or cheap earbuds, you owe it to yourself to try hi-fi audio. Once you hear the difference, there's no going back!

When you listen to hi-fi audio through a great speaker or headphones, you'll hear details you never noticed before. Rediscovering old favorites is a lot of fun, and you'll also hear music exactly as the artist intended.