Dr. Zvi Margaliot Explains Hi-Fi & Hi-Res Music
With new technologies coming out every day, it can be confusing to understand what all the terms mean. Dr. Zvi Margaliot, a hand and wrist surgeon, enjoys learning about many different topics outside of medicine, and one of his hobbies include listening to classical music. One aspect of music he feels is very important is the acoustics of the music and how it sounds, and in this digital age, it can be easy to download music with poor acoustic quality. He explores what hi-fi and hi-res music is and what different types of formats they come in.
High-fidelity (hi-fi) refers to higher quality of sound reproduction, which is in contrast to lower quality sound reproduction in cheaper audio equipment, or from equipment that was made in the early 20th century. Instruments and recording equipment should allow for reduction in noise and distortion, ideally creating a flat frequency response within the human hearing range.
Frequency response relates to the unchanged intensity of perceived sound within a specified frequency range, which in hi-fi music is generally between 20Hz and 20kHz, which is used as this covers the human hearing range. In classical music, Dr. Zvi Margaliot notes that this is important as it helps listeners appreciate the fine nuances of the music without having to worry about distortion or unwanted background noise. Frequency reduction ensures the listener does not have to worry about intensity fluctuations.
High resolution (hi-res) music refers to audio that is lossless and capable of reproducing the full range of sound from recordings that have been mastered from better than CD quality sources. Dr. Zvi Margaliot explains that this means the sampling frequency and bit depth are higher than that of the standard compact disk (CD), which is 16bit/44.1kHz. The Digital Entertainment Group, Consumer Electronics Association, and The Recording Academy are the ones who formally came up with a definition for hi-res audio.
Dr. Zvi Margaliot states that sampling frequency is how often the signal is sampled per second when converting from analogue to digital, and when there is an increase in bit depth, the signal can be measured more accurately giving a better-quality sound. On average, hi-res audio will have sampling frequency of between 88.2kHz and 192kHz with 24bit. Hi-res music while sounding better does use more storage as the digital audio files are much larger than lower quality audio files.
While MP3 is widely considered the most popular sound format it is not a hi-res audio format. MP3 is defined as a lossy compressed audio file that allows for small sizes and lower quality sound. Lossy-compression is a type of data encoding that uses partial data discarding and data approximation to reduce file sizes. Apple Music and iTunes use another format, AAC, which also makes use of lossy-compression. WAV is the standard used for CDs and hence allows for hi-res audio, FLAC is one of the most popular formats currently that allows for hi-res audio with reduced file sizes compared to WAV, and also allows for metadata storage (such as lyrics, album artwork). An Apple alternative to FLAC is the ALAC format that is iOS and iTunes friendly.
Dr. Zvi Margaliot’s key takeaway points are as follows:
- Hi-Fi refers to high-fidelity audio, which is higher quality
- Hi-Res refers to audio that is lossless and capable of reproducing the full range of sound from recordings that have been mastered from better than CD quality sources
- MP3 files are lossy-compressed, small files
- ALAC and FLAC are the most popular Hi-Res formats