Individuals with hearing loss often struggle to hear the vocal tracks in songs, particularly in more current music where the vocals are typically quieter than the rest of the track. Recent research suggests that increasing the vocal levels can make music more accessible for people with hearing loss.
Typically, professional recording studios record separate tracks for each instrument. Sound engineers then adjust the levels of each track independently to create the final mix for distribution.
A study conducted by researchers at the University of Oldenburg in Germany examined music from previous decades and found that the lead vocal track has gradually become quieter relative to the other tracks. The difficulty in hearing the vocals varies by genre, with rock and metal being more challenging compared to country, rap, and pop.
The research employed a measurement called the “lead vocal to accompaniment ratio” (LAR) to assess the ease of hearing vocals in different songs.
“Our research demonstrated a notable decrease in the LAR, from around 5 decibels in 1946 to approximately 1 decibel in 1975, after which the LAR remained constant,” explained Karsten Gerdes to the American Institute of Physics (AIP).
The change in mixing levels over time could partly explain why older individuals often complain about not being able to hear the vocals over the bass in recent songs. However, age-related hearing loss also contributes to the difficulty in distinguishing the vocal track.
The same research group, led by Kai Siedenburg, has now published a subsequent study demonstrating that individuals with hearing loss prefer songs with louder vocal tracks or higher pitches. While hearing aids are not primarily designed with music appreciation in mind, one potential solution could be to remix tracks in a way that enhances the prominence of the vocals.
In the study, the researchers played music with varying levels of vocal and instrumental tracks to participants. They found that people with hearing loss, on the whole, favored a different mix compared to those with normal hearing.
“Generally, individuals with hearing impairments experience reduced frequency selectivity and impaired level perception,” explained Aravindan Benjamin to the AIP. “They tend to prefer louder levels of lead vocals compared to individuals with normal hearing.”
To some extent, listeners can adjust the level of different tracks using their sound system. However, another option could involve music producers providing special mixes for those with hearing loss, utilizing the original recorded tracks.
“One possible approach could be offering a couple of different mixes, one for the general public and one specifically catering to individuals with moderate hearing loss,” suggested Siedenburg. “Certain adjustments to the mix might better meet the needs of this group.”
