An investigation into the motivation behind the use of Dynamic Range Compression (DRC) in Popular Music Production
By Austin Moore, Rupert Till & Jonathan Wakefield
Dynamic range compression (DRC) is a much-used process in music production. Traditionally it was implemented to control the dynamic range of program material to minimize the risk of overloading recording devices. However, over time DRC started to be used as a creative effect in addition to its traditional role as a preventative measure. In a professional recording environment, it is common for engineers to have access to several different types of DRC unit, each with their own purportedly unique sonic signature.
This paper sets out to investigate the following:
Which are the most commonly used types of DRC in popular music production?
Which are the most common music sources to process using these DRC units?
How do music producers describe the sonic signature of DRC?
What are the most common reasons to apply DRC in productions? Is it for dynamic range control or something else?
The research used a mixed methodology of grounded theory and content analysis to extract qualitative and quantitative data from a sample of 100 interviews spanning 14 years. The data came from a series of articles by mix engineers and producers in the magazine Sound on Sound. Content analysis was used to extract data relating to the popularity of compressor types and specific DRC units. Grounded theory was utilized to generate an overarching theory that would help to explain the motivation behind the use of DRC and also to gain insight into how producers described the sonic signature of the DRC process.
This study is part of a larger research project that investigates non-linear processing in music production with a focus on DRC and the 1176 FET compressor.
Austin’s research uses the extensive archive (279 articles) of The Mix and Sound On Sound magazines’ ‘Classic Tracks’ and ‘Secrets of the Mix Engineers’ series. It’s good to see this valuable and authentic journalistic resource being used in academic research. He uses Grounded Theory and the dataset is the words that the engineers themselves used. He notes that 47% of the dataset pertains to commentary about the vocals, and talks us through the different types of audio that respondents comment on (vocals, drums, room etc).
We see a hierarchy of classic compressors, and Austin notes the dominance of the 1176 FET compressors in many sound sources and recordings.The wordcloud (see photo) is an entertaining illustration of the adjectives and verbs that engineers use to describe sound.
The second part of the research was survey-based, using a hand-picked sample of knowledgable and notable engineers. Here are some of the interesting takeaways about unit selection
- For compressing vocals, the 1176 and LA2A were equally popular
- FET and opto were the most popular styles for compressing bass
- Room mic compression showed the 1176 to be the most popular choice by a substantial margin.
- For spot drum mics engineers favoured the dbx165 and the 1176 equally
Room mics are often referenced when respondents were talking about creating a ‘vibe’ or ‘feel’, with ‘pumping’ being the most common adjective for the room sound.
Austin then goes into serious (and methodologically robust) descriptions of the kind of words that engineers use when talking about their use of compression. I hope he publishes this – it will represent a valuable and unique record of the way audio professionals have talked about some of the most successful recordings of the last 50 years.