Sound Talking – 3 November at the London Science Museum

On Friday 3 November 2017, Dr Brecht De Man (one of the audio engineering group researchers) and Dr Melissa Dickson are chairing an unusual and wildly interdisciplinary day of talks, tied together by the theme ‘language describing sound, and sound emulating language’.

Despite being part of the Electronic Engineering and Computer Science department, we think about and work around language quite a lot. After all, audio engineering is mostly related to transferring and manipulating (musical, informative, excessive, annoying) sound and therefore we need to understand how it is experienced and described. This is especially evident from projects such as the SAFE plugins, where we collect terms which describe a particular musical signal manipulation, to then determine their connection with the chosen process parameters and measured signal properties. So the relationship between sound and language is actually central to Brecht’s research, as well as of others here.

The aim of this event is to bring together a wide range of high-profile researchers who work on this intersection, from maximally different perspectives. They study the terminology used to discuss sound, the invention of words that capture sonic experience, and the use and manipulation of sound to emulate linguistic descriptions. Talks will address singing voice research, using sound in accessible film for hearing impaired viewers, new music production tools, auditory neuroscience, sounds in literature, the language of artistic direction, and the sounds of the insane asylum. ‘Sounds’ like a fascinating day at the Science Museum!

Register now (the modest fee just covers lunch, breaks, and wine reception) and get to see

  • Maria Chait (head of UCL Auditory Cognitive Neuroscience lab)
  • Jonathan Andrews (on soundscape of the insane asylum)
  • Melissa Dickson (historian of 19th century literature)
  • Mariana Lopez (making film more accessible through sound)
  • David Howard (the singing voice)
  • Brecht De Man (from our group, on understanding the vocabulary of mixing)
  • Mandy Parnell (award winning mastering engineer)
  • Trevor Cox (categorising quotidian sounds)

In addition, there will be a display of cool sound making objects, with a chance to make your own wax cylinder recording, and more!

The full programme including abstracts and biographies can be found on


The creation of auto-tune


From 1976 through 1989, Dr. Andy Hildebrand worked for the oil industry, interpreting seismic data. By sending sound waves into the ground, he could detect the reflections, and map potential drill sites. Dr. Hildebrand studied music composition at Rice University, and then developed audio processing tools based on his knowledge in seismic data analysis. He was a leading developer of a variety of plug-ins, including MDT (Multiband Dynamics Tool), JVP (Jupiter Voice Processor) and SST (Spectral Shaping Tool). At a dinner party, a guest challenged him to invent a tool that would help her sing in tune. Based on the phase vocoder, Hildebrand’s Antares Audio Technologies  released Auto-Tune in late 1996.

Auto-Tune was intended to correct or disguise off-key vocals. It moves the pitch of a note to the nearest true semitone (the nearest musical interval in traditional, equal temperament Western tonal music), thus allowing the vocal parts to be tuned. The original Auto-Tune had a speed parameter which could be set between 0 and 400 milliseconds, and determined how quickly the note moved to the target pitch. Engineers soon realised that by setting this ‘attack time’ very short, Auto-Tune could be used as an effect to distort vocals, and make it sound as if the voice leaps from note to note in discrete steps. It gives it an artificial, synthesiser like sound, that can be appealing or irritating depending on taste. This unusual effect was the trademark sound of Cher’s 1998 hit song, ‘Believe.’

Like many audio effects, engineers and performers found a creative use, quite different from the intended use. As Hildebrand said, “I never figured anyone in their right mind would want to do that.” Yet Auto-Tune and competing pitch correction technologies are now widely applied (in amateur and professional recordings, and across many genres) for both intended and unusual, artistic uses.


The loudness war


Dynamic range compression is used at almost every stage of the audio production chain. It is applied to minimise artifacts in recording (like variation in loudness as a vocalist moves towards or away from a microphone), to reduce masking and to bring different tracks into a comparable loudness range. Compression is also applied in mastering to make the recording sound ‘loud.’ since a loud recording will be more noticeable than a quiet one, and the listener will hear more of the full frequency range. This has resulted in a trend to more and more compression being applied, a ‘loudness war.’

Broadcasting also has its loudness wars. Dynamic range compression is applied in broadcasting to prevent drastic level changes from song to song, and to ensure compliance with standards regarding maximum broadcast levels. But competition for listeners between radio stations has resulted in a trend to very large amounts of compression being applied.

So a lot of recordings have been compressed to the point where dynamics are compromised, transients are squashed, clipping occurs and there can be significant distortion throughout. The end result is that many people think, compared to what they could have been, a lot of modern recordings sound terrible. And broadcast compression only adds to the problem.

Who is to blame? There is a belief among many that ‘loud sells records.’ This may not be true, but believing it encourages people to participate in the loudness war. And each individual may think that what they are doing is appropriate. Collectively, the musician who wants a loud recording, the record producer who wants a wall of sound, the engineers dealing with artifacts, the mastering engineers who prepare content for broadcast and the broadcasters themselves are all acting as soldiers in the loudness war.

The tide is turning

The loudness war may have reached its peak shortly after the start of the new millenium. Audiologists became concerned that the prolonged loudness of new albums might cause hearing damage. Musicians began highlighting the sound quality issue, and in 2006, Bob Dylan said, “… these modern records, they’re atrocious, they have sound all over them. There’s no definition of nothing, no vocal, no nothing, just like static. Even these songs probably sounded ten times better in the studio.” Also in 2006, a vice-president at a Sony Music subsidiary wrote an open letter decrying the loudness war, claiming that mastering engineers are being forced to make releases louder in order to get the attention of industry heads.

In 2008 Metallica released an album with tremendous compression, and hence clipping and lots of distortion. But a version without overuse of compression was included in downloadable content for a game, Guitar Hero III, and listeners all over noticed and complained about the difference. Again in 2008, Guns N’ Roses producers (including the band’s frontman Axl Rose) chose a version with minimal compression when offered three alternative mastered versions.

Recently, an annual Dynamic Range Day has been organised to raise awareness of the issue, and the nonprofit organization Turn Me Up! was created to promote recordings with more dynamic range.

The European Broadcasting Union addressed the broadcast loudness wars with EBU Recommendation R 128 and related documents that specify how loudness and loudness range can be measured in broadcast content, as well as recommending appropriate ranges for both.

Together, all these developments may go a long way to establishing a truce in the loudness war.

King Tubby – Playing the mixing desk

King Tubby (1941 –1989) was a Jamaican electronics and sound engineer, and his innovative studio work is often cited as one of the most significant steps in the evolution of a mixing engineer from a purely technical role to a very creative one.

In the 50s and 60s, he established himself as an engineer for the emerging sound system scene, and he built sound system amplifiers as well as his own radio transmitter. While producing versions of songs for local deejays, Tubby discovered that the various tracks could be radically reworked through the settings on the mixer and primitive early effects units. He turned his small recording studio into his own compositional tool.

Tubby would overdub the multitracks after passing them through his custom mixing desk, accentuating the drum and bass parts, while reducing other tracks to short snippets. He would splice sounds, shift the emphasis, and add delay-based effects until the original content could hardly be identified.

King Tubby would also rapidly manipulate a tuneable high pass filter, in order to create an impressive narrow sweep of the source until it became inaudible high frequency content. In effect, he was able to ‘play’ the mixing desk like a musical instrument, and in his creative overdubbing of vocals, became one of the founders of the ‘dub music’ genre.

See G. Milner, Perfecting Sound Forever: The Story of Recorded Music: Granta Books, 2010.

A short history of graphic and parametric equalization

Early equalizers were fixed and integrated into the circuits of audio receivers or phonograph playback systems. The advent of motion picture sound saw the emergence of variable equalization. Notably, John Volkman’s external equalizer design from the 1930s featured a set of selectable frequencies with boosts and cuts, and is sometimes considered to be the first operator-variable equalizer.
Throughout the 1950s and 1960s, equalizers grew in popularity, finding applications in sound post-production and speech enhancement. The Langevin Model EQ-251A, an early program equalizer with slide controls, was a precursor to the graphic equalizer. One slider controlled a bass shelving filter, and the other provided peaking boost/cut with four switchable center frequencies. Each filter had switchable frequencies and used a 15-position slide switch to adjust the gain. Cinema Engineering introduced the first graphic equalizer. It could adjust six bands with a boost or cut range . However, with graphic equalizers, engineers were still limited to the constraints imposed by the number and location of bands.
By 1967, Saul Walker introduced the API 550A equalizer, whose bandwidth is inherently altered relative to the amount of signal boosted. This EQ, like others of its time, featured a fixed selection of frequencies, and variable boost or cut controls at those frequencies. In 1971, Daniel Flickinger invented an important tunable equalizer. His circuit, known as `sweepable EQ’, allowed arbitrary selection of frequency and gain in three overlapping bands.
In 1966, Burgess Macneal and George Massenburg began work on a new recording console. Macneal and Massenburg, who was still a teenager, conceptualized an idea for a sweep-tunable EQ that would avoid inductors and switches. Soon after, Bob Meushaw, a friend of Massenburg, built a three-band, frequency adjustable, fixed-Q equalizer. When asked who invented the parametric equalizer, Massenburg stated “four people could possibly lay claim to the modern concept: Bob Meushaw, Burgess Macneal, Daniel Flickinger, and myself… Our (Bob’s, Burgess’ and my) sweep-tunable EQ was borne, more or less, out of an idea that Burgess and I had around 1966 or 1967 for an EQ… three controls adjusting, independently, the parameters for each of three bands for a recording console… I wrote and delivered the AES paper on Parametrics at the Los Angeles show in 1972… It’s the first mention of `Parametric’ associated with sweep-tunable EQ.”
  • Bohn, D.A. Operator adjustable equalizers: An overview. In Proc. Audio Eng. Soc. 6th Int. Conf.: Sound Reinforcement; 1988; pp. 369–381.
  • Reiss, J.D.; McPherson, A. Filter effects (Chapter 4). In Audio Effects: Theory, Implementation and Application; CRC Press: Boca Raton, FL, USA, 2015; pp. 89–124.
  • Flickinger, D. Amplifier system utilizing regenerative and degenerative feedback to shape the frequency response. U.S. Patent #3,752,928 1973.
  • Massenburg, G. Parametric equalization. In Proc. Audio Eng. Soc. 42nd Conv.; 1972.