Centre for Digital Music

How to contact us
About the Department
Academic Staff
Support Staff
Research Staff
Research Students
Queen Mary Information
Contact details
Staff directory
Mile End campus
Disability & accessibility

Enrique Perez Gonzalez

Contact Details

Title: Research Student
Tel: Internal: [13] 7986
National: 020 7882 7986
International: +44 20 7882 7986
National: 020 7882 7997
International: +44 20 7882 7997
Room: Eng. 109

Research Group: Centre for Digital Music

Supervisor: Joshua Reiss

Research Topic: Automatic mixing tools for audio and music production

The Automatic Mixing Tools project aims to implement several independent systems that when combined together can generate an automatic sound mix out of an unknown set of multi-channel inputs. The research explores the possibility of reproducing the mixing decisions of a skilled audio engineer with minimal or no human interaction. The research is restricted to non-time varying mixes for large room acoustics. This research has application to live sound music concerts, remote mixing, recording and postproduction as well as live mixing for interactive scenes.

The automatic mixer research distinguishes the engineering mixing from the subjective mixing. Therefore the current research is focused on a constrained rule mixing layer and a subjective mixing layer. The rule-based section is based on engineering constraints while the subjective layer is based on a target mixing style. This target style can be extracted from previously mixed songs based on feature extraction. Two approaches are under study. One is a modified automatic mixer, whose settings can be adapted based on target features and the other is based on a multilayer feedback network. The target mixing methods rely on output feature similarity to the reference features of the target mix. It is the current belief of the author that the use of expert training data can be used to increase the convergence rate of the system.

Currently automated mixers are capable of saving a timeline of static mix scenes, which can be loaded for later use. But they lack the ability to adapt to a different room or to a different set of inputs. In other words, they lack the ability to automatically taking mixing decisions. In the current research approach the starting point is a target mixing style, rather than a fixed prerecorded setup. This has the advantage of being able to blend a mixing style of a completely different song into an unknown set of inputs.

The justification of this research is the need of non-expert audio operators and musicians to be able to achieve a quality mix with minimal effort. Currently mixing is a task which requires grate skills, practice and can be sometime tedious. For the professional mixing engineer this kind of tool will reduce sound check time and will prove useful in multiple music group and festivals where changing from one group to another should be done really quickly. Currently large audio productions tend to have hundreds of channels, being able to group some of those channels into an automatic mode will ease the mixing task to the audio engineer. There is also the possibility of applying this technology to remote mixing applications where latency is too large to be able to interact with all aspects of the mix

This research is pursuing the knowledge required to develop automatic mixtures comparable in quality to those performed by professional human mixing console operators. Implementation, subjective comparison and error distance measure between a target mixture style and the automatic mixture will measure the success of the results. By style we refer not only to a certain genre of music but also to a producer or engineer subjective contribution to a mix.


E. Perez_Gonzalez and J. Reiss, "An automatic gain normalisation technique with applications to audio mixing", To appear in Proceedings of the Audio Engineering Society 124th Convention Amsterdam, The Netherlands, 2008.

E. Perez_Gonzalez and J. Reiss, "Automatic mixing: live downmixing stereo panner", In Proceedings of DAFx-07, Bordeaux, France, 2007.

E. Perez_Gonzalez, J. Wells, and J. Reiss, "The phase amplitude controlled bit stream adder", In Proceedings of the AES 31st International Conference, London, UK, 2007.

E. Perez_Gonzalez and J. Reiss, "Idle tone behaviour in Sigma Delta Modulation", In Proceedings of the Audio Engineering Society 122nd Convention Vienna, Austria, 2007.