default_mobilelogo

Contemporary Trends in 5.1 Music Mixing

Michael Worthington

University of the Southern Cross


The analysis of mixing and re-mixing music into 5.1 surround sound is a relatively new field of contemporary music research. There have been myriad research topics explored on the many aspects of multi-channel sound ranging from in-depth technical delivery methods and monitoring to the psychology of psychoacoustic coherency of surround design.

Today’s paper aims to illustrate different mixing approaches of 5.1 contemporary music productions.
The information I’m sharing is drawn from my 2004 honours project, which investigated alternative approaches to remixing music in 5.1.
I’m currently extending that research for my PhD.

I will be presenting samples of popular 5.1 re-releases that demonstrate common practices and techniques in track panning and placement, to illustrate aspects of imaging in the mix.
I will also offer some aesthetic examples of alternative approaches to the dominant mixing paradigm.

Due to time constrictions I need to assume most of you have some basic understanding of 5.1. For those without this understanding I hope the music examples I play will make things reasonably clear. I am also providing a handout (appendix) with some more technical background for you to consult as a follow up if interested.
 

DVD-A & SACD Samples

The DVD-A and SACD releases I have sampled, demonstrate different results in the presentation of the song in the surround environment. These were chosen because the original stereo releases achieved mainstream success and the multi-channel re-released versions have received high approval ratings by reviews from web sites, audio and music magazines.

First I’ll outline a simple mixing process and common approach to re-producing a popular music release in discrete 5.1.
•    A stereo mix is initially performed and assigned to the front left and right speakers.
•    This is usually the foundation for a surround mix.
•    Individual tracks are chosen and re-assigned into the centre, surround and LFE channels.  
•    Traditional stereo engineering techniques are still employed along with any surround tools such as 5.1 panning and effects.
This basic process generates a projection a stereo image across the front speakers and second stereo image across the rear speakers. The intention is to blend the two mixes creating a three dimensional image at the centre.
Such a mix will still usually contain the main and the majority of the instruments in the front left and right speakers.
This is a fast and technically safe method of mixing making it cost effective and therefore accessible.

 
Some observations of placement common in discrete mixing:
•    Lead vocals and main accompaniments are heavily placed in the front left and right speakers, often relying on a phantom image for localisation and the main focus of the mix.
•    The Centre speaker is the least channel utilised, often displaying a soft dry mix of lead vocal bass and drums.
•    Any additional signal sent to the centre which is already present in the left & right reinforces the phantom image localisation..
•    Percussive, supporting and orchestral instruments are frequently placed in the rear channels along with embellishments and effects.

For my first example I have chosen two albums to display different results of discrete placement.
Steely Dan’s DVD-A “Everything Must Go” (mixed by Elliot Scheiner) is typical in its result of discrete mixing;
1.    The first example has a loud stereo phantom image across the front left and right containing the majority of the band, Vocals, Bass, Drums, Guitar and Piano.
2.    A stereo mix of keys, horn section, percussion and effects appearing only in the rear speakers.
3.    The vocals, bass and drums appearing in the centre channel, and there is very little sonic movement.
Play
4.    The second track is has backing vocals filling out the surround speakers; also in the rear are subtle delays of instruments and vocals sourced from the front.

Play

Certain styles of music are more suited to discrete 5.1 than others.  
More attention is required in mixing smaller ensembles than a production with many layers of instruments.
Observations In discrete mixes have shown that multiple layers of guitars or vocals easily blend the song together. While if the instrumentation is minimal, the mix is appears to have limited options.

Queens ‘Bohemian Rhapsody’ (mixed by Elliot Scheiner) with its multiple vocal tracks is a good example of extreme discrete placement with minimal spatialisation effects. Piano is in the rear and drums up front.

Play

The advantage of discrete surround mixing is specific localisation through source sound placement and 360° spatial effects; to enable the listener to pinpoint a sound to the same location from any position within the circle.
Music Engineers have adopted this basic concept from sound design for film. The idea being the entire audience localises to the same position in reference to the screen and for real world simulation.
Is precise localisation absolutely necessary for music in 5.1?
5.1 for music is either used as a simulator of a real world event or the as a creative platform to elevate it.
Often engineers claim to perform the latter but seem to utilise the former methodology.

The Sweet Spot.

The Sweet Spot in 5.1 is located at the very centre of the circle of speakers with an equal radial distance to all 5 speakers. While the sweet spot is a broader space in 5.1 than in stereo, discrete mixing in 5.1 can result in relying on the sweet spot to fully appreciate the art of the mix.
Domestic entertainment industry often recommends main seating area situated closest to the rear speakers as a workable set-up for watching DVD movies, in most cases this is due to the size of the room.
This is problematic in music appreciation, as in a position close to the rear speakers, the listener may experience for the most part reverb, embellishments, backing vocals/instruments and especially a separation of lead vocals and effects.

This one-sidedness is avoided in modern stereo mixing as the basic balance of tracks and blend of the effects all come from the same two speakers relying on the phantom image. Closer proximity to one speaker doesn’t completely spoil the blend between vocal and reverb or balance between guitar and vocals, as it is safe to say an engineer wouldn’t as pan a lead vocal to the left and its reverb to the right.

In discrete 5.1, it is a common practice to have vocal effects (delays and reverbs) often placed in the rear speakers. Effects rarely appear in the same channel as the source direct or dry signal. If the instrument/vocal is placed in the front, its accompanying effect is placed in the rear and vis versa.

Is it necessary for engineers to mix effects split from the direct source?

I believe it should be possible for the listener to be able to listen from anywhere inside or out the surround circle without missing a blend of instrumentation and production necessary for the composition and arrangement as the artists originally intended.

All productions will have a sweet spot, but does this need to be the only position from which to appreciate the music?

Examples of vocal blends dependent on sweet spot monitoring.

As I mentioned vocal delays and reverbs are often placed in the rear speakers. It is this practice of tracks & effects in opposing speakers that is a contributing factor resulting in a narrow sweet spot.
While mixing, it is common for the engineer will move outside the sweet spot just to reference what is happening elsewhere.
For the following examples I monitored outside of the centre and periodically checked the sweet spot.

This sample of Fleetwood Mac’s Rumours (mixed by Ken Caillat) is discrete while using effects to blend the instruments and vocals across the speakers. This is a technique I generally favour in my own mixes, however, it can create issues with the balance of the lead vocals as they can appear distant and low in the mix compared to the presence of the instrumentation.  
Play

Roxy Music’s ‘Avalon’ (mixed by Rhett Davies & Bob Clearmountain) discrete mix placement has all lead vocals dry strongly placed up the front, all the vocal effects in the rear only along with supporting and solo instruments,
Play

R.E.M’s ‘Drive’ (mix by Elliot Scheiner) has the lead vocal placed in the centre with vocal delays in the rear. The additional guitars and strings placed in the rear are an example of discrete placement used as an effect.
Play
In my opinion this style of mixing appears as a good presentation of the recorded sounds and production rather than a mix complementing the composition.

Example of unusual choice in placement.

Neil Young’s    album “Harvest” (mixed by Elliot Mazer) for the most part has a mix of drums placed in the left front and left rear, which is to say the least unusual. What seems to be a complete mono dry mix of the ensemble is placed centre. With stereo vocal effects left and right front. adding the mixture of dry and wet tracks between front and rear leaves the 5.1 image lob sided at times and difficult to grasp a balance point.
 
Questions raised;
•    Is precise localisation absolutely necessary for music?
•    Is it necessary for engineers to mix effects separated from their direct source?
•    Does the sweet spot need to be the only position from which to appreciate the music?



Alternatives

Bjork’s ‘Vespertine’ mix works.
The multiple layers of ambient textures and embellishments are utilised in surround creatively while they maintain a good blend within the main sections of the song.
The simple placement of the lead vocals drives the song.
There are two different stereo blends of dry vocals, delays and reverbs, which are placed in the front and rear stereo, while in the centre speaker the Vocal is dry and strong,
This allows the vocal to retain a strong presence over a large percentage of the listening circle.
This use of placement expresses the composition negating the need to find a listening position

The following are some examples of my experiments in my honours research.

A panning technique using stereo tracks has an interesting effect that seems to decentralise the sweet spot.
Experimenting with the front to rear diagonal axis as an optional placement for stereo-recorded instruments combined with subtle changes in divergence, repositions the phantom image to a location unachievable by means of standard surround amplitude panning.
This offcourse may create phase issues, but I’ve found the effect outweighs any phase incoherencies.

Silverbird by Christian Pyle utilises the stereo diagonal theory with layers of vocals and instruments for a mix required to remain more spacious and less discrete.  

This also works on minimal instrumentation such as;
Koto Music II by Peter Sculthorpe, interpreted and performed by Michael Hannan.
This recording of a grand piano interior was constructed through a series of canonical stereo loops of the plucked melody. The placements of the different parts of the ostinato seem to play off each other across the two diagonal images. This creates the illusion of movement between the different speakers. I added a little reverb over all the parts to create a subtle layer of depth.
Play
 
I use resonance and motion or a combination of both as sonic tools to create the sense of enveloping the listener.
Resonance used as a texture created from an instrument combined with stereo spatialisation techniques can give the most minimalist instrumentation its own bed of sound to envelop the listener.
Gravity by Amphibian.

Play

Motion of any type of sound can become a texture besides standard pad type sounds.
This textural motion can create a bed that gives ease to the placement of discrete sounds.
This is ideal as a 5.1 image for percussive and conventional instruments use as a carrier.
These are some examples of motion, incorporating the diagonal panning and resonance approaches.

Play.
Onsen, DB, fading light.

In an attempt to give excitement new delivery system of music appreciation, most 5.1 engineers use either discrete placement for stimulation of the listener’s sense of localisation, and/or employ time modifiers effects for spatialisation enhancement.
I’ve found the basic use of these methods does more for the technical production of the product and hype for technology than it does for the song.
There is a need for more creative input into the 5.1 mix to allow the song to exist other than just in a redesigned glorified stereo.
My ethos in mixing be it mono or 10.2 is to only exploit the technology if the I feel it complements or enhances the composition, promote the song and allow technology to feature the music and not production techniques of the genre.
 

Appendix 1

5.1 Codecs & Formats

1999-2000 saw the release of the Super Audio Compact Disc (SACD) and the Digital Versatile Disc Audio (DVD-A) as a promotion for high-resolution audio to replace the now 20-year-old CD. These formats allowed music to be marketed in 5.1 along side the stereo mix in the same package. The remixing and re-releasing of music into a 5.1 product became a large push in the music industry to promote 5.1 as an introduction to consumers as a new method in music appreciation.

These formats provide the opportunity for music to be mixed in 5.1 without the need for data reduction methods such as Dolby Digital and DTS (Digital Theatre Systems).
DVD-A uses the codec MLP (Meridian Lossless Packaging) for.
SACD uses Sony’s own for proprietary codec DSD (Direct Stream Digital).

Most DVD-As are comprised of two separate stereo formats and three different 5.1 formats. This is so the disc can play on either a standard DVD player or the new DVD-A player, but not a CD player. The stereo mixes are in Dolby Stereo 48KHz/24bit and the new Advanced Resolution format otherwise known as High Definition playable, are encoded with MLP at either 96KHz/24bit or 192KHz/24bit.
The three surround formats are available in; Dolby Digital 5.1 (DD) 48KHz/24bit, DTS 5.1 48KHz/24bit or the MLP 5.1 format encoded at 96KHz/24bit.

The SACD multi-channel mix can only be played on a SACD player although the standard stereo mix can be accessed on any CD player.
The SACD uses DSD (Digital Stream Direct). This is a completely different technology to PCM (Pulse Code Modulation), the industry standard method of audio digitisation.
DSD has a sample rate of 2.6 MHz at 1 bit.
However, SACD doesn’t play on standard DVD or DVD-A players, only on CD, SACD or hybrid DVDA/SACD players.

 

Appendix 2

5.1 Speaker layout

5 speakers plus the .1 which refers to the LFE (low frequency effects) or Sub.
 
Figure 1 (Lund 2001)
This research was performed using the ITU-R BS 775 (International Telecommunications Union) recommendation for 5.1 speaker placement. The speakers are positioned around a central listening position. The front left and right speakers are placed 30 degrees off the centre axis either side of the centre speaker. The rear left and right speakers are 110 degrees either side from the same position. The (.1) sub woofer speaker is placed in a position that is determined by the calibration of the system.
Positioning and simple calibration can be performed as follows:
1.    First the sub should be placed in the centre of the room with pink noise played through it loud enough to excite the room.
2.    The sub-speaker should then be placed the most resonant position in the room.
3.    All readings are now taken from the centre listening position in SPL, C weighting on slow response.
4.    Once the sub is in position the LFE channel is calibrated with pink noise at 89Db.
5.    The Bass management should be calibrated at 79Db. This is measured with no LFE and the main speakers turned down, the signal is sent to one of the main 5 speakers (through the sub) with the bass management engaged. The reading is then taken from the remaining crossed over frequencies emanating from the sub woofer speaker.
6.    The five main speakers are then calibrated to 85Db.

Appendix 3

The variables and manipulated parameters that influence the design of a stereo image such as stereo or mono source tracks, volume, filtering and dynamics and the effects employed, are basically the same when mixing a surround image.
For 5.1 there are some extra considerations such as LFE, bass management, delivery format and largely, the assignment of the individual tracks and their added effects to the various speakers.
Basic surround placement parameters, for redirecting a signal in 5.1;
1.    Assigning to discrete speakers, buss switching or pan control.
2.    5.1 panning into, between or across any of the speakers
3.    Centre percentage, the ability to pan to front left and right while adjusting the percentage of how much is routed into the centre speaker, this allows adjust how much a phantom image is created.
4.    Divergence is a control that adjusts the width of the panning area. A signal remains assigned to a discrete speaker while the divergence control can bleed the signal into an adjacent channel without panning or assigning it there. Combined with panning and effects, this is parameter can create localisations in which panning or assignment can’t.
ImageImage 

Figure 2 (Pro Tools reference guide)

Appendix 4

A Brief History of the developments of Surround.

•    1933 Stokowski and Bell Laboratories demonstrated a transmission across telephone lines of a live performance of the Philadelphia Symphony Orchestra. This transmission was from the Academy of Music in Philadelphia to a live audience in Washington DC’s Constitution Hall. The signal was a three-channel mix (left, right and centre speakers) with additional speakers placed around the perimeter of the hall that projected sound inwards and emitted a combination of the front three channels.

The film industry saw the value of multi-channel formats and the creative possibilities within sound design. Some of the major mainstream events that lead to the current adoption of surround sound within the music industry are:
•    1940 Fantasound, the first surround sound format. Stokowski and Walt Disney collaborated on the design and production of Fantasia. This was the first film to be released with a soundtrack prepared for multi-channel playback.
o    Fantasound innovative developments for recording and mixing;
•    Click Track,
•    Panoramic Potentiometer (Pan Pot),
•    Overdubbing,
•    Simultaneous multi-track recording,
•    1952 This is Cinerama debuts, with seven-channel surround sound
•    1953 The Robe debuts in Cinemascope, with four-channel sound.
•    1978 Superman is a landmark in surround sound.
•    In 1990, Kodak introduced Cinema Digital Sound (CDS) with the premiere of Dick Tracy. CDS was a 5.1 system. Unlike its successors CDS had no analogue soundtrack backup in case of a system crash. It failed in several screenings which led to its demise.
•    In1992 Dolby Labs released DD (Dolby Digital) with the movie Batman Returns. DD is a 5.1 format and has been chosen as the prominent audio standard for DVD (Digital Versatile Disc) releases.
•    1993 marked the first rock recording mixed in Dolby Surround (Pro Logic), “Pictures at an Exhibition,” released on Emerson, Lake & Palmer CD The Return of the Manticore.
•    In 1993 Sony Dynamic Digital Sound (SDDS)was premiered with the film Last Action Hero. SDDS is unique in that it supports 7.1 sound. In has left, mid-left, centre, mid-right, right, left rear, right rear, and a low frequency effects channel. SDDS uses the ATRAC data reduction system originally developed for the Minidisk.
•    In 1993 the 5.1 codec DTS (Digital Theatre Systems) was premiered with the film Jurassic Park. It involves synchronizing a CD-ROM with the film by using a time code track between the picture and analogue soundtrack. Like DD, DTS uses the analogue soundtrack as a backup.
(http://www.mtsu.edu/~smpte/timeline.html)


Music in surround

Quadraphonic

Playback mediums included vinyl, eight track tape cassette and open reel tape. Due to the differences between the mediums incompatible methods of delivering quadraphonic arose. Vinyl utilised a matrix system of encoding the four tracks onto a stereo track then decoding on playback into the four channels. This was the most common method due to the medium’s compatibility for stereo playback. Unfortunately there was more than one codec (coder-decoder) for the encoding/decoding process: the SQ matrix system developed by CBS Laboratories in association with the Sony Corporation and the QS matrix developed by Sansui. The discrete quad system CD-4 (compatible discrete four-channel) was the method of delivering 4 separate tracks on the different mediums available including vinyl. CD-4 used a carrier frequency of around 30KHz to relay the encoded quad. (Olson, 1995)
Quadraphonic made a valiant attempt to enter the domestic market in the 1970s. One of the most well known releases during this time period was Pink Floyd’s Dark Side of the Moon.
Quadraphonic was introduced at a time when stereo had become accepted, fashionable and reasonably priced. Audio engineers in the professional realm had some reservations about quadraphonic applications, as it was not considered to be psychoacoustically correct. There are several opinions describing why Quadraphonics failed to dominate and remain in the music reproduction market. Margouleff (1997:72) offers three reasons:
One: groove geometry couldn't support four discrete channels of sound on a vinyl record. Two: the music business didn't involve the artist enough. Three: there were too many encoding schemes and no one could agree on a standard. While the various companies involved argued, the whole thing fell by the wayside.
Holman (2000:14) suggests: “The best known reasons for the failure of quad include the fact that there were three competing formats…Quad record producers had very different outlooks as to how the medium should be used”

Unfortunately format wars are inevitable with new technologies and now with the introduction of DTS96 on Dual Disc and the development Blu-Ray it seems endless.
Delivery method aside, we are now immersed in an era of high quality music reproduction that is exploring major developments in audio digital technology.
These are:
1.    Advanced Resolution Audio otherwise known as HD (High Definition) Audio.
2.    Discrete Surround mixing for music.
These two aspects have become synonymous with each other although it isn’t a necessity for one to exist without the other.
 

REFERENCE LIST

Books and journal articles


De Lancie (1998). “Producers and Engineers on Mixing for Surround”. Mix Vol. 22, No. 10, 58
Holman, T. (2000). 5.1 Surround Sound - Up and Running.
    Boston: Focal Press
Katz, B. (2002). Mastering Audio.
    Boston: Focal Press.
Margouleff, R. Biles B. La Cerra S. (1997). “Creating Surround Sound Mixes”.
EQ Vol 8 No. 10, 72

Internet References

Durani, S. (2002) Introduction to SMR home theatre.
http://www.smr-home-theatre.org/surround2002/technology/-page_06.shtml
Elen,R. (2003:2) “Bass Management: All Bass is Covered, Part 1”. Surround
Pro. http://www.surroundpro.com/2003/nov-dec/col_bass.shtml
Elen, R. (2003). “Bass Management: All Bass is Covered, Part 2”. Surround
Pro. http://www.surroundpro.com/2003/nov-dec/col_bass.shtml
Glasco, R  (2000). Ambiophonics. Web Publication
    http://www.ambiophonics.org/
Holman, T. (2003). “Bass management Confusion Reduction” Surround Pro
    http://www.surroundpro.com/2003/may-jun03/col_5point1.shtml
Jackson, B. (2003). “Adventures in Surround Mixing”, Digital Pro Sound.    http://www.digitalprosound.com/Features/2000/Aug/6Views.htm 6

Views on 5.1

Jackson, B (2003). “Surround variations”. Mix-online.    http://mixonline.com/ar/audio_surround_variations/
Lund, T (2001). “Enhanced Localization in 5.1 Production” TC Electronic A/S
Risskov, DENMARK http://www.tcelectronic.com/media/AES
Olson, D. (1995). The Audio Page.
    http://www.rdrop.com/~dano/tunes/quad.html
Wells, F. Harvey, S (2002). “Surround 2002 Conference Wrap-Up”. Surround
Pro. http://www.surroundpro.com/2003/jan-feb/feature3.shtml
il=True
White, S (2002). “ How to Positions Speakers for 5.1 Surround Sound”
http://www.kellyindustries.com/articles/51_speaker_setup_professional.html
No author. (2001). The History of Recorded Music.
    http://www.soc.duke.edu/~s142tm01/history4.html
No author (accessed 2002). Film Sound History
    http://www.mtsu.edu/~smpte/timeline.html
Sokol, M. (2001). “Mixing in the Round”, Electronic Musician.    http://emusician.com/ar/emusic_mixing_round/
 

Other internet sites accessed.

Ambiophonics             http://www.ambiophonics.org/
Audio 3D Sound    http://www.wareing.dircon.co.uk/-3daudio.htm
Audio Coding            http://faac.sourceforge.net
Audio Revolution             http://www.audiorevolution.com/
Audiophile Audition            http://www.audaud.com/
Current Film                http://www.currentfilm.com/dvdaudio/
Dolby Laboratories            http://www.dolby.com
DTS                    http://www.dtsonline.com
DTS Entertainment            http://www.dtsentertainment.com/
DTS versus Dolby            http://www.audioholics.com/DDvsDTS.htm
DVD Audio Daily            http://dvdaudiodaily.com
DVD Talk                http://www.dvdtalk.com/reviews/
Entertain Your Brain        http://www.entertainyourbrain.com/
Electroacoustic    http://www.bham.ac.uk/music/ea-studios/homepage.htm
EQ                    http://www.eqmag.com/
Extreme Tech            http://www.extremetech.com/
Film music world            http://www.filmmusicworld.com/
Five-Channel Panning    http://www.music.miami.edu/programs/mue-/Research/
High Fidelity Review         http://www.highfidelityreview.com/reviews/
Home Theatre             http://www.hometheatermag.com/
Mix Magazine            http://www.mixonline.com
Meridian-audio    http://www.meridian-audio.com-/welcome.htm
Music Tech Research         http://www.elec.york.ac.uk/mustech
New Music Revolution        http://www.newmusicrevolution.com/
One to One                http://www.oto-online.com/
RG Review                http://www.rgreview.com/artists/
SMR Forums             http://forums.smr-forums.com:8080/
Sound and Vision            http://www.soundandvisionmag.com/
Sound and vision forums    http://www.soundandvisionmag.com/cgi-bin/ultimatebb.cgi
Sound on Sound            http://www.soundonsound.com/
Surround Associates        http://www.surroundassociates.com
Surround Pro                http://www.surroundpro.com/
Surround Professional        http://www.surroundpro.com/
Surrsound discussion group    http://mail.music.vt.edu/mailman/listinfo/-sursound

 
Conference (2002) The 4th Annual International Surround Conference &
Showcase. Beverly Hills, Surround Professional


Discography

Amphibian (2002). The Lair of the Krondal Beast {CD}
    Lismore, Independent release
Bjork (2001&2006), Vespertine, {Dual Disc-CD/DVD)
    Universal Music
Crosby, Nash. (2002). Another Stoney Evening. {DVD-A}
    L.A: DTS
Compilation (2002). Brazilian Jazz. {DVD-A}
    Los Angeles: DTS
Eagles (1976&2001). Hotel California. {DVD-A}
    Beverly Hills: Warner.
ED Function. Basek (2003). Fo_sek (CD single)
    Byron Bay: Independent
Faith hill (2002). Cry. {DVD-A}
    Germany: Warner
Fleetwood Mac (1976&2001). Rumours. {DVD-A}
    Burbank: Warner.
Hannan, M (1997). Terrains. {CD}
Sydney: Tall Poppies Records.
Kiss (2003). Kiss Symphony. {DVD}
    Melbourne: BMG
Neil Young (1972&2002). Harvest. {DVD-A}
    Burbank: Warner
Owsinki, B (2002). Setting Up Your Surround Sound Studio. {DVDV}
    New York: United Entertainment
Pink Folyd (1973&2003). Dark Side of the Moon. {SACD}
    EU: EMI
Pyle, C. (2002). In Gods Car There’s no Spare Seats. {CD}
    Sydney: BMG records.
Queen (1975&2002). A Night at the Opera. {DVD-A}
    London: EMI
Roxy Music (1982&2003) Avalon, {SACD}
    New York:  EMI
REM (1992&2002). Automatic for the People. (DVD-A}
    Los Angeles: Warner
SACD Compilation (2001). Multichannel SACD Sampler. {SACD}
    Germany: Sony
Steely Dan (2003). Everything Must Go. {DVD-A}
    Germany: Warner
Walsh, R. (2002). Etiquette and Mischief. {CD}
    Sydney: Independent release