Following are notes posted to the AF list in regards to a 60k (6x 10K mono stack) PA system designed and installed for Canaan Downs Festival 2008/9.

System Design was by Simon Kong & Matthew Ayton. Sound equipment was supplied by BounceNZ, ChCh.

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After a decade I have finally managed to work with my six channel reinforced sound concepts again.

Matthew Ayton and myself designed a six channel mono system for the main zone of the Festival that consisted of six 10K mono speaker stacks surrounding an area big enough for over a 1000 people.

The whole system was operated by standard FOH mixing desks and could be mixed in a conventional way. The individual speakers channels were accessible by the sends on each input channel allowing each input to have its own six way pan setup. The overall system was controlled by six individual masters.

One exciting aspect was being able to control the whole PA at a systems processing level (EQ's, X-over's, compressors, etc) remotely, via a wireless laptop.

We also installed our 6-way panning joy stick as an fx-send so that any channel (or groups of) could be assigned to the joystick and manually moved around the sound field.

Primarily this project was a proof of concept exercise. Not many people utilised the system or its full potential during their performance.

However Tony Sheard, live sound engineer for The Little Bushman fully exploited the 6ch potential of the system and did lots of subtle 6 way panning on drum microphones putting the audience inside the drum kit and cymbal's. He also did lots of manual joystick panning of vocals and guitars during an hour long set from the Bushman.

As an experienced live sound engineer, Tony (and the Bushman) were really impressed with the sound of the multi channel system and the way it operated. Tony could not get enough of the joystick and wanted a second one.

I was personally very pleased with the design and the results of the system as it was the culmination of many years of hard work. There was an expected issues of sound clashing around the outside the edges of the system but the sound anywhere inside the speaker stacks was phenomenal, powerful, immersive and dimensionally dynamic.

Phase cancellation between speakers stacks was completely controlled and predictable, with the design creating multiple large sweet spots and alternatives. The on-stage sound for live performers was clean and free of feedback. While there was some discernible delay from the system while on stage the "whole" sound was cohesive and in was in continuous context with itself.

Essentially when you listened to the system you heard 'one' sound, while the sound of individual speakers stacks were discernible the overwhelming experience was the sound of the system as a whole object, reflections and delays inherent in the sound appeared and remained in continuous context to the whole sound where ever you moved.

So the reflections and delays which are predictable in a surround system maintained a continues and therefore transparent relationship to the overall time alignment of the system. The system formed a three dimensional harmonic object of standing waves where even the discordant or mis aligned aspects of the object appeared as part of the whole not abstract.

If you require a visual reference of what I am describing - see symatics

http://www.youtube.com/watch?v=GCUg4Kx_CjY

As such not a single performer complained or struggled with the setup to such a point that it effected their performance. In fact quite the opposite happened and every single live band and DJ loved the result of the system and the way it presented their sound.

Audiences also thoroughly enjoyed the sound space and the complete immersion in surround sound, however some commented that the system was to loud.

Considering that this was a completely unique design never before used in a live sound capacity I was very satisfied with the clean result. More importantly for me the system worked as designed with only minor adjustment of systems processing, delays or EQ's.

This for me is proof that with a careful study of speaker design and the know reinforcement properties of speakers cabinets, designs on paper can translate perfectly into a real world production environment where %100 positive results are required for a great show where professional performers are engaged.

Suffice to say I believe that with careful and proper design and utilisation there is no reason why multi channel audio systems can not be used on a regular basis for any form of live performance.

Also that in conjunction with Leytons report the it is apparent to that multi channel systems are completely scalable from 60watts, 6K or 60K and beyond.

In regards to my own agenda to experiment with and design large scale multi channel sound reinforcement this latest project is a major personal mile stone for me.

However while the proof of concept worked with overwhelming success. What remains to be found is performers & performance that utilises multi channel systems to their full potential.

Looking forward in the system design the next step is to introduce increased layers of digital processing to allow for automated multi channel effects & panning. Further I want to start to utilise the processing abilities of Ambisonics to enhance the positioning and spatialisation of sounds across the system.

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Here is an excellent time-lapse video that shows how people interacted with the sound field. Notice the even spacing of dancers indicating the dispersion of nodal points & sweet spots.

Tom Cosm - Final Set
http://www.youtube.com/watch?v=CTQeZ8d0Dfw

Acknowledgements:

Matthew Ayton, Leyton, Andrew Mackinnon, Sage Forest & Ben Fulford for all their personal support around this project.

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If anyone would like copies of the designs I have a PDF available on request.

contact: simon.kong at gmail.com