Specifications

1. System design
Customer’s requirements
The rst step in any design is to chart the customer’s
requirements.Sometimestherequirementscanbefoundin
aformaltenderifaconsultanthasalreadybeeninvolved
in the customer’s system specication process. In many
cases the consultant or system integrator has to discuss
the customer’s requirements in depth to nd the most
appropriate system specications, and perhaps suggest
additional system possibilities made possible by new
technologiesonthemarket.
System specications
Thesecondstepistodrawupasystemspecicationbased
on the customer’s requirements. A system specication
documentcontainstherequirementsforasystemtofulll
as operational parameters. The system specications
shouldnotincludeanydirectiontoactualsolutionsasthat
wouldnarrowthescopeofpossibilitiesinthedesignstage.
Onlybykeepingthesystemspecicationsandthedesign
solutionoptionsstrictlyseparatedcanthebroadscopeof
choicesbetrulyconsideredbythedesigner,allowingfor
maximumexibility, qualityandcreativityinthe design
stage.
Design options
Basedonthesystemspecicationsdocument,basicdesign
optionscanbeconceived.Themaindecision to makeis
the selection of the technology to be used: analogue or
digital,point topoint ornetworked, closed (proprietary)
oropen(manufacturer-independent)platformsetc. These
decisionsarefundamentalastheydeterminethedegreeof
freedomallowedinfurtherdesignstages.
Selection of network and audio devices
After the technology platforms have been selected the
system’s actual network and audio devices must be
selected. Input parameters for selection include feature
set,audioquality,technicalreliability,supplierreliability,
complexityandofcoursecostlevel.Therearenoproducts
withan‘A-score’onalloftheseparameters;qualitycomes
withhighercosts,morefunctionalitycomeswithamore
complexuserinterface,etc.Thedesignermuststudyeach
systemcomponent’sfeaturesetindepthtoassessifitmeets
the system specications or not, and conceive creative
solutionsincasenomatchingproductsareavailable.
Design tools
The more complex a system the more important design
tools become. A small system can be described in words or
anexcelsheet,butlargerormorecomplexsystemshaveto
bedescribedindrawingstobeabletocommunicatethem
to all stakeholders in a project. In these cases software
programs are used to construct system designs, such as
AutoCAD in the contracting business, StarDraw in the
audio markets and CobraCAD for CobraNet™ system
designs.
System test
A very important part of the network design process
is to conduct (sub) system tests. Especially network
systemsusingmanagedswitchesofferanextremelyhigh
functionalitylevelthatrequiresystemteststoverifythat
allparametershavebeenprogrammedcorrectly.
Training & after sales
A networked audio system offers different functionality
compared to analogue systems. Therefore the design of
appropriate after sales and training activities for future
users of the system is an important part of the design
stage.