One thing you might not be considering is that a 5000 person crowd is large so ensuring that you don't have huge SPL variation over the crowd might be an even bigger issue than just ensuring you have enough output that the SPL is acceptable at the back.
At two people per square meter your 5000 person crowd is 2500 m^2. Lets say they are arranged as a 25*100m block, this means your SPL at the back of the crowd is -40dB from the front if you just have your subs ground stacked at the front of the crowd (assuming 1m distance from the front to the subs). To reduce the front to back variation we have to move the subs further back which is one of the reasons that people are suggesting flying the subs, to reduce the distance variation of the crowd. However this "wastes" SPL capability as the subs are now radiating into free space and are further from the crowd. Flying stuff is complicated though as crushing people with stacks of speakers is considered rude.
Assuming you went with something like ground stacked subs at the front of the crowd as a line source you would want to cover the width of the crowd with subs spaced no more than 1/3rd wavelength apart at the crossover. I.E 1.4m at 80Hz so you would want 36 subs. In this scenario due to the mutual coupling and the very large number of subs though I wouldn't think these subs would have to be particularly special, just 2*15/2*18 reflex cabs should be sufficient.
Power amps are not that expensive anymore for a lot of power if your willing to buy China brands:
Morin K30 Power Amplifier Class D 2 Channel 3000w Professional Audio High Power Pa Amplifiers - Buy High Power Pa Amplifiers,Class D K30 Amplifier,Digital Power Amplifier Product on Alibaba.com
Class D Digital Amplifier Manufacturer, Full Bridge Class D Amplifier
At two people per square meter your 5000 person crowd is 2500 m^2. Lets say they are arranged as a 25*100m block, this means your SPL at the back of the crowd is -40dB from the front if you just have your subs ground stacked at the front of the crowd (assuming 1m distance from the front to the subs). To reduce the front to back variation we have to move the subs further back which is one of the reasons that people are suggesting flying the subs, to reduce the distance variation of the crowd. However this "wastes" SPL capability as the subs are now radiating into free space and are further from the crowd. Flying stuff is complicated though as crushing people with stacks of speakers is considered rude.
Assuming you went with something like ground stacked subs at the front of the crowd as a line source you would want to cover the width of the crowd with subs spaced no more than 1/3rd wavelength apart at the crossover. I.E 1.4m at 80Hz so you would want 36 subs. In this scenario due to the mutual coupling and the very large number of subs though I wouldn't think these subs would have to be particularly special, just 2*15/2*18 reflex cabs should be sufficient.
Power amps are not that expensive anymore for a lot of power if your willing to buy China brands:
Morin K30 Power Amplifier Class D 2 Channel 3000w Professional Audio High Power Pa Amplifiers - Buy High Power Pa Amplifiers,Class D K30 Amplifier,Digital Power Amplifier Product on Alibaba.com
Class D Digital Amplifier Manufacturer, Full Bridge Class D Amplifier
Oh no, I'm quite sure everyone who answered initially did think you were talking about crowds under 5k pax already.
If you'd asked about 50k pax, you'd have simply been told "Call Clair" (or whoever the big boy professional production houses are in your territory) and that would have been the end of it all.
The fact that people were emphasizing all of the other things like safety, electrical power, logistics etc was an acknowledgement that it might be do-able for you, if you make the effort to get all that right as well.
The thing is once you go beyond smaller events these extra factors increase in scale & importance far more than the simple kind of "build x number of Y design" response that might suffice for a beginner looking to do smaller (ie few hundreds in audience) events.
FWIW,
David.
The plan was to check if it is viable to go the DIY loudspeaker cabs. It would be for 1000 spectators at first and eventually expanding to 5k.
I've asked the guy, specs on what thet rent for now, ill report back. They are considering acquiring the audio gear but it is not an absolute must.
We have the well known SoLotech audio guys localy here so...
I've asked the guy, specs on what thet rent for now, ill report back. They are considering acquiring the audio gear but it is not an absolute must.
We have the well known SoLotech audio guys localy here so...