I need to power 2 THAM15's (Buttinger inuke NU6000 amp) and 2 funktion one F1 tops (unsure of power consumption) and really hoping that we are in an age now where I can make a battery system instead of using a gas generator.
Am I dreaming?
Any guidance on how to calc out the PA electrical load and match that with batteries, and also the cheapest diy battery system components would be greatly appreciated!
Am I dreaming?
Any guidance on how to calc out the PA electrical load and match that with batteries, and also the cheapest diy battery system components would be greatly appreciated!
Calculate, schmalculate - what you need is a watt-hour meter. Empirically determine how much energy it takes to run your PA configuration. How long's the show expected to go - at what sound level? You could just do an AC powered show to measure this.
Then I assume it's battery capacity - efficiency of power inverter - leads to how long the show can go on before the batteries die, or more correctly, will be damaged if you drain them any further.
Structure of the batteries will effect inverter efficiency; 12V (all batteries in parallel) will be less efficient than 24V, less efficient than 48V. Of course you have to find an inverter that accepts these higher voltages; most consumer models expect a single car battery. This is where you'd start looking into the world of solar power...
From what I've read, Tesla has a box for sale right up your alley, that can scale out to mega watt-hours in capacity.
Then I assume it's battery capacity - efficiency of power inverter - leads to how long the show can go on before the batteries die, or more correctly, will be damaged if you drain them any further.
Structure of the batteries will effect inverter efficiency; 12V (all batteries in parallel) will be less efficient than 24V, less efficient than 48V. Of course you have to find an inverter that accepts these higher voltages; most consumer models expect a single car battery. This is where you'd start looking into the world of solar power...
From what I've read, Tesla has a box for sale right up your alley, that can scale out to mega watt-hours in capacity.
A portable power source has to be able to cover everything including the momentary peak demand of the audio system.. something I have learned from doing quite a few events on generators. So a good rule of thumb is to calculate the as-configured maximum power output of all amplifiers in use, add the load for all the small signal electronics and use that as the target for the size of the power source. A system can run on a smaller source but you won't be able to push it as hard, if you do either the amplifers shut down or the power source control electronics cuts off power.
Mike Sokol has done a good series of articles on PSW about this topic - they'd be a good place to start: https://www.prosoundweb.com/unplugg...ery-power-alone-can-be-useful-in-2022-beyond/
Question: how loud does it need to be?
If you're in the live sound mindset of wringing every last bit of SPL from the speakers, then you'll need big batteries and amplifiers.
If, however, you can accept running at -15dB from full power, then your power requirements drop to 1/32. I recently took delivery of a Zoudio 4-channel amp, which puts out approx 4x 40w@4ohm, depending on the power supply voltage.
Will it push my speakers to their limits? Nope! They're rated for >1KW continuous and >2KW peak.
Will it be loud enough for speeches and background music? Definitely.
Party levels? Maybe, if the speakers are efficient and expectations are sensible.
I'd also recommend a Behringer Flow 8 mixer. It runs on a 5V supply, which means a USB battery pack is an option.
Chris
If you're in the live sound mindset of wringing every last bit of SPL from the speakers, then you'll need big batteries and amplifiers.
If, however, you can accept running at -15dB from full power, then your power requirements drop to 1/32. I recently took delivery of a Zoudio 4-channel amp, which puts out approx 4x 40w@4ohm, depending on the power supply voltage.
Will it push my speakers to their limits? Nope! They're rated for >1KW continuous and >2KW peak.
Will it be loud enough for speeches and background music? Definitely.
Party levels? Maybe, if the speakers are efficient and expectations are sensible.
I'd also recommend a Behringer Flow 8 mixer. It runs on a 5V supply, which means a USB battery pack is an option.
Chris
I have a couple of those - and I like 'em. Two Lead Acids in series puts you dangerously close to the max Vcc the amp can take, before the little chip crystals inside crack. Somehow I dont see this amp in the territory of a Gas Generator power level substitute. TI does have clamp-on current boost stage for class D amplifiers - which would take it more toward arc welder power levels - but it's an uncommon bit; I believe someone here designed a board for that, but it's not something you can just order on line, say, from Zoudio.
With so many class D amp chips, one would think the clamp-on current boost as a finished, purchasable stage would be the cat's meow. TI apparently thought so, a DIYAudio participant thought so, but no Shure/Wondom where you could just grab a board off AliExpress and boost the H*** out of (I assume) any class D amp.
https://www.taramps.com.br/en/ from the reviews of other people the power ratings on these amplifiers are real unlike most of the car audio world. You will also need larger batteries, check the maximum input voltage but I belive you can use https://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery , the cheapest way to do this is to buy raw cells and a BMS and construct your own packs. I wouldn't recommend lead acid as they are very heavy and cannot be deeply discharged without damage as such the usable capacity is less than it looks like. For DSP various people have modded the DCX2496 to run on 12V or you could use something aimed at car audio.
My own efforts with this I went with a higher battery voltage but there is a lack of off the shelf electronics that can cope with this and I'm a bit stalled with other projects to make improvements:
https://forum.speakerplans.com/higher-voltage_topic105664.html
so despite the high battery voltage I'm only at ~100W per channel, however it will run all weekend continuously due to low idle power draw.
My own efforts with this I went with a higher battery voltage but there is a lack of off the shelf electronics that can cope with this and I'm a bit stalled with other projects to make improvements:
https://forum.speakerplans.com/higher-voltage_topic105664.html
so despite the high battery voltage I'm only at ~100W per channel, however it will run all weekend continuously due to low idle power draw.
EG4-LL 48V 100Ah server rack battery + EG4 3kW Off-Grid Inverter
https://signaturesolar.com/eg4-ll-lithium-battery-48v-100ahd
https://signaturesolar.com/eg4-3kw-off-grid-inverter-3000ehv-48/
Definitely not "cheap", but it would be money well spent in the long run. You would be extremely hard pressed to DIY something equivalent for less. The batteries will last for many years.
https://signaturesolar.com/eg4-ll-lithium-battery-48v-100ahd
https://signaturesolar.com/eg4-3kw-off-grid-inverter-3000ehv-48/
Definitely not "cheap", but it would be money well spent in the long run. You would be extremely hard pressed to DIY something equivalent for less. The batteries will last for many years.
Exactly.
Can it be done, yes of course.
Cheaply...likely not.
or depends on power consuption, even if low power
what is the timeline of operation. Even low power
can challenge batteries over a timeline, so depends
and is important to do real world calculations of power being used.
And with many DIY projects
the assumption is it can be done cheaper.
looking at individual parts it can actually look to be cheaper.
In the end your sorta reinventing the wheel and working out bugs.
So it becomes rather costly.
Generators are low cost solution, and we have even had new generators.
then a few clunkers for backup, few times switching to backups.
even the clunkers did rather well. Dont forget the gas can
Can it be done, yes of course.
Cheaply...likely not.
or depends on power consuption, even if low power
what is the timeline of operation. Even low power
can challenge batteries over a timeline, so depends
and is important to do real world calculations of power being used.
And with many DIY projects
the assumption is it can be done cheaper.
looking at individual parts it can actually look to be cheaper.
In the end your sorta reinventing the wheel and working out bugs.
So it becomes rather costly.
Generators are low cost solution, and we have even had new generators.
then a few clunkers for backup, few times switching to backups.
even the clunkers did rather well. Dont forget the gas can
Maybe you can hire a Ford Lightning electric truck? It has a power outlet for tools etc. with enough oomph. And a big battery....