Mobile PA -- Battery/Inverter Recommendations

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Hello,
I'd like to be able to run my sound system off of a battery and inverter for mobile performances (eg, performing at desert festivals, busking, etc). Power requirements are for a Mackie DL1608 mixer and a Mackie SRM450 powered monitor speaker. I really don't understand the power logistics very well (amps, watts, volts, etc) and am overwhelmed after google searching the topic. Where would I even go to be able to try out a battery/inverter combo with my audio gear before buying? Are there battery/inverter combos specifically for portable PAs? I'm not looking for something like a Crate Taxicab, which I own, but specifically how to power the Mackie mixer and powered monitor.

Specs for the mixer and powered monitor:
http://www.mackie.com/pdf/srm450_ss.pdf
http://www.mackie.com/products/dlseries/downloads/manuals/DL1608_SS.pdf

From these two spec sheets I see that the max power consumption for the powered monitor is 320w and for the mixer it is 48w.
A minimum of four hours battery life would be nice. And I would need to push a lot of bass.

Thanks for any input, pointing me to specific brands, websites, etc. A battery/inverter combo is the minimum, but if I could also be recharging the set-up with a solar panel or two, even better:)
 
You just want to get a 1000W switch-mode inverter. Mains is pretty much mains, dude. If you generate horrible, horrible mains, then it could influence the sound or kill something, but most battery inverters are cleaner than what comes out of your wall.

To get extended life out of your system, you may need to get a lorry battery (100Ah) or two. Or three. Just parallel them up, or make a switching box which cycles to the next battery when the voltage drops below 10.5V. One can calculate power drains etc, but I've found that the results can be very different in practise, partly because of the fine-grained nature of predicting what current such a system will draw, and partly because manufacturers' specs can be pretty far out.

These sorts of thing. http://www.ebay.com/itm/1000W-12V-D...34?pt=US_Power_Inverters_&hash=item2a2d9e6a9e
 
Thanks, bishopdante. Looking at that inverter on ebay causes me to wonder about the waveform. One thing I came across said that a square wave inverter would tend to cause hum in a sound system. Should I be looking for a pure sine wave inverter? Also, the ebay ad says the inverter can't power true sine wave equipment (printer, drill, etc). Would this apply to the mixer and monitor?
I do have a 1,500 watt inverter in my RV. It squeals (low battery alarm) when battery goes below 10.2v. I mainly use it to power a coffee maker, which almost always makes it squeal if I haven't recently driven a lot of miles to charge the battery. The inverter is connected to a deep cycle battery which seems to have plenty of life (since it can power interior lights and a vent fan for many, many hours). So, when you said a 1,000w inverter would do the job with my sound set-up, I was kind of surprised. If running a coffeemaker with a 1,500w inverter on what seems like a good battery causes the inverter to squeal, I can't imagine running a sound system off of something like that. But maybe it is the battery. Sorry, I am not well-versed in these things.
 
Perhaps you might look to 12V "native" amps and such as much as possible - it''ll reduce the amount of loss involved in power conversion. Try Parts Express for a their selection of Class D amps. If you're not needing both channels for stereo, maybe you can use a dual voice coil speaker and power one coil off each channel.

For example, I'm about to start a thread about "how to build a super-portable PA" for a local school's drama department, and basic planning so far has me working with a couple Sure stereo amp boards, a Rolls source and a small AGM battery to power it all. It will also have a wall plug for times when 120V is available.

I just have to meet with the drama teacher and find out the range of venue sizes - I'm used to making noise for rooms up to 20x30, and I'd hate to get it wrong on the PTA's dime. :-(

Best of luck with your rig!
 
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