I recently did a shoot where I had two boom ops, one with a Sennheiser ME-66, the other with a Sennheiser ME-67 (shorter). These ran via log XLR cables to an old but relatively reliable SignVideo ENG44 mixer. The mixer output to a Tascam DR-60D digital recorder. The ENG44 took 6 AA batteries and the Tascam took 4 AA's to power. I supplied phantom power to the booms from the mixer. All batteries were standard Duracell Alkaline batteries.
The Tascam ran down in about 40 minutes and had to be changed. The ENG44 ran down as well, but it took about 90 minutes. This was an all day shoot. I ran through 30 AA batteries, plus a final set of 10, about $40.00 worth. I thought.... there HAS TO BE A BETTER WAY!
I came across a couple of videos where this gent was powering his Canon T2i with an Anker battery intended to recharge iPads and cellphones. This battery had an auxiliary port capable of 12V or 9V output as well as 3 USB ports. (This is it here: Amazon.com: Anker® 2nd Gen Astro Pro2 20000mAh 4-Port Aluminum Portable External Battery Charger with 9V/12V Multi-Voltage Port and PowerIQTM Technology for iPad Air mini, iPhone 5s 5c 5; Galaxy S5 S4, Tab 2, Note, Nexus, MOTO X, G, LG Optimus, HTC O (http://www.amazon.com/20000mAh-Aluminum-Multi-Voltage-PowerIQTM-Technology/dp/B005NGLTZQ/ref=sr_1_1?s=wireless&ie=UTF8&qid=1401894629&sr=1-1&keywords=anker+20000)). So I bought one.
I charged the Anker to 100% and set up my test. I set the Aux port to 9V. (The ENG44 could take external power from 9V-18V) The Tascam can take external power via its mini-USB port. I connected the 9V to the ENG44 and the Tascam via USB. I connected the two boom mics with supplied phantom power from the mixer as before, turned everything on, pressed record and walked away.
It's a long-a** test so I went to watch a movie. (Two actually... Cloudy with a Chance of Meatballs and its sequel with my grandson!)
About 4.5 hours later, everything was still running and recording fine! The battery has an LCD readout that stated it was at 75% of full charge. If I could extrapolate a bit, then I could get a full 8 hours of continuous non-stop recording with this setup and only use about 50% of the battery's capacity!
The battery itself weighs about 1 lb., is thin and about the size of a 7" tablet. It easily slides into the mixer bag without adding much bulk at all. It cost me $79.99, so it should pay for itself by the third shoot day! It's a nontraditional way of doing things, but it works and works well for me.

My next issue will be to figure out the best way to power my wireless lavs!

I use a Remote Audio distro box with NP1's to power my mixer, recorder, 3 Lectro receivers and a IFB transmitter. My Sennheiser G2/3s run for at least 10 hours on rechargeable AA's so external pwr. really isn't needed for them.. (and the G series external power adapter is rather expensive). When I use the Lectros in a stand alone configuration, I use the eBay 12V 6.8Ah LiPo which will run them all day.

All good info, but………………….

Be aware that in certain situations, the power supply section of one piece of gear will feed noise back down the DC distribution and into other devices that are also connected to the common DC source.

Regards,

Ty Ford

Hi Bob,

I've done similar, bought a Monoprice 5000mAh battery pack for phones and use it to power my GoPro for long periods. No bigger than an Android phone and cost $29.00, has two USB outputs.

Thanks

I use a Remote Audio distro box with NP1's to power my mixer, recorder, 3 Lectro receivers and a IFB transmitter. My Sennheiser G2/3s run for at least 10 hours on rechargeable AA's so external pwr. really isn't needed for them.. (and the G series external power adapter is rather expensive). When I use the Lectros in a stand alone configuration, I use the eBay 12V 6.8Ah LiPo which will run them all day.

Rick, how long does the NP1 last when powering your setup? I do like the fact that you can just swap out one battery when needed rather than a series of bateries.

All good info, but………………….

Be aware that in certain situations, the power supply section of one piece of gear will feed noise back down the DC distribution and into other devices that are also connected to the common DC source.

Regards,

Ty Ford

Thanks, Ty. I'll keep that in mind and look for that.

Rick, how long does the NP1 last when powering your setup? I do like the fact that you can just swap out one battery when needed rather than a series of batteries.
A lot of variables Bob, so YMMV. I have two 70Wh Swit NP1 Li-on batteries and swap them at lunch time. They will usually run the gear all day (12-16 hours) 302/744, two 211s & one 411. I do film shoots so the recorder is not constantly running and I shut down receivers that are not being used in a scene. I have coax to Hirose adapters so I can power the rig with the cheap 12V LiPo batt.s if need be.

Since many of my new devices can run or charge from USB power, I've been keeping my eye on USB battery packs.

I finally found one of a size and low enough price to buy for testing.

It's a Polaroid-branded device rated at 6000mAh for $15 at a local Big Lots. The packages had actual distribution-type Big Lots price stickers rather than just ones applied at the store by employees, so it may be more widely available than some items at this chain. The packaging had 2014 copyright dates, but I didn't see any actual date code on the product.

It comes with an 8-inch Micro-USB charging cable. It's about 3"x3"x.75". It has 4 internal charge level indicator lights and two USB charging jacks. One jack is rated 1A and the other at 2A. You can use both output jacks simultaneously. It also has 2x5mm white LED lights as a crude flashlight. The On/Off switch is a small flush-mount button on the side.

Mine had 75% power left when I bought it and I'm charging it up now using a 1A USB charger. The Polaroid device is rated to charge up at only 800mA, so I imagine it could be slow going if it gets run down too low.

I had to sort through neon pink, bright green and brilliant purple to find a professional BLACK one, but I imagine having different colors could be useful for keeping mulitiple units separated or as an anti-theft protection due to the crazy colors.

I'll report back on how this one works or if I'm able to detect any noise sneaking in from using the power supply while running audio devices.