First, let me thank everyone who posts on Taperssection and other gear-related sites. Your contributions have been really valuable and are appreciated.
Second, after reading as much as I could, I decided on the TalentCell Rechargeable 72W 132WH 12V/11000mAh from Amazon for $65. The Amazon page actually has two options – the other is for the 8300 mAhr version for $49.
http://www.amazon.com/gp/product/B01337QXMA/Just got it a few days ago and I'm really happy with it so far... I plan to take it to the Okeechobee Music Festival next week to give it a real test.
Here are my thoughts so far:
PHYSICAL
Length: 138 mm, ~5.5 inches (including switch), Width: 80 mm, ~3.125 inches, Height 30 mm, ~1.5 inches. It will actually fit in the pocket of the CS-DR680 case. (I wouldn’t leave it in there for long periods due to the risk of flipping the switch on accidently and not realizing it.)
Manual says it weighs 500 grams.
CONNECTIONS
To connect it to the DR-680 MKII, a couple of adapter cords are needed. The power jack on the DR-680 MKII takes a 4.75 x 1.7 mm male plug. (The original DR-680 has a 5.5 x 2.1 jack). The 12 volt output port on the TalentCell battery is a 5.5 x 2.1. So, to get from the battery to the DR-680, I bought the following:
1) Male to male 5.5 x 2.1 to come out of the 12V port, about 2 feet. (If you have the original DR-680, this is all you need.)
www.amazon.com/Valley-2-1mm-5-5mm-Power-Adapter/dp/B00DX6ZUBM2) 5.5 x 2.1 Female to 4.75 x 1.7 male, about 6 inches long. (The one in the link is described as “4.8 mm” but it works.)
http://www.amazon.com/Super-Power-Supply%C2%AE-5-5x2-1mm-4-8x1-7mm/dp/B00EA4Q60KThere’s also a 9V port on the front panel, but this one is 5.5 x 2.5 and won’t fit the cables you’ll be using. (I’ve read that some people run their DR-680 at 9 volts, but let’s not go there…)
There’s also a 5 V USB port for charging your phone, etc. All the ports can be used simultaneously.
CHARGING
The TalentCell comes with a 1.5 amp charger – so to charge a completely dead battery will take about 7 hours (according to math and the instructions).
There are 5 LEDs on the battery – red shows that it’s turned on, and a set of 4 to show relative charge. There’s also an LED on the charger that shows red while charging, and turning to green when the battery is 100% charged. The switch on the TalentCell must be turned on in order to charge it (according to the instructions).
There’s a “Y” cable included so that you could charge the battery and run the DR-680 simultaneously.
In the festival wilderness, I plan to charge the TalentCell from the 120 VAC output on my old Duracell/Xantrex Powerpack 600HD. The inverter delivers a “simulated” sine wave output that doesn’t work well with some chargers. But, the Powerpack topped off the TalentCell battery without any apparent problems.
OPERATION
There’s a rocker switch to turn the battery on and off. A little too easy to accidently turn it off, but the DR-680 seems OK with that, as long as there are a set of AA batteries in the recorder. If the lights on the battery go off, it’s been accidently turned off…
The 12 V jack can apparently deliver 6 amps of power – plenty for the DR-680, which draws under an amp. I’ve read that the DR-680 draws either 8 or 9 watts with all channels and the phantom power on, so this works out to a maximum of 0.75 amps.
Total running time of the DR-680 with the TalentCell 11 Ahr battery calculates to 14.7 hours (your experience may differ…) Add another 3 hours if you want to burn through the AA batteries too.
There’s also a momentary contact button on the face that briefly lights up the LEDs to indicate the charge level.
PERFORMANCE with the DR-680
I charged the battery for a couple of hours until it was green-lighted on the charger, and then plugged it into the DR-680. Seemed to work fine!
I plugged in a pair of microphones and turned the gain up fairly high to see if the battery caused any hum or noise when close to the recorder (above, below, etc.) I didn’t hear anything unusual on the recording. Killing and restarting the TalentCell battery while recording showed the expected changeover to the DR-680 AA batteries. There was a faint “thump” for both events in the audio recording, but I doubt that anyone would notice it in a real recording.
FAA RESTRICTIONS
According to 49CFR175.10(a)(18), the TalentCell 11 Ahr (132 Wh) battery will need airline approval to fly. The smaller 8.3 Ahr (100 Wh) battery is good to go in your carry-on luggage. Lithium batteries must NEVER go in checked baggage.
“(ii) For a lithium ion battery, the Watt-hour rating must not exceed 100 Wh. With the approval of the operator, portable electronic devices may contain lithium ion batteries exceeding 100 Wh, but not exceeding 160 Wh and no more than two individually protected lithium ion batteries each exceeding 100 Wh, but not exceeding 160 Wh, may be carried per person as spare batteries in carry-on baggage.”