okay to leave batteries in mics?

[Paul Bravmann]

i'm trying to keep my gl-2 set up and ready to shoot, though sometimes it sits for a week or more between sessions. i'm wondering if it's okay to leave the batteries in my AT-897 and AT-899, and leave the mics hooked up to the camera via XLR cables and beachtek. presuming the batteries don't leak, is there any potential problem with this?

thanks,
phb

[Rich Frankel]

My experience, and I don't really want to cite the science on this one, is that its always better to take the batteries out of any condenser mic, unless the manufacturer specifically recommends against it.

The reason is this, condensors, keep a charge in the diaphram as long as the mic is powered up (this is why they require phantom power) The audio signal is captured by measuring the difference in the charge, which is why they're more sensitive than dynamics, which actually produce the electrical energy through the sound vibrations and magnetic coils.

(this is all hard and fast, if I have time later I'll post a link to a site talking about the science behind microphones.)

Anyway, Like any electrical device, the longer its holding the charge, the longer its running through its usable life, like an incadescent bulb, only one not likely to blow eventually. The point is, powering the mic down when not in use is simply good practice for protecting your investment and insuring a long life of great sound for your mic. (you'll also obviously run your batteries down more quickly.)

No harm in leaving the cabling connected to the GL2.

I'm not intimately familiar with your two mics, but I'll add, if they have "off" switches on them, that would cut the circuit, and then you could leave the battery in, since it would have the same practical effect of powering down the microphone's charge.

Hope this helps.

~Rich

[Bryan Beasleigh]

If the battery was to swell and leak for any reason it would create no end of grief. I try to empty any device that might not be used for a long period of time. Notice that I said "try" Like most i've opened something left for a long perios to find a corroded mess.

[Aaron Koolen]

Remove it. I left my AA battery in my K6 capsule for about a week or so and it was not a pretty sight. During shooting I could hear all this crackling and stuff and couldn't figure it out. When I finally opened the thing up it was all green. Got it professionally cleaned and serviced and it worked like a charm again.

It's not worth the hassle especially, if like me, it starts to happen during a shoot.

Aaron

[Marty Atias]

You do not need to remove the battery unless you put it in storage for a long period of time. This is confirmed by the 899's spec sheet.

All self powered mics have either an on /off switch or are self switched when connected to an input device. The battery life in these mics is rated at 1200 hours. If there is no switch, simply unplug the mic. That is certainly simpler, faster and more fool proof than removing and replacing the battery each time you want to use it. No professional sound person I know (I'm talking broadcasters) remove the battery unless it's time to replace it with a new one.

Aaron must have had either a bad or weak battery for it to leak after a week. Of course, it helps if you turn the mic off when you're not using it.

[Paul Bravmann]

thanks for all your thoughts re: leakage, uncoupling, etc... i think i'll just try to use good batteries (coppertop alkalines, and not the toshibas my mics came with) and unplug the mics (no off switch) when not in use and hope for the best, knowing full well that i've been warned...

phb

[Aaron Koolen]

Yes, I was not trying to say that with everything working properly you shouldn't do it for a week. It's just that if for some reason it's not (My battery was new though, but maybe faulty) then you could be in trouble.

Never hurts to be safe
Aaron