Topic: Battery life Church CA-Ugly pre

[dbindc]

Does anyone know approximately how long a standard 9v alkaline will last in the ca-ugly powering DPA 4061's and assuming I'm using the full 20db boost?   Did one 3 hr show already.  Should I swap out the battery before I use it tonight for a 2-3 hr. event?

[fmaderjr]

You should easily be be good to go for a couple more shows. I think all the Church pres are rated for 30+ hours powering mics of average drain (though I believe the DPA's use a good bit more juice than average).

Get yourself a cheap multimeter like this:
http://www.surplusgizmos.com/Digital-Multimeter-DMM-Large-Display-and-TransistorDiode-Test_p_153-1384.html
and test the battery before each show. As long as it is putting out 8.5+ volts, you should be good for another show. This will save you a ton on batteries in the long run. No longer any need to toss them when they still have a lot of life left just to be safe.

[rastasean]

Get yourself a cheap multimeter like this:
http://www.surplusgizmos.com/Digital-Multimeter-DMM-Large-Display-and-TransistorDiode-Test_p_153-1384.html
and test the battery before each show. As long as it is putting out 8.5+ volts, you should be good for another show. This will save you a ton on batteries in the long run. No longer any need to toss them when they still have a lot of life left just to be safe.

FANTASTIC ADVICE!
I forget what the cut off is, it may be around 6 volts and if its below that, chunk it.

[fmaderjr]

I can't find the post now, but I copied a Chris Church post where he says his preamps need 7.0 volts to operate and 7.5 volts to operate optimally. He recommended 8.0 volts for safety.  I guess my original 8.5 was a bit conservative (I was writing from memory). Lordbelial has recommended at least 8.2 at start of show for safety.

[dbindc]

Thanx for all the helpful advice.  My cheapo digital multimeter says 8.97v, so I guess I'm good to go.  First time running it into my new R-09HR so I'm excited.  So long Microcrapper!

[dimm0k]

You should easily be be good to go for a couple more shows. I think all the Church pres are rated for 30+ hours powering mics of average drain (though I believe the DPA's use a good bit more juice than average).

Get yourself a cheap multimeter like this:
http://www.surplusgizmos.com/Digital-Multimeter-DMM-Large-Display-and-TransistorDiode-Test_p_153-1384.html
and test the battery before each show. As long as it is putting out 8.5+ volts, you should be good for another show. This will save you a ton on batteries in the long run. No longer any need to toss them when they still have a lot of life left just to be safe.

While I don't know much about the specifics of a battery I was thinking of getting a multimeter for the same reason you described.  The only issue I have with this is, wouldn't this only tell you that there's enough juice to give you that reading at that moment rather than how much juice is left?

[fmaderjr]

I don't know the technicalities, but from reading discussions here I understand that if the multimeter shows 8.2+ volts at the moment, there will be enough left for a show.

[sunjan]

As long as it is putting out 8.5+ volts, you should be good for another show. This will save you a ton on batteries in the long run. No longer any need to toss them when they still have a lot of life left just to be safe.

While I don't know much about the specifics of a battery I was thinking of getting a multimeter for the same reason you described.  The only issue I have with this is, wouldn't this only tell you that there's enough juice to give you that reading at that moment rather than how much juice is left?

Dimm0k, you're absolutely right. The reading won't tell you how much juice there is left.

The only way to tell is by learning your specific discharge curve for your particular rig (like gutbucket did in the thread below). This will largely depend on which brand/type of battery you're running, but also the mic model and which version of the CA pre you have. Chris Church modified the specs, so recent builds draw less current.

Once you've gotten to know the discharge curve, you can extrapolate how long you can run your rig at any given reading:
http://www.mpoweruk.com/performance.htm
http://www.batteryuniversity.com/partone-16a.htm

Gutbucket experienced distortion to his mics already by 8.5V:
http://taperssection.com/index.php/topic,91415.msg1455320.html#msg1455320

So unless you've tested and ran your mics with low voltage, Chris advise against running his gear below 8.5V.

[dimm0k]

Guess I will give the green light to purchase a multimeter.  Thanks sunjan and mshilarious!  This is invaluable info not just for this specific application, but for anything else that uses batteries.