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View Full Version : Which Lasts Longer: 2 AA's or a 9-Volt?


Rejoice Music
12-02-2007, 09:40 PM
Just curious about this, from those of you with this kind of knowledge. My latest Taylor has the 9-volt (and a much easier compartment to open!).

Does this type of battery last longer than 2 AA's?

oldgeezer
12-02-2007, 11:10 PM
Since an AA is 1.5 volts(as stated on the battery I'm looking at), then two of them would equal 3 volts. That's a third less voltage or power than a 9 volt, so my guess would be that the 9 volt would last longer.

coreybox
12-03-2007, 06:28 AM
Since an AA is 1.5 volts(as stated on the battery I'm looking at), then two of them would equal 3 volts. That's a third less voltage or power than a 9 volt, so my guess would be that the 9 volt would last longer.

AA has a higher amp hours rating though (if I remember correctly).

The new system also has an LED running, which usually draws way more power than anything else.

I wouldn't be surprised if the new system has less life per battery, but I'm totally guessing.

bernaby
12-03-2007, 06:47 AM
Taylor is claiming a longer battery life fron the newer 9V ES system. At a road show which I attended the spokesperson said that battery life was almost twice that of the AA"s.

tholmes
12-03-2007, 08:51 AM
AA has a higher amp hours rating though (if I remember correctly).

The new system also has an LED running, which usually draws way more power than anything else.

I wouldn't be surprised if the new system has less life per battery, but I'm totally guessing.


Battery life is dependent on the amperage draw of the device that it's powering. FWIW, AA batteries typically have about 2850 mAh capacity whereas 9V batteries are around 625 mAh. If you know the amperage draw of the device, it's easy to figure (approximate) battery life.

note: IIRC, two AAs would have the same mAh capacity as a single battery (in typical configuration) but the nominal voltage (1.5V per battery) would be doubled.

But I might be wrong

Tom

Yoder
12-03-2007, 10:19 AM
Which lasts longer? Depends on who you ask...


http://www.maxitmag.com/images/stories/reviews/cellphones/energizer-mobile-phone.jpg

Herb Hunter
12-03-2007, 10:32 AM
Burdened by the same load, a pair of AAs cells would last longer than a 9-volt battery. I believe, though I don't really know, that the new Expression System imposes a lighter load on the 9-volt battery than the first generation ES did on the pair of AA cells it used. Because of this (if I'm right), it is likely that the 9-volt battery in the new ES lasts longer than the AAs did in the older ES.

Hapa
12-03-2007, 11:06 AM
If it helps I've used my 07 GS with the new ES at church every Sunday for 2-3 hours for the last 3 months and haven't changed the 9-volt yet...

SongwriterFan
12-03-2007, 11:06 AM
Burdened by the same load, a pair of AAs cells would last longer than a 9-volt battery.


A load of the same AMPS, yes.

But what if the load were of the same POWER, but could be run at either 3V or 9V? the 9V load would require FEWER amps. Thus, the 9V could actually run longer than the AA's (without actually doing the math to prove it).

phuufme
12-03-2007, 11:12 AM
Wow, I was scrolling down this thread hoping for an answer, but it looks like a math equation to me.:D

preston
12-03-2007, 12:02 PM
Wow, I was scrolling down this thread hoping for an answer, but it looks like a math equation to me.:D

A guy playing an 814CE with a 9 volt system leaves Chicago on a train going east at 50 mph; his friend Joe, playing a 710CE with AA batteries, leaves on a train from New York going west at 48 mph . . . . .:ha:

mdunn
12-03-2007, 12:07 PM
A guy playing an 814CE with a 9 volt system leaves Chicago on a train going east at 50 mph; his friend Joe, playing a 710CE with AA batteries, leaves on a train from New York going west at 48 mph . . . . .:ha:


They will meet for Pizza in Altoona, PA:D

Joe F
12-03-2007, 12:24 PM
If it helps I've used my 07 GS with the new ES at church every Sunday for 2-3 hours for the last 3 months and haven't changed the 9-volt yet...


Mine is also plugged in every Sunday for 3-4hrs or so between two services and rehearsals. The light was still lit (battery good) after around 6 weeks of this. I finally changed it Saturday just because I was getting a little nervous. I guess my bunny still had some drum beating left to do.

With my old 2 AA ES, I usually had to change every 4 weeks or so under the same conditions. The low battery indication on the old ES was distortion and low volume however instead of a red light going out. :D

SongwriterFan
12-03-2007, 12:28 PM
Wow, I was scrolling down this thread hoping for an answer, but it looks like a math equation to me.:D

It *is* a math equation. But the "unknown" is the amount of current the original and new ES systems draw.

Nelson
12-03-2007, 01:12 PM
If it helps I've used my 07 GS with the new ES at church every Sunday for 2-3 hours for the last 3 months and haven't changed the 9-volt yet...

I've changed the battery once since getting the retrofit in February. Nearly every Sunday in Church, coffee house gigs, Praise band rehearsals and concerts, recording. I'd have changed the AA's at least three times by now.

Michael T
12-03-2007, 08:37 PM
I too questioned battery life expectancy after watching the DVD that came with my 2007 T5C2-12. The demo mentioned 40 hours of use. With a little web crawling I came across the "power bug" lithium 9 volt ad supposedly extending the life X 4 with a much shallower power loss curve. Further research prompted me to look up the data on the ultralife page, the powerbug is the same model # (U9VL-FP) but without the music industry specific wrapper. 8 bucks at batteries plus, they also have another model that is rated as even longer but it may have slightly different dimensons. The voltage drop off graph for the difference between an alkaline and the ultralife lithium is dramatic. I don't know the drain rate for 2 1.5 batts verses a single 9 volt but there is a definate difference in consistant output and draw life between the HD Alkaline and the ultralife lithium U9VL-FP.