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Question Best Practices regarding battery on a JP15

P

Pedro Malta

Member
Joined
Nov 8, 2017
Messages
5
Is it encouraged or advised against removing the battery when the guitar is not in use?

I've read in a few places people having issues with battery draining. Removing the battery should fix this, right? specially when you are out of town for longs periods of time.

What do you guys think? Should I just leave it there and make sure it is not plugged in?

Thanks,
 
I leave mine in and make sure guitar is not plugged in. I keep track and replace them about every six months as a precaution
 
Without the cord plugged in, the power is not turned on, so the battery should not be draining. The problem is that many guitar players are not used to having active guitars, so they leave them plugged in, and the battery drains. For bass players, it's something they have had to deal with for far longer.
 
I take mine out after every time I play unless I am going to be home for that time period (ie, weekends). Batteries are easily replaceable, the guitar is not. Yes this is probably excessive, but...

The only concern I have for doing this is that I am always afraid the springs that hold them in (the Majesty takes 3 AAs) are going to snap off.
 
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fjk1138 said:
I take mine out after every time I play unless I am going to be home for that time period (ie, weekends). Batteries are easily replaceable, the guitar is not. Yes this is probably excessive, but...

The only concern I have for doing this is that I am always afraid the springs that hold them in (the Majesty takes 3 AAs) are going to snap off.
Click to expand...

Surely you’re more likely to break the battery compartment than you are to suffer damage from a battery leak?
 
What tbone said above is correct. Here's the longer version...

Batteries leak when they are discharged. In some appliances, when the whateveritis is turned off the battery is still connected to the circuit. Even though the device may not be in use there may still be a small current draw which slowly discharges the battery. (I'm having flashbacks to 1980s transistor radios, so I'm gonna run with that image). So, we go on vacation, bring our little transistor radio, come home from vacation, unpack, put radio in a drawer, forget about it until next vacation. In the mean time, the battery slowly discharges whatever is left of its initial charge, and when discharged it starts to leak. We take the radio out to pack for our next vacation, it won't switch on, we open the battery compartment to a gooey, corroded mess. Throw radio away, buy new one at the airport.

Note that it takes many weeks or months for that to happen, it is not an overnight process. And yes, batteries not installed in a device will gradually self-discharge and leak but that is a much, much slower process (years).

On most guitars, when the cable is unplugged the battery is physically disconnected from the circuit (because the barrel of the plug is necessary to completes the battery circuit). When the cable is not present the battery is electrically in exactly the same state as it would be if it was physically taken out of the guitar. That means you are no more likely to have the battery leak in an unplugged guitar than to have the battery leak sitting on a shelf.

And BTW, Energizer batteries have a "No Leak" guarantee or they will repair your device at their cost.

In the worst case scenario, battery compartments are cheap and easy to replace and no other damage will occur to your instrument.
 
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Ok, outing myself here as being heavily affected by OCD when it comes to guitar and camera gear (not the sock drawer kind OCD as my wife will attest to). Exacerbated by a recent NGD in form of that lovely green Jp15, I found a way to reign in my hatred for anything essential that is battery operated - especially guitars or effect units etc. But it’s a fact of life for the JP series or anything piezo equipped like an acoustic: QR codes! I started creating maintenance sheets in my Apple iCloud account (google etc would work as well) for each instrument, amp, etc that requires schedules (or unscheduled) work. So, that puts serial number, some photos, string gauges, tuning, date of last string change/fretboard cleaning/waxing, date of last battery change (ding ding ding), etc in one place.
Simple $2 iPhone app to create QR codes (with a link to the respective file) to stick on the case or even the back of the guitar and your good to go.
Obviously, a simple calendar reminder, sharpy date on the battery or a piece of paper will do the same - but it’s a lot less geeky and oddly satisfying.
Decided to keep measuring with current use to see if a 6 month schedule will work.
 
Good solution! I've always logged maintenance work in a logbook, and use tape/sharpie on my amps (for tube dates).
 
Thanks for the info on the battery. It was driving me nuts that the battery keeps draining out even when I am not using it. From now on, I guess I will keep it unplugged when not using it.
Another question, though: why don;t the humbuckers work even when the battery is drained (or if I would take it out)? The magnetic pickups should work without any electric assist, right? I know the JP15 has a boost feature on the knob, so maybe that winds up connecting the pickups through the battery? Bummer. I should be able to play without a battery if I want to (or have to, if I get a bad battery)! Thoughts?
 
Nancy JP said:
Thanks for the info on the battery. It was driving me nuts that the battery keeps draining out even when I am not using it. From now on, I guess I will keep it unplugged when not using it.
Another question, though: why don;t the humbuckers work even when the battery is drained (or if I would take it out)? The magnetic pickups should work without any electric assist, right? I know the JP15 has a boost feature on the knob, so maybe that winds up connecting the pickups through the battery? Bummer. I should be able to play without a battery if I want to (or have to, if I get a bad battery)! Thoughts?
Click to expand...

Simply put, the JP15 has a buffered output which requires a 9V battery (so does the boost), which is why it won't work with a dead battery, or without a battery installed.
 
It is possible that a faulty preamp can eat batteries without having a cable plugged in. Happened to me. If you suspect this, you can easily diagnose using a regular cheapo meter to check voltage to the preamp with the guitar unplugged. Not saying it's a common issue, but it has happened.
 
Yeah, thanks (really). After I posted my comment I looked more closely at the diagram and it makes clear that the pickups go through the same circuit as the pre-amp. I see why they did it, so they could easily boost it with the pre-amp, but I still kind of like the idea that the magnetic pickups ought to be able to work without a battery. Old school, I guess. I would have preferred if they wired it so that the pickups go through the pre-amp circuit only if you have the booster button on. Might have cost them 10 cents more, I suppose. Oh well, it's a great guitar.
 
In general, a guitar or bass with active electronics will not work if the battery is dead, unless it has been designed to bypass the preamp. The "noiseless circuit" is an exception, as the signal is not routed through it, rather the silent circuit is like a 4th pickup that is attached in the switching scheme.
 
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