Tired of buying 9 volt batteries?

[bassbenj]

When you own a herd of active basses after a while buying new 9 volt batteries and putting them in starts to be a drag. Well the thing that set me off was: 1. It's time to rebattery all the active basses again. 2. I bought a 9 volt power supply to power some of my guitar pedals.

And then it dawned on me! Hey, Guitards have solved the 9 volt problem long ago for their arrays of pedals! And looking at the supply I bought: a 1spot (www.VisualSound.net) from GC, I noticed just how cool it was for cheap! It plugs into any voltage power line and adjusts without any switches. It puts out nearly 2 amps. It's got protection against shorts and all other stuff out the wazzoo. With Clean, Silent 9 volt power. In short, it's THE ANSWER!

So clearly all I needed to do was build a box that the 1 Spot plugged into and use a stereo cord to power the active bass through the shorted battery clip. This requires a bass that uses the "ring" terminal on the jack as the battery switch and won't work with basses that actually have a true stereo output capability. Also won't work with basses with a separate power switch on the jack. But happily nearly all active basses use the "ring terminal" trick.

As you may or may not know, shielded stereo guitar cords are nearly impossible to find. [usually "stereo" cords with 1/4" plugs are unshielded for headphones or the like] So as usual, I just decided to build one the usual way: A nice rubber covered cheapo XLR mic cable and munch the ends off it (save for other projects) and install a nice stereo 1/4" plug. The power box goes on the other end. Also I added a 10 Ohm resistor and cap for filtering noise and to eliminate any problem when the stereo cord is plugged into the bass and the power shorts out...lessee 9 volts divided by 10 Ohms = less than one amp...WELL under the 1SPOT rating. (The 1SPOT is also short-protected, but better belt AND suspenders!).

Here's the final wiring

http://www.mrk-inc.com/users/fjacoby/dcpwr.bmp

Note that the stuff to build it comes mostly from a trip to Radio Shack (RS stock numbers supplied)

Here's what the final setup looks like (cover off box):

http://www.mrk-inc.com/users/fjacoby/dcbox.jpg

Biggest hassle is adding the copper shielding to keep the hum out. Note I built it with a mono jack for the output so you can plug in ANY normal guitar cable rather than hard wiring one like the power side. A minor change. You DO want the power side hard wired, however so you don't put 9 volts on your bass' output when plugging into a powerside jack! ["tip" hits "ring" (9v !) first as you would slide the plug in. This is only a problem plugging into the BOX not plugging into the bass. At the bass the problem is "ring" shorts out as you plug it in.]

Note that the 10 Ohm resistor will overheat if you leave the terminals shorted for more than a short time. So it would be best to develop the habit of plugging the system together FIRST and then plugging in the 1SPOT LAST. But momentary shorts as in plugging and unplugging basses appears to be no problem. But remember that this device has not been tested to any degree yet, so it's really still in development. There may be better ways to wire it.

Anyhow... I shorted a battery clip (in photo) and installed it in my MIM Fender Jazz V deluxe et Voila! AC power. No hum or noise! And best of all NO MORE BATTERY BUYING... well except let me note that IF your AC system should somehow die it is no big deal to open the bass and slap a 9 volt battery (which we all carry for emergencies, right?) back in there and finish the gig!

I LOVE THIS THING!
Check it out!
[No I don't work for VisualSound...but cool is cool!]

[Kwesi]

Nothing wrong with your solution but I only ever have to change batteries 2-3 times a year and with 2 basses that makes 6 batteries a year. That one pack of 9Vs a year. Is it really that troublesome or do your basses chow down on 9Vs?

[darkstorm]

I recently changed the batteries in both my basses. Had lost track of how long theyd been in the basses. The batteries where still working well, just tiny bit of detail loss in comp to new batteries. Both had been in the basses for 7 months. Trading battery for another cable from the bass for wallwart power supply makes no sense at all to me.

[bassbenj]

Originally Posted by Kwesi

Nothing wrong with your solution but I only ever have to change batteries 2-3 times a year and with 2 basses that makes 6 batteries a year. That one pack of 9Vs a year. Is it really that troublesome or do your basses chow down on 9Vs?

Of course the main axes use more batteries than the ones just sitting, but I still like to refresh them all about once a year just for drill. So I end up with about 6 batteries plus the usual ones. So Yeah, maybe it's a 10 pack. And the hassle is that so many of these basses you have to take the control covers off and some of those just use wood screws which tend to strip out eventually. So It's just one more thing to deal with. The basses with the slide-in holders are the easiest, but still take batteries (some of them take two).

I should mention that the slide-in holders are a problem for this power source because you need a battery-shaped object to effectively short them. A simple battery clip won't do it.

Obviously optimum would be to have this kind of power source built right into your amp. That way you could simply flip on phantom power and go. No cords, plugs, or hassles. But that would be a later stage.

I'll admit that 9 volt batteries are not as prone to nasty leakage as are flashlight batteries in all sizes, but still I get a bit paranoid about loosing some expensive gear to battery goo. I HAVE lost some expensive gear that way, but never a bass. In a way it's worse to forget about an instrument having batteries in it, than to have to change them regularly. That's one reason I make a point to change them ALL at least yearly.

Anyway, nobody has to use AC power. I'm sure lots of guitarists fill their pedal boards regularly with 9 volters too. But then a lot of them also don't! Your choice.

[Chrisk-K]

Changing batteries in an active bass twice a year is the most trivial chore in my life.

[bassbenj]

Originally Posted by darkstorm

I recently changed the batteries in both my basses. Had lost track of how long theyd been in the basses. The batteries where still working well, just tiny bit of detail loss in comp to new batteries. Both had been in the basses for 7 months. Trading battery for another cable from the bass for wallwart power supply makes no sense at all to me.

Not "another" cable, but a "different" cable. There's only one cable to the bass.

[D.A.R.K.]

this is great environmentally.
even 6 fewer batteries ending up in land fill per year is worth it.
say only 100 bassists were do it that use up to 6 batteries a year.
that's 600 batteries a year, which isn't massive but is substantial.
the little things can make quite a difference when they add up.

[Red Planet]

[i_got_a_mohawk]

Could always use rechargable 9v batteries or as Red Planet points out, the mega long life ones.

Must admit that I certainly don't have an issue changing batteries, sometimes I use a wireless setup too, so, y'know, not the most useful of setups for me

[Vincent P]

Same here, only twice a year so no real issue.
Great project but would not work for my MIA Deluxe with 18v (two battery) system ;-)

[rick0link]

............or you can do what I did, eliminate all active electronics and use passive pickups/electronics only.

[waterproofsoap]

It's a great idea from the stance that you will not have to make purchases again, provided your "product" continues to function. My basses chew batteries up...that's because they are being played for 16hrs a week. I'm replacing batteries once every 6-8 weeks. Red Planet has a point though that I have to acknowledge as the best solution....rechargeables or long life....
Although you've gone to great lengths to achieve DC isolation and eliminate hum, a battery solves that issue hands down.
I have even moved along to doing this on pedals when playing guitar....I own dc isolation power taps...none of them provide the guaranteed silent operation that a 9v battery can.
I applaud your effort, you have clearly put a lot of time and thought into this.

[putsia]

This thing in whole cost about the same as one rechargeable battery and the charger and it's a one time investment for all your basses though

[madmatt]

I took the active EQ out of my Fender American Deluxe P and built a box for it. Now my Bass is passive, but if I do want an Active push I go through the box I made. And it will work with any passive bass.

[Red Planet]

Would it be OK if I one upped myself?

When Lithuim Air Batteries hit the streets your 9 volt will be the size of a pencil eraser and will last a lifetime.


http://en.wikipedia.org/wiki/Lithium_air_battery

[MNAirHead]

IF you have 18v basses..there's a simple way to convert them to 9v (most of the time).. costs about $.75.. and is reversable.

PM me if interested.

I own at least 20 active basses... the batteries last years in them.

[Rob22315]

I think this is a great idea (been posted before though).

I'm getting ready to do this for both my 9v and my 18v bass. The design isn't voltage dependent, you simply need to get the right power supply. I've custom built my looper and a small interface box so I can power my guitars from the wall through a stereo guitar cable. I added a DC power jack to the looper and I've ordered parts to build the interface box for times when I don't want my pedal board.

I'm motivated by the environmental aspects of being free of batteries. Batteries in my guitar, batteries in my pedals etc. One or two may not seem to make a big difference but for all the electronics in my house, combined with all the electronics in my neighborhood, combined with . . . You get the picture.

[FunkMetalBass]

Originally Posted by i_got_a_mohawk

Could always use rechargable 9v batteries or as Red Planet points out, the mega long life ones.

Must admit that I certainly don't have an issue changing batteries, sometimes I use a wireless setup too, so, y'know, not the most useful of setups for me

This.

My rechargeable Energizer battery doesn't fit into my quick-change compartment for some reason, so I've never actually gotten to try it out.

[Rob22315]

Here's my plan - I just ordered two 15 ft TRS cables for a little over $30 total. Both ends are TRS. My looper and the stand-alone box are wired with a 1/4 stereo jack, a 1/4 mono jack (the looper actually has 10 or 12 of these), a standard DC (5.5/2.1mm) power jack and an LED to confirm I'm getting power into the box. Since the boxes are metal, I'll use them as the shield. The DC power feeds to the sleeve and the ring while the signal feeds to the sleeve and the tip. Not exactly traditional 'balanced' wiring but not any more offensive shiedling-wise than a mono guitar cable.

The DC power jack let's me plug any standard DC supply I wish. (The one I use is insulated so no issues with shorts.) For the stand-alone, I have a Dunlop 18v supply. For the pedalboard/looper, I'll gang two 9V supplies on a T-Rex Jr together to get 18V.

I ordered the cables from musiciansfriend and the metal boxes/jacks/LEDs from pedalpartsplus. I have some old 9V clips laying around, I'll use those to do the reversible mods in the battery compartment. (Yes, this is all reversible in no more time than it takes to install a new battery.) The only catch is that I have to ensure the only thing attached to the ring terminal inside the guitar is the battery ground. All the other grounds must be connected to the sleeve.

[pasta4lnch]

I think it's a fantastic idea!! Sort of strange to me it's not as well received . . .

if you can send 48volts to a mic, why not 9 to an instrument.

I dunno about you guys, but if there is even a remote possibility a battery will fail during a show, and I'm not using a wireless, I'd use this!