Feeding current to your guitar???

[Sunbane]

This is a question to the pro people out there.

I recently heard that some people feed 9 volts to their guitars through a stereo tele cord - thus not having to rely on batteries for active electronics. I think this could be a great thing - especially for the sustainer users.

Now, I've played for quite a few years, but I haven't played out in ages, and this is the first time I've heard of such a thing.

Does anybody know how this is accomplished? I figure you would need some sort of driver box that would go in between your guitar and your amp gear? Is there a special term for this sort of arrangment?

[DonP]

Re: Feeding current to your guitar???

It could be done even with a mono cord. You would couple your guitar's pickups with capacitors to prevent DC voltages from frying your pickups. Because your tone is going through a cap, there would be a chance that some bass might be dropped. You'd also need to couple the front end of the amp or whatever you plug into.

Stereo cord would be real easy. You have a separate line for the voltage to come into the axe. Sharing a common ground should be ok.

[RobRR]

Re: Feeding current to your guitar???

With a stereo jack it would be simple. The stereo cable has 3 internal wires. Two positives and one ground. Basically, you would transfer your current wires from your mono jack(2 connections) to the same position on the new stereo jack (which uses 3 connections), and use the 3rd connection as the power, you would connect that to the hot side of your sustainer. Then run the ground from the sustainter to the guitars general ground(which also goes to the ground at the jack). Now, on the other side of the cable near the amp (or what ever your plugging into) youll have to disassemble the male jack end, they usually just unscrew. Remove the 3rd wire your jusing for the 9v from the jack assembly, and attach it to a 9v battery connector. Then, run the ground of the 9v connector to (and in addition to) the cables ground.

Seems like a pretty good idea, Ive never heard of that before! I wouldnt go trying this with a mono jack unless you want to destroy some hardware and make over complicated schematics.

[Sunbane]

Re: Feeding current to your guitar???

Yeah, that's pretty much what I've figured out. Apparently there are guys doing this already.

I figure you could build a "guitar driver" box and put between your guitar and your amp. Between the box and the guitar amp you'd use an ordinary guitar cable. Between the box and the guitar you'd use a stereo cable. The signal and ground wires from the guitar would just pass through the box to the amp. Then you hook the box up to a 9 or 18 volt power supply, thereby completly eliminating the need for batteries. This current would go to the guitar on the third pin (the ring on the tele plug) and go back through the ground wire (like it would under normal battery use).

You could even put a pedal switch on the box to turn the current on and off - and if you'd wish, a pot for capping the current to your liking.

The only potential hazard I can see, would be if the power supply failed in some spectacular manner, sending 220V AC into your guitar. That would be nasty. [img]/images/graemlins/tongue.gif[/img] But I figure you could just build fuses into the box as well, to prevent any such disasters from happening.

EDIT: Another potential disaster scenario would be if some clueless moron plugged in his own passive (or battery loaded) guitar into your gear, and frying his electronics. Therefore it would probably be a good idea to use an XLR cable between the box and the guitar, and modify the guitar jack to XLR accordingly(?). (or just build an XLR to Stereo Tele adapter for your guitar)

What do you guys think?

[Sunbane]

Re: Feeding current to your guitar???

I've investigated this a little, and so far I have found no products for guitars that do this sort of thing. It seems to be very common practice with active studio mics though?

The swedish term for it is "phantom feeding" (my translation). I have no clue what the correct english term is.

The guy I saw mentioning it claimed he has been running a system like this for a few years, but I'm not sure if he was being serious.

I would like to put a sustainer in a guitar with EMG pickups, but I do NOT want to chuck three or four 9v batteries in there! I think a current feeder could be the answer, but I'm not skilled enough in electronics theory that I would be confident in designing a system like this from scratch.

I think in a complex setup like that, the guitar would probably have to be fitted with a few resistors to each chain in the electronics, so that each part would get just the amount of current/voltage it needs - and then the driver box would need some kind of voltage pot, so you could finetune it to your guitar setup?

I also came up with another potential disaster scenario:

...You unplug your guitar for five seconds, and while you put it down on the stand, your ten month old toddler licks the tele plug. Owie! [img]/images/graemlins/tongue.gif[/img]

[rjohnstone]

Re: Feeding current to your guitar???

The english/american term is "phantom power".
Nice concept for powered mics.
I wish someone made an off the shelf item to do this for guitars, but it would still require some re-wiring in the guitar as well.
But not really helpfull for us wireless guys. [img]/images/graemlins/poke.gif[/img]

[Sunbane]

Re: Feeding current to your guitar???

Ah, yeah...the difficulty of transmitting power through air... [img]/images/graemlins/laugh.gif[/img]

[rjohnstone]

Re: Feeding current to your guitar???

[ QUOTE ]
Ah, yeah...the difficulty of transmitting power through air... [img]/images/graemlins/laugh.gif[/img]

[/ QUOTE ]
Mother nature does it very nicely, but I'm not sure I would like to get hit by a bolt of lightening any time soon. [img]/images/graemlins/tongue.gif[/img] [img]/images/graemlins/laugh.gif[/img]