will 9vDC harm a guitar pickup?

[tempus fugit]

Hey all;

Will 9vDC damage a guitar pickup? I have a piezo pickup in my electric
guitar, as well as 2 magnetics. The piezo provides acoustic sound and
connects to my pedalboard on the ring of a TRS phone plug. I'd like to put a
buffer amp inside the guitar and phantom power it from my pedalboard by
putting 9vDC on the ring of the pedalboard input jack. However, if I do
this, the tip of the plug (which will be connected to my magnetic pickups)
will come in contact with the 9v as it pushes past the ring connector on the
jack. Could this cause harm to my pickups? Also, if I were to connect a
normal (i.e., 2 conductor) plug to the input, for use with another guitar,
the 9vDC would be shorted to ground. I know that the 78xx series of
regulators have short circuit protection, but would it withstand being
shorted to ground for an extended period of time?

Thanks

 

[Tom Biasi]

Hey all;

Will 9vDC damage a guitar pickup? I have a piezo pickup in my electric
guitar, as well as 2 magnetics. The piezo provides acoustic sound and
connects to my pedalboard on the ring of a TRS phone plug. I'd like to put
a
buffer amp inside the guitar and phantom power it from my pedalboard by
putting 9vDC on the ring of the pedalboard input jack. However, if I do
this, the tip of the plug (which will be connected to my magnetic pickups)
will come in contact with the 9v as it pushes past the ring connector on
the
jack. Could this cause harm to my pickups? Also, if I were to connect a
normal (i.e., 2 conductor) plug to the input, for use with another guitar,
the 9vDC would be shorted to ground. I know that the 78xx series of
regulators have short circuit protection, but would it withstand being
shorted to ground for an extended period of time?

Thanks

A little clarification please. You can't just put 9 volts somewhere, it has
to be 9 volts with respect to another point. Where is the other point? If
your pickup also shares these two points you may do damage to the device.
I'm not sure what you want to do with the regulator, but no, I will not
'like' to be shorted that's why its protected against it. It will shut off.
Tom

 

[tempus fugit]

A little clarification please. You can't just put 9 volts somewhere, it has
to be 9 volts with respect to another point. Where is the other point? If
your pickup also shares these two points you may do damage to the device.
I'm not sure what you want to do with the regulator, but no, I will not
'like' to be shorted that's why its protected against it. It will shut off.
Tom

The 9v would be with respect to ground - the same ground that the pickups
would be connected to.
When you say 'do damage to the device' which device are you referring to?
The pickup or the buffer amp?

Thanks

 

[Michael Black]

Hey all;

Will 9vDC damage a guitar pickup? I have a piezo pickup in my electric
guitar, as well as 2 magnetics. The piezo provides acoustic sound and
connects to my pedalboard on the ring of a TRS phone plug. I'd like to put a
buffer amp inside the guitar and phantom power it from my pedalboard by
putting 9vDC on the ring of the pedalboard input jack. However, if I do
this, the tip of the plug (which will be connected to my magnetic pickups)
will come in contact with the 9v as it pushes past the ring connector on the
jack. Could this cause harm to my pickups? Also, if I were to connect a
normal (i.e., 2 conductor) plug to the input, for use with another guitar,
the 9vDC would be shorted to ground. I know that the 78xx series of
regulators have short circuit protection, but would it withstand being
shorted to ground for an extended period of time?

Thanks

Huh?

The very notion of "phantom power" means superimposing DC power along
a line that is used to carry an audio signal. By its very definition,
it takes both signals into effect.


You couple your pickup to the line with a suitable value coupling
capacitor, which means the pickup will never see DC. Then at the other
and, there is another coupling capacitor before the signal hits the
preamp, so it will only see the audio signal, no DC.

Then, the audio line can be at any DC voltage, the audio signal will
never notice. You couple the DC in at the preamp side with a resistor
of suitable value (you'll want it to be a reasonably high value resistor
so it doesn't load down the audio circuit, which of course is why there
is a limit on how much power you can draw from this, since the larger
value resistor will become a larger part of the circuit the more power
is pulled through it), and then at the guitar end, you have another
resistor to pull the power off the audio line.

Michael

 

[Phil Allison]

"tempus fugit"

Will 9vDC damage a guitar pickup? I have a piezo pickup in my electric
guitar, as well as 2 magnetics.

** No.

The piezo device has near infinite DC resistance while the magnetic ones
will have about 5 to 10 kohms - making the heat dissipation miniscule.



...... Phil

 

[neon]

Do not put a battery anywhere without knowing where the current is going to flow and how much. a"d" cell can spply enough curren to blow many devices including 100 w speakers.