Passive/Active

[Bassymmetric]

Sorry if this has been covered, didn't have time to search.

I'm in a bind. I purchased a piezo bridge pu and I have soap bar pu as well Bridge is active, others are passive. Is it possible to wire the active pre-amp for the bridge along with the passive pu into one jack?

 

[mikezimmerman]

No. However, you might be able to run the passive pickup through the same preamp that the piezo bridge is using.

 

[line6man]

You just need to be worried about the impedances.

Piezo pickups have a VERY high impedance capacitive output.
Passive pickups have a fairly high impedance inductive output.
Preamps/active pickups have a low impedance output.

You will need buffer circuits to get the impedances lowered if you want to run piezo or passive pickups on the same output as the preamp.

 

[Bassymmetric]

Hmmmm.....sounds like something I may need more expert advise on. I have a limited working knowlegde of circuitry.....Where would this buffering need to occur? Between the pu and the pre-amp? Or between the pre-amp and the output? Also, are we talking capacitors to accomplish the buffering?? If I had specs on the impedence of either PU would that help my cause?

 

[line6man]

Hmmmm.....sounds like something I may need more expert advise on. I have a limited working knowlegde of circuitry.....Where would this buffering need to occur? Between the pu and the pre-amp? Or between the pre-amp and the output? Also, are we talking capacitors to accomplish the buffering?? If I had specs on the impedence of either PU would that help my cause?

Between the passive pickups and the output, as well as between the piezos and the output.

You're thinking of capacitive coupling, which is not what we're talking about here.

You need an active component (transistor) to create a buffer circuit.

I believe that EMG may sell a buffer unit of some sort.

 

[Bassymmetric]

I believe that EMG may sell a buffer unit of some sort.

Mighty Might makes a pre-amp but I'm guessing you're not talking about a pre-amp.....although I will need one for the piezo pu. Would something like that be a specialty item for guitar electronics or could I find something at a specialty electronics store? (Not Radio Shack)

Thanks again!