Stupid bass question?

[JayDawg]

I know many guitars and basses have a Piezo pickup in them. I even owned a guitar with one once but I have never understood the purpose of the piezo pickup. Can someone explain to me the piezo in very simple laymen's terms?
Thanks!
Jay

 

[LawDaddy]

It sounds like an acoustic guitar. So you can switch between "electric" and "acoustic-y" sounding parts without switching guitars. If you watch the latest Rush Time Machine DVD, Lifeson has two cables on his guitar, one runs the piezo to one rig for the acoustic parts, and the other runs to his regular rig.

 

[ubnomnar]

Piezo pickups also add "life" to the sound of a bass when blended with the magnetic pickup. I'm a big fan of the piezo option on EBMM basses.

I borrowed the following from Guitar pickups made simple

"Piezo" is a Greek (what else?) word for "pressure" and piezoelectric means simply some crystals that, when any pressure is applied on them, they produce tiny amounts of electricity.

So these piezo pickups are mounted on the body (resonator) of the acoustic guitar and they vibrate. This vibration acts as tiny pressure on the piezoelectric sensor, which produces electrical signal identical to the vibrations. Then it goes again to the guitar amp. Smart, hm?"

 

[TheAntMan]

Can someone explain to me the piezo in very simple laymen's terms?

OK. Adds a tone you can't get otherwise.

Hope that helped

--Ant

 

[JayDawg]

It sounds like an acoustic guitar. So you can switch between "electric" and "acoustic-y" sounding parts without switching guitars. If you watch the latest Rush Time Machine DVD, Lifeson has two cables on his guitar, one runs the piezo to one rig for the acoustic parts, and the other runs to his regular rig.

When I bought my electric guitar with the piezo in it, that is what I was told, is that is gives the guitar an acoustic guitar sound. That guitar also had 2 inputs too. One for the piezo and the other for the regular pickups.

So if I'm understanding things right, on an EBMM bass or guitar with a piezo option, there are no dual input jacks, just a blend knob correct? If so, eventually, one of my EBMM basses that I buy in the future will have a piezo option.

 

[adouglas]

I respectfully disagree that a piezo makes an electric instrument sound like an acoustic one, or even "acoustic-y." I own two basses with piezos and there's no way I can get them to sound like acoustic instruments.

Piezos are "acoustic" pickups in the sense that they sense physical vibration and translate that into current. Indeed, most amplified acoustic guitars use a piezo pickup under the bridge.

But acoustic tone has a heck of a lot more to do with the physical nature of the instrument than with the pickup. Your bass unplugged does not sound like an acoustic instrument. Why would a piezo pickup magically change that?

The piezo does indeed give you tone that you cannot get from a magnetic pickup. But sounding like an upright bass or even one of those massive acoustic bass guitars, not so much.

Correct on the way it's wired in EBMM basses… there's a blend knob.

Here's a simple(ish) explanation of what the piezo actually does.

1. With a magnetic pickup, the metal string moves through the magnetic field created by the pickup's pole pieces. This creates a small current in the pickup windings. That's your signal.

2. In a piezo pickup, this does not occur. Piezos are made from crystals that have an interesting property… when you exert pressure on one, it produces a current. (The reverse is true too… when you run a current through a piezoelectric crystal, it moves. That's how piezo tweeters work.) So… if you put a piezoelectric crystal in the bridge saddle, it will sense the physical vibration of the string (and the bridge, and the body….) and turn that into an electric current. In other words, the piezo is picking up the ACOUSTIC vibrations of the whole string-plus-instrument combination. The magnetic pickup only senses the movement of the metal string through the pickup's magnetic field.

 

[JayDawg]

Thank you for that explanation adouglas! Do you have any recordings of your basses where you are using the piezo?

 

[adouglas]

Thank you for that explanation adouglas! Do you have any recordings of your basses where you are using the piezo?

No, sorry… there are some good clips floating around on Youtube of piezo-equipped EBMM basses… I think there's one of a piezo Sterling that I've seen. Don't have any specific links but they shouldn't be hard to find.

 

[keko]

From my point of view piezo actually do sounds more acoustic on electric bass.

Piezo rises up harmonics and sounds more "bridge"..., it's integrated in each bridge string saddle anyway, ...piezo sensors on EBMM basses are placed uder the each string in each string saddle and piezo preamp is placed usually under the bridge somewhere!

Check this video for more info and sound sample:

2001 Sterling H with piezo bridge - YouTube

 

[JayDawg]

No, sorry… there are some good clips floating around on Youtube of piezo-equipped EBMM basses… I think there's one of a piezo Sterling that I've seen. Don't have any specific links but they shouldn't be hard to find.

I found the one video one the guy playing a Sterling 4Hp last night. He did a really good demo of the piezo when it was not in use, when it was in use and when it was blended. I really like the piezo option now. Once again hats off to what EBMM has done with something where others have not done as good of a job!