Piezo transducer output?

Discussion in 'General Electronics Chat' started by tracecom, Sep 25, 2012.

  1. tracecom

    Thread Starter AAC Fanatic!

    Apr 16, 2010
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    I posted this question in another thread, but it was a little off-topic and the thread is long, so I am repeating my question here with a little more detail.

    I am planning to use a Piezo transducer as a pickup for an acoustic guitar (which I don't have, yet.) What are the specifications that apply to Piezo's and which ones are most important for my purpose? Are there specific models/types that are better than others? How much output should I expect (Vpp)? Any information is appreciated.

    Thanks.
     
  2. BMorse

    Senior Member

    Sep 26, 2009
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    excerpt from a DIY electronic pickup for an acoustic guitar:
    That being said, I found these piezo's to work really well, I had made a pickup for my son's acoustic a couple of years ago so he could use it with his portable amp, worked really well, and I also used the same piezo's for my E-Drum...
    >>> http://www.radioshack.com/product/index.jsp?productId=2062402


    and here is a link to some good reading and also a simple RLC notch filter circuit to use if needed >> http://dennishavlena.com/dood.htm
     
    Last edited: Sep 25, 2012
  3. Audioguru

    New Member

    Dec 20, 2007
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    Nobody, not even RadioShack know what is their "piezo buzzer".
    It might be a piezo transducer that works like an awful speaker or it might be a piezo beeper with a built in oscillator.

    If it is a piezo transducer then I think its severe resonance at about 3kHz will make a very poor quality audio pickup.
     
  4. BMorse

    Senior Member

    Sep 26, 2009
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    I do not depend on radio shack to tell me anything, as you said they do not know anything about their own products, BUT, I have used this piezo, and I am speaking from personal experience, and this is the only place you can get it readily without having to search for it online somewhere else to order it.

    And it is not used to pickup "audio" per se, but to turn mechanical vibrations into an analog signal.
     
  5. Audioguru

    New Member

    Dec 20, 2007
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    So it is a piezo transducer and not a "buzzer"?

    I watched 2 videos on You-tube about DIY acoustic guitar pickups.
    They both used the same piezo "buzzer" from RadioShack.
    The first showed that it was a piezo beeper with a built-in oscillator and he connected it to the amplifier input and it played percussion sounds. He did not remove its oscillator nor its resonant housing.

    The second video showed a piezo transducer that was removed from its housing. It did not have an oscillator. It was taped inside an acoustic guitar under its bridge and it sounded very good.
     
  6. BMorse

    Senior Member

    Sep 26, 2009
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    Yes, it is just a transducer, no internal electronics used, no internal driver circuit to make it beep or buzz like a buzzer.

    Yes, that is how he should do it also, he will just have to find the "sweet" spot in the guitar for best pickup of the acoustics.

    The RatShack transducer I linked to does not have any internal driver circuit, it requires an external driver to make it a beeper...

    Here it is, I just got 4 to use in a project I am working on for my sons airsoft targets, I am using them as impact sensors to determine how close to the bullseye the pellet hit....
    Piezo disasembled.jpg
    Piezo New in Package.jpg
     
    Last edited: Sep 25, 2012
  7. KJ6EAD

    Senior Member

    Apr 30, 2011
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  8. Audioguru

    New Member

    Dec 20, 2007
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    The first video on You-Tube about a DIY acoustic guitar piezo pickup shows the RadioShack buzzer Beeping when a 3V battery was connected to it. It won't beep without an oscillator inside. The guy connected the wires (that power the oscillator) to the amplifier and it worked fine as a pickup.

    Another video shows a RadioShack "buzzer" with 3 wires on the piezo (the 3rd wire is feedback to the oscillator transistor) and a circuit board (the oscillator) but the guy did not know what the circuit board was for. He also connected the wires (that power the oscillator) to his amplifier. He said that some of the "buzzers" do not have a circuit board (because they are transducers, not beepers).

    So some are beepers and others are transducers but they look exactly the same.
     
  9. BMorse

    Senior Member

    Sep 26, 2009
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    Well, I don't know what video's you are watching, I don't see any links to any video's on here, I posted a specific radio shack part number, I doubt that they would have 2 different piezo's (one with driver and one as plain transducer) with the same part number. So I really do not see the relation to what YOU are watching and what is being posted in this thread.


    again, here is the link to the piezo transducer that everyone uses >> http://www.radioshack.com/product/index.jsp?productId=2062402#tabsetBasic
     
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