piezo buzzer is useless (too damn quiet) can i increase the volume?

[aster178]

Hi Ive bought a cheap thermometer alarm and the disc piezo buzzer is so quiet on it it's almost useless, could I replace the buzzer with another piezo that would pack more punch or is it a frequency or current issue? ie this buzzer pictured does have the capacity to achieve loudness if i tinker with it. Or perhaps I should stop being a cheap ass and pay for a better thermometer alarm

 

[andre_luis]

Piezo buzzers in general are designed to work with a large range of supplied voltages.
You should give more details about the device, circuit and battery.

 

[aster178]

Unfortunately not much info on the device but i can add some more pics if that helps in any way...

The battery is a standard AAA 1.5v

 

[andre_luis]

As a blind assistance, what I can suggest is to get the circuit schema that triggers the buzzer and although very unlikely, hope that there is some resistance in series that can be reduced, but the most obvious option would be to try replace the buzzer by another.

Another probable reason, can be the piezo be oscillating out of the frequency range for what was designed, and once again you should get more details about the circuit.

In any case, as a further attempt could also try to carefully replace the wires welded in piezo because probably the fact that are bulky and to be leaning on the device, may be dampening the vibration.

 

[Audioguru]

You do not have a piezo buzzer, you have a piezo transducer (speaker). A piezo buzzer has a built-in oscillator (the piezo has a third wire for feedback) that automatically picks the loudest frequency that it resonates at in its tuned housing.
Your transducer has no tuned housing and its loudest resonant frequency is probably not matched. The 1.5V supply is low but the circuit probably doubles its feed to the piezo.

The easiest way to make it louder is to feed the signal to an amplifier that drives a real speaker.

 

[aster178]

Thanks guys, ill look into some of the suggestions, also this perhaps:

https://www.instructables.com/id/Turn-Nearly-Anything-into-a-Speaker/?ALLSTEPS

 

[jiripolivka]

Most good piezo buzzers resonate at a designed frequency. To supporta reasonable audio output, they are installed in an acoustic resonator ( a plastic holder with a specific volume behind to increase audio output.
Try to locate your piezo transducer over a small cup, or made one of plastic. You will be surprised how much the output can increase

 

[Audioguru]

Thanks guys, ill look into some of the suggestions, also this perhaps:

https://www.instructables.com/id/Turn-Nearly-Anything-into-a-Speaker/?ALLSTEPS

Hee, hee. A comment was made that the author of the Instructable stole the circuit and parts list from an audio book by somebody else.

I betcha the sound is AWFUL! A comment was made that it needs more base (bass). Nobody knows that the transformer steps up the signal voltage to make the transducer's sound a little louder. We do not know if the alarm's output can drive a transformer, probably not.