Small battery powered speaker Answered

I basically want to sound the speaker when the circuit is closed.

would this really make the speaker louder cuz i have a speaker and on the back is says this..... so how much voltage would i need to use or would i need to use anything else that would help amplify it?

All that would do is feed power through the speaker - where is this "sound" coming from?

I just want an steady tone, like an alarm. Is there a speaker that emits sounds when powered up?

Here is why what Guy and Zach are saying is true: if you connect a battery to the speaker, it activates the coil and the magnet gets stronger, pulling the cone of the speaker inward, or pushing it out depending on which way you hook it up. Because you have a DC source, it will not change (a speaker needs a "frequency" or changing voltage to make a sound). You may hear a light pop noise, but only one single pop, then silence. The 555 is a timer IC and can be wired to put out a "frequency", and depending on how it is wired, you can alter the tone at will. You may need an amp also if you need any volume.

Thanks for the simple explanation. Makes sense :)

You are welcome, glad I could be of some assistance :-)

you need a 555 timer running in astable mode , don't use the setup shown above, you'd need a resistor somewhere.

http://ourworld.compuserve.com/homepages/Bill_Bowden/page10.htm

speaker with 555