Using NPN transistor to make piezo beep louder

i have keypad connected, sketch understand keys , works fine.

now want make little beep whenever key pressed - using piezo buzzer here:
http://www.hobbytronics.co.uk/arduino-tutorial7-piezo-beep

here actual product page:
http://www.hobbytronics.co.uk/piezo-transducer-5v

i says in tutorial, , works fine.

but beep quiet - want make bit louder.
i copied circuit here:

http://startingelectronics.org/beginners/circuits/arduino-buzzer/
i using second circuit external power supply. have external 9v power supply instead of battery. connections in lower diagram on page.

but no sound @ - faint click. 

i using p2n2222a transistor here:
http://uk.rs-online.com/web/p/bipolar-transistors/5449624/

i have 4.7k resistor between arduino pin , transistor base.
i have tried 1k , makes no difference.

can tell me missing?

many in advance.

quote

can tell me missing?

you missing did not followed. clear photograph of setup scaled 1000 pixels wide allow check sorts of things not know about.

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