Firtsly thankyou for helping me in my previous questions..
Now as you all know that when ever some one starts to learn microcontroller usually the first project is a Digital Clock... Now i will try to write the codes firstly my self and then ask for any help after wards... My objective of this post is know one thing:-

We can cause the controller to generate different sounds by sending pulses of different frequencies...

Now i want to make a digital clock which after each hours creates a Loud Alram .. but the sound of that alram should be like that of "Big-Ben Clock" in Central London.. ( I hope every one knows that famous Big Ben Sound)..
So i was hoping if some one can guide me which frequency to generate using the controller and what should i attach after controller to make that sound just like big ben and loud...like buffers . LM386 etc..