How to build audiometer circuit?

[clubmed7]

First of all..
Anyone can help me to show me the audiometer circuit that produced pure tone to the headphone that separated left and right ear...
Besides that, this audiometer has control several frequencies and decibel values and this values will be display at the LCD screen...
The power input is battery 12V maximum..
Please anyone pro here..
I begging you to help me out from my problem..
I dont want to fail anymore...
ASAP...

[sich]

I personally think that most of the forum participants here are not directly involving in audio circuit. Sorry that i'm not capable to help u too...