If you are serious about learning, start by looking up the formulas that will be needed. Write a short piece of code that just does one step, say, converting db to linear value.

The bit about command-line file makes me think that this is a homework problem just typed in verbatim. Do you already know how to read the input with the file name on the command line, or are you totally new to Perl? In that case, start with "hello world".

Also, the name of the language is Perl (and the name of the implementation is perl), not PERL. And we talk (type?) like adults here, even the kids. No IM abbreviations or spam-like titles to get attention -- that will just put people off.

Also, mark your paragraphs. Use the preview!