Best Book for FFT+Application (Musical Instrument)

[ChepRidwan]

I want try to make a real time guitar tuner, but someone tell me, I must use FFT to processing signal to find the fundamental frequency from the instrument (Guitar), It's true?.
I need a book (best book) for study the FFT, for musical instrument. Anybody Know?? Help me...
Do You have Source Code programs (VB or Delphi) for Real Time Guitar Tuner (Using Sound Card)?

 

[Learner]

You can use DSP to make a digital bandpass filter with hi Q with preset bandpass frequency for each note you try to tune, then use display such as leds to indicate the level to see if the notes are in tune with the passband frequency.

Alternatively, you can make an analog circuit to do this as well.