A tuning device for musical instruments

Thanks for the replies from everyone ,
but i was hoping for more of a intricit analysis of the electronic components and parts required, and their functions, for this device . eg. i know i have a condenser mic that transforms the sound into a a.c. output which is amplified and filtered through a band-pass filter (actice filter maybe, i'm not entirely sure!) this then goes into a PLL IC (probably a 565 (linear) PLL!) to give a d.c. output the reference signal, which seems to have a quartz crystal oscillator going in as well but the reference frequency from the crystal needs to be say concert A=440Hz and quartz crystals generally vibrate at 20MHz so how do i use that? i think i need a frequency comparator a frequency synthesizer so maybe TWO PLL's then the output drives a dial (analog as i don't want digital programming to complicate the overall design!) indicating the pitch being sharp or flat and LED's indicating the note (it's for a violin so there are only the four notes G=? , D=? , A=440Hz and E=? )! :?:
Best regards,

my idea:

input 1hook up a microphone to a frequency to voltage converter.

input 2abstable 555 timer running at 440 hz to another frequency to voltage converter.

use these two inputs in a voltage comparotor.