Does it just run an FFT and compare the peak frequency with known notes? Run a power spectrum and test against max energy? Or is it doing something else?

While I'm at it, how is a chromatic tuner better? Does the non-chromatic just know the 6 strings of your guitar (or whatever instrument it's for), while the chromatic knows all the notes? If that's the case, why are chromatic tuners so much more expensive? I'm a programmer, there ain't much difference between searching a 6 element table and searching an 80+ element table.
I believe it has something to do with frequencies and how they pick up.

(Eg; 440 is standard tuning if I remember correctly)

Also, while 'searching' the table, it has to be able to pick up those frequencies. The chromatic tuner is able to pick up more frequencies.

(It's like asking why buying a guitar with better pickups generally costs more.....)

I'm more of a coder, less of a programmer though... so...

Please add me if as a friend I helped! (I like to think I'm a friendly person)
Last edited by Invokke_Havokk at Mar 12, 2009,
There you go yes it analizes freq. and compares them to the set most tuners alow you to change the freq.
it just measures the input signal and displays the note relative to how many Hz are being input. concert A = 440Hz, and all other notes are tuned relative to that.

chromatic is better because it shows you all 12 notes, whichever you are playing.

a non-chromatic tuner will only tune to E B G D A and sometimes C or F. non-chromatic tuners sometimes have a special function to tune to Eb or Ebb, so all the notes are achievable if you know how to work the note names, but a chromatic tuner is way more convenient.
Last edited by frigginjerk at Mar 12, 2009,
Frequencies. Thats really it. I'm also a programmer (Computer Science Major specifically) and I know what you mean. Chromatic tuners are more expensive because they are able to pick up more of the notes than a normal "Guitar Tuner". Chromatic tuners can tune guitars and any other instrument. You could tune a fish if it made a sound.

And "Guitar Tuners" usually allow you to tune to drop d, half step, and sometimes a few other tunings too, along with a bass guitar.
(It's like asking why buying a guitar with better pickups generally costs more.....)

Better pickups relates to a better analog front end on the tuner. Better components equals more money, even if the digital backend is identical.

"Searching the table" means the tuner sees, say, 442 Hz. The table has an entry for 440, and one for 466. So it's gonna decide we're playing a slightly sharp A4 note. It might also do linear interpolation to tell you how sharp the A4 is, or how flat the A4# is (A4 is 440Hz, A4# is 466).
Last edited by Snotnose at Mar 12, 2009,