Teensy 3.2 Spectrum analyzer

Other Hardware Science and Measurement
2

const int sampleRate = 16384;
const int timeSize = 1024; //FFT points

Center of each of the 512 buckets:
freq = index * (sampleRate / timeSize)
0 -> DC
1 -> 16 Hz
2 -> 32 Hz
3 -> 48 Hz
4 -> 64 Hz

511 -> 8176 Hz
Each bucket is 16 Hz wide.

I think what the code is doing is dividing the 64 display columns among the 512 values to get an equal change of pitch (not frequency) in each column. Sort of like semitones in an octave.