Gruber

Pico-8 Frequency Chart

Added 2018-02-16 13:37:14 +0000 UTC

We're still working away on creating a text-to-speech converter for Pico-8.

I explained "formants" in my previous write up. When you say a vowel, formants are the prominent frequencies that give that vowel it's characteristic sound. Each vowel has three (F1, F2, F3)

We decided that in order to transition between formants and vowels, it'd be best to create these transitions using code. This requires having a map of all the frequencies in Pico-8.

So attached is a Pico-8 frequency chart! Maybe you'll find this useful in some way. A few notes:

The rows in green are notes in the normal Pico-8 range (C0-D#5).
You need the instrument editor to get the notes in pink.
The notes in dark pink (at the bottom) are very very high, but (maybe because of human hearing), actually sound lower than they are.
I used instrument 0 for this chart, but I checked how it compared to instrument 4. They were pretty much identical. So these Hz values are universal across all the instruments (except for 6).

A Fourier transform "decomposes a function of time into the frequencies that make it up." (Wiki). Adobe Audition can do this with it's Frequency Analysis window.

Here's what it looks like what it's analyzing Pico-8's 'A2' on instrument 0.

As you can see, there are actually lots of different frequencies at varying amplitudes. But the overall frequency, or fundamental, is 439.75Hz. You can easily see the fundamental because it's the highest peak. All of the other smaller peaks are quieter frequencies called harmonics.

Each instrument has a unique set of harmonics that give it it's characteristic sound. Here's the same note, but using instrument 4: