F2 has been set flat so that it produces beats
when it is played with A4 or the fork.
You have to tune A4 so that
the beat speed produced when F2A4 is played,
is the same speed as the beat speed produced
when F2Fork is played.
Remember from the last lesson that this would mean
that A4 and the fork are both the same amount sharp
of the 5th partial of F2, hence they are the same pitch.
If you don't understand this, spend some time
trying to figure it out. It's important.
In other words, make F2A4 = F2Fork.
The beating you will hear is at A4.
In this level, you will see the beat speed displayed
on the screen.
Just tune A4 until the beat speed of F2A4 = 4.4 bps,
which is that of F2Fork.
You will also hear the beat speed filtered around A4
so that it is easier to hear.
I have also added the buttons for F2Fork and F2A4 unfiltered,
so that you can start trying to hear the filtered beat
within the unfiltered waveform. Use them to practice.
F4Fork = 4.4 bps........F4A4 = 3.4 bps
Raise and lower A4 until F2A4 is the same speed as F2Fork, i.e. 4.4bps. Then click [Score]Practice hearing the beating with these unfiltered intervals:
You need to get 100% (i.e. within 0.5 cents)
to go to the next lesson.