Playing with a synth (microKORG) and an analog scope

I show a scope view of : a sawtooth wave, a square wave, a triangle wave and a sine wave. I then play some notes together (C's major third and perfect fith for better results) to show waves addition. After modulating the sine wave, I play some notes together on each of the basic waves, again to show waves addition. I then play a square wave and modify the cutoff so you can see some harmonics disappear/appear. Finally, I increase the resonance, thus boosting the harmonics around the cutoff frequency.

• Category

  Science & Technology

[John Wedgeworth]

Is that FM going on at the 1:05 mark? Looks like its based on a sine wave.

Sega Genesis uses square psg and sine based FM.

I've always wondered how something as soft and smooth as a sine wave could become so edgy and expressive as the Sega Genesis sound system, but if 1:05 is an FM event, then I can see it in action. I've definitely heard sounds akin to that on my Sega!

Very cool video, btw! :-)

[eeppeliteloop]

Here is the relevant section of the synth owner manual : 0x3b.org/ss/catalyzers828.png (look at 3-2). So it's kind of FM, but very basic.

[Pam Khan]

I think this is the most beautiful video I've seen on Youtube, ever.

[eeppeliteloop]

Thanks! Would you like me to post a more complete one? This was a cheap camera and I only recorded a few experiments.

[Alexis Martins]

yes, oh please yes!!!!! where have you bought this amazing video scope thingie?? so cool!

[eeppeliteloop]

A modern, digital oscilloscope is well into the thousands of dollars, but I got this (really) cheap used unit for $30. It's a 30-MHz, 2-channel B&K Precision, probably from the 80s.

[John Wedgeworth]

Okay, thanks man! I do love this video. I've linked friends to it when I'm trying to teach them the difference between sine, square, saw, and triangle. This is a great resource for that!

Also, I only barely understand what fourier means and how it works. I'm assuming the part towards the end where you're changing square waves to sine waves, and then back again is fourier. (sorry for that sounding so imprecise.) :-)

Thanks!

-J

[oakpinemaple]

sweet! could watch and listen for hours...

[Gorskah]

Same here :D I was amazed.

[SquareWaveHeaven]

The beauty of music. The beauty of maths :)