Cherry Audio Forums

Anthony Marinelli is a great source of authoritative information on the recording of Michael Jackson's Thriller album.

He recently uploaded a couple of videos to YouTube explaining the origin of that spiky / croaky bass sound in the title track:

MJ's Thriller Frog Bass - The Search

MJ's Thriller Frog Bass .... Found!

It turned out to be a Casiotone MT60 home keyboard. I sampled the sound at C#, which is the key of the song. I then imported it into Sampler 1 and adjusted the root note down a semitone.

Here is a single cycle of the waveform:
Here is the VM patch:

Of course, the next challenge is to synthesize that waveform from first principles using Voltage Modular!

Here's the original sample to help you with your analysis:

Here's my first attempt at synthesizing the sound using VM.

OK, I think this is as far as I want to take this patch. In this variation, I've utilised a Crossfade module to provide a simple envelope-controlled wave-blending function. This mirrors the Casiotone "Vowel-Consonant Synthesis Method".

OK, absolutely, 100% my final take on this patch. This time, I've used only free-of-charge modules:
Voltage Modular Nucleus

Oscillator x 3
Envelope Generator x 2
Amplifier x 2
Glide

Dome Music Technologies

Simple Amplifier x 3
ACE Compare x 2
ACE Constants

Synthetic Future X R_Ware

Micro NOP x 2

Demo of Frog 13 Free patch with a General MIDI backing of Thriller:

You Tube link