Never underestimate the power of simple synthesis tricks, least of all in the hands of vintage Casio designers. The distinctive “frog” bass croak in Michael Jackson’s “Thriller,” recorded in 1982, comes from a Casiotone MT-60. And it’s a sound you can patch up yourself.

I completely missed this discussion when it was happening last fall – Halloween tends to resurrect MJ’s iconic hit. But Anthony Marinelli’s video investigating it is a fun treat for everybody. Steven Ray (assistant to Quincy Jones), Matt Forger (who wrote the track sheet), and Greg Phillinganes (keyboardist, session musician and a legend himself) all chime in.

I will never understand why Casio isn’t bringing back vintage instruments the way Roland, KORG, and Yamaha have. But while we ponder that mystery, Casiotone synthesis techniques are making a comeback in the modular realm – methods like phase distortion synthesis can take on new life in the 21st century for anyone bored of the same vanilla subtractive synth noises.

In this case, the reason this sounds so distinctive is something Casio dubbed “Consonant-Vowel synthesis.” (You can catch up with a history of Casio keyboards from the era.) The idea is pretty simple – take two independent multipulse waves ( the equivalent of consonant and vowel), process them separately with their own envelope-controlled filters, and mix them back together again. It’s something you can reproduce in any modular synth easily – see below. This being Casio, they came up with an ingenious way of pulling it off cheaply, as detailed in an official writeup the company in honor of the 1980 debut’s induction into the National Museum of Nature and Science, Tokyo as “future heritage technology”:

The Casiotone 201 is a small electronic keyboard that used a sound source called the “consonant and vowel” system, a revolutionary approach for the time that generated two LSI types for the sound waveform, one for the beginning of the sound (the “consonant”) and one for the decay (the “vowel”), and then merged through two sounds through a process of D/A conversion. 

Casiotone 201

Casio has brought this back in an unlikely place: it’s on the ST-1000V, one of their more interesting instruments in recent years.

Also last fall, I missed that Grant of Dome Music Technologies recreated this in Cherry Audio’s Voltage Modular:

The “Thrilling” Casiotone MT-60 Frog Preset in Voltage Modular! [with download links]

Yes, yes, old news from 2023, though even older news from 1984 that was actually recorded in 1982. But it came up on X today, so I’m guessing I wasn’t the only person who missed it and – evergreen, like froggies.

Anyway, sound designers, I challenge you to make this frog sound next.

I have fond memories of Thriller, because – this will date me, sorry – I heard it first in a brand-new special edition 1984 Pontiac Firebird Trans Am, with all the extras. I was in kindergarten or first grade or so, and this was carpool with the, uh, rich kids I went to school with, evidently. We shut the door, and they popped in the cassette of Thriller. It felt like I’d fallen into a futuristic dream. Literally, it was this car:

(That early 80s theme from Pontiac’s agency was dorky. By 1988, they ***ing killed it. I … may have gotten off-topic again.)