The JE-8086 is now available, and Giulioz provides insights into the development of the Roland DSP emulator in a new CCC tech talk, including the Supersaw algorithm.
Just before the end of 2025, the Usual Suspect team released the JE-8086, a DSP emulator for Roland JP-8000/JP-8080. Unlike previous emulations, the developers went right down to the core of the synths.
They didn’t emulate the engines, but rather the DSPs; in this case, the Roland chip TC170C140 (ESP2) made by Motorola.
JE-8086: Roland DSP Emulator
One of the developers on this project is Giulioz, who has already reverse-engineered several Roland chips, including Roland TVF (Fujitsu MB87424, 1989), DSP (Toshiba TC23SC260AF-002, 1989), and many more.
A tech talk from the Chaos Computer Club was recently published. In it, Giulioz provided insights into the fascinating development of the latest Roland DSP emulator for the JE-8086. According to him, it was the most extensive project he had ever worked on. There’s a reason for that.
Until now, this information has been a great mystery. Roland has never released any documentation about the chips. Through painstaking work, the developers reverse-engineered the chips using various methods and thus developed the emulator for them.
Many people are praising the JE-8086 emulator; I find it even more remarkable that the developers reverse-engineered this mysterious chip without any documentation.
The Supersaw Algorithm
Additionally, the developers have revealed the long-kept secret of the algorithm that creates the original Supersaw waveform. No developer of any existing JP-8000/JP-8080 emulation has yet captured it as initially intended.
The closest thing so far has been Adam Szabo, who wrote a paper about it and released a very authentic emulation with the Airwave. It’s not perfect for the developers. But the secret is out now, and the technique is surprisingly simple.
Giulioz revealed that the original Roland JP-8000/8080 Supersaw consists of 7 naive saw waves, passed through a high-pass filter without modulation, with no phase tricks or chorus. If you replicate this, the oscillators will alias.
The trick lies in the hardware’s sample rate (JP-8000/8080), which is 88.2 kHz, thus preventing aliasing.
I’m curious to see how many developers will adapt their Supersaw algorithms based on this open-source information.
For anyone who wants to learn how the JE-8086 was developed and how far the developers went, I can only recommend the linked video.
More information here: Guilioz / The Usual Suspects
very Interesting Video!
But the Program Sucks a Lot of Power, from what i have Heard.
It’s installed on my basic M4 and have no CPU issues
Just watched this, and it was a cool and fascinating presentation. They invested some serious work, and it’s nice to see some effort to preserve these older VA synths. Not sure why the companies who made them don’t do something similar.
Owned the JP-8080 for 5 or 6 years, but I sold it because other than the supersaw, I preferred the overall sounds of my Virus C, Yamaha AN1x, and Novation KS4 quite a bit more.