RE2-YM3812/3526 - Project RE:birth 2nd Sound Card
What is it?
Project RE-birth 2nd is the spiritual continuation of Project RE-birth — a legendary open hardware project dedicated to bringing classic FM sound chips back to life.
In 2021, for unknown reasons, the Japanese closed the ym2203.com website, deleted all public schematics, and stopped the distribution of all peripheral hardware. Even with money in hand, it became impossible to purchase any SPFM motherboard or rebirth module. This was deeply frustrating for enthusiasts worldwide.
In the absence of original hardware, I forked almost all RE-birth music modules to truly revive this project. My mission: make FM music chips available to people all over the world — no internal meetings, no mystery stores, no hunger marketing, just long-term stock and fair play for everyone.
The RE2-YM3812/3526 is a multi-variant OPL2/OPL sound card for the SPFM series, supporting three chip options: YM3812 (DIP24), YM3812-F (SOP24), and the classic YM3526 (DIP24). The circuit is fully redesigned and compatible with the RE:birth bus.
About the Chips
The YM3812, also known as OPL2 (FM Operator Type-L 2), is one of Yamaha's most iconic FM synthesis chips. It features 9 channels of 2-operator FM synthesis and was the heart of the legendary AdLib sound card and early Sound Blaster cards. Its distinctive FM sound defined PC gaming audio throughout the late 1980s and early 1990s — from early id Software titles to countless Sierra and LucasArts adventures.
The YM3526 (OPL) is the predecessor to the YM3812, offering similar 9-channel FM synthesis and used in early arcade hardware and home computers. It is increasingly rare and sought after by collectors.
The YM3812-F is the surface-mount (SOP24) variant of the YM3812, offering identical functionality in a more compact package.
Key Features
- Three chip variants: YM3812 DIP24, YM3812-F SOP24, YM3526 DIP24
- 9 channels of 2-operator FM synthesis (OPL/OPL2)
- AdLib and Sound Blaster compatible
- Compatible with RE:birth bus standard
- Works with SPFM Light, SPFM Lite, RESPFM, IAP-RESPFM and more
- Classic NE5532 dual op-amp for excellent audio output quality
- Adjustable volume control on-board
- Excellent digital-to-analog isolation for clean, noise-free sound
- Standardized RE:birth module form factor
- Long-term stock on YM3812 — fair play, no artificial scarcity
Supported Chips
- OPL2: YM3812 (DIP24), YM3812-F (SOP24), U6612
- OPL: YM3526 (DIP24)
Compatible Mainboards
- SPFM Light
- SPFM Lite (2 slots)
- RESPFM
- IAP-RESPFM (4 slots)
- STM32-RESPFM (4 slots)
Compatible Software
Open Source
Hardware design available on GitHub: github.com/denjhang/RE2-YM3812_3526