The pin out information was correct on the G-505 Service Manual Schematics schematic, which uses almost the same circuits.
All the G-303s and G-808s that I have checked have op-amp pin outs consistent with the G-505.
If there is one guitar that has become the "gold standard" of guitar synthesizers, it has to be the Roland G-303 guitar.
No doubt much of the popularity of the G-303 comes from Pat Metheny, who has played this guitar year after year on stages across the world, always amazing audiences with the moving and emotional quality of the G-303 and GR-300 rig.
These op-amps are the top three 4558 op-amps in line with the 24-pin ribbon connector.
IC4, IC5 and IC6 op-amps are used to create the hex fuzz sound. The line-level amplifiers are surrounded by resistors for a simple gain circuit, and the hex fuzz amplifiers have the network of diodes used to create the fuzz sound.
In Los Angeles I have seen jazz players using the G-303 plugged straight into a Polytone amp, just for the sound and playability of this great axe.
In terms of sophistication of design and electronics, the weighty Ibanez IMG2010 comes out way ahead of the G-303, but like the Roland G-707, the IMG2010 is a bit of an acquired taste, and its curious body design means that the Ibanez IMG2010 is virtually impossible to play sitting down without a guitar strap!
For my purposes, I labeled these pickups as "wide" or "narrow." One pickup is around 10 mm wide, and the other is about 12 mm wide.The other vintage controllers, the G-202 and G-505, are well-built, fine guitars.But they cannot escape the feel of being really well made Fender copies, no matter how nice they are. The more expensive G-808 has through-neck construction and other nice features, like gold hardware.From looking at the version "A" photo, it appears the one op-amp is used per string to both amplify the signal and create the hex fuzz sound.If you look at IC6, at the top of the version "B" and "C" card, you can see resistors just to the left of the chip creating gain in the negative feedback loop, and additional diodes just to the right side of the chip for generating fuzz. After years of working with Roland vintage electronics, I finally noticed that there were two variations on the familiar hex pickup.