Oh for sure. Synth DIY is a great list for the solder minded. The guys on there are incredible, there is never any beef, and they are friendly to newbies, and females, you don't get the nonsense you get elsewhere. They go so hardcore into stuff sometimes that it's over most heads, but if you want to know they will break it down. It's mostly about synths, some guys actually cloning old synths very well, many are professional Electrical engineers, some work for NASA, or used to, and they bring their expertise to their hobbies.
Anyhow, I haven't looked at the schematics, If you remember the page number of the voice outs I'll have a quick look soon. But if they are using dual op amps they are either using an inverting amplifier followed by an inverter which will double as a buffer on the output, probably both on the same dual op amp. Inverting amps are cleaner than non inverting, but are more expensive as you need to invert the signal again (needing another op amp) They might be using a non ionverting amp with just a buffer, but considering the market for these things and the time of release, I bet they used the inverting amp, since it has less noise.
From the description given at forat, I think the mod shouldn't be too difficult, perhaps there is an amplifier before all outputs that would bring them up to +4, but it could be adjusting one resistor or a resistor pair per output. Which would take a little time, but nothing too serious.
yeah, it's fun to have DIYers here
