The FS1R is an uncommon and complex synthesizer. It's a powerful FM synthesizer, offering 8 operators each with multiple waveforms. But beyond that it also introduced Yamaha's Formant Synthesis technique which can produce realistic vocal sounds. The 8 unvoiced operators also allow you to add complex, shaped noise to your sounds.
Thor Zollinger has written an extensive guide on FM synth programming, particularly with regard to mimicking the sound of "real" (acoustic) instruments.
Smasher has collected a nice list of FS1R programming tips and ideas.
- K_Take offers freeware FS1R editors on both Windows and Mac.
- Matrix made an FS1R editor template for TouchOSC on iPad.
- Thor Zollinger has an FSeq editor for Windows.
- Wouter van Nifterick also made an FSeq editor for the FS1R on Windows.
- Ludo made a Ctrlr panel for FS1R.
- Planet-Groove has a few FS1R patch files for free download. Most are originally from Yamaha.