The filters are steep and VERY good. Warm and rich or cold and gritty based on the application.

The effects are actually quite good compared to most other synths on the market. I'm satisfied.

The only drawback is that editing sounds from the front panel is a real pain. You really need a graphic editor. The good news is when I initially opened SoundDiver I was stunned to see the amount of parameters this box has. I can confidently say that the FS1R packs more parameters than any synth ever built. It's scary.

You've heard a lot of talk about the Formant Filters and I can tell you that they are cool. Especially with the ability to sync them the tempo. Be prepared for sleepless nights when tweaking these.

Now for the thrilling part. If you have an X/Y controller you are in for a real suprise. Paractically all the factory patches are pre-configured for X/Y. I hooked up my Korg Z1 and started tapping and dragging my finger across the touch pad and the FS1R produced astonishingly different sounds than the original patch. This reaveals it's flexibilty as virtually all the parameters can be routed to a midi controller. Oh, did I mention sequencing those hand moves?

I can understand why this box has achieved cult status. The reason the FS1R never sold well is because most consumers are illiterate technically and so they buy dumbed-down PCM based romplers. The net result is they sound just like everyone else.

Owners of the FS1R are in a different league. The type of people use this box are those who welcome the challange of creating fresh original sounds that no other synth can quite match. Trust me, the FS1R can literally create any type of sound imaginable. And that is powerfull!!!

Anyway, enough of that. I remember reading someone saying, on this site or elsewhere, that any sound you can imagine can be created with this synth. Well, with the capability to use additive-style harmonic waveforms and formants as ANY OF EIGHT components in an FM algorithm, yeah, the possibilities are there. Add to this a well-implemented digital filter (12/24db LP/HP/BPF/BEF) and those crazy-ass formant sequences (which can be looped, slowed to 10% and or sped up to 500%, reversed, etc.)... not to mention a pretty decent effects section and the best sound quality I've heard on a synth for a while (this side of a Triton, anyway)... my only complaints lie in the implementation of the formant sequences... the ones provided are all well and good, but I wish I didn't need a software editor to make my own. Also, the fact that they can only be applied to one (of up to four) Parts in Performance mode, and one at a time, is kind of lame. To me, the closest equivalent (to those familiar) would be the function generators in E-mu's Morpheus. Now, E-mu gave us two of them - one for each source in a PATCH (equivalent to Yamaha's Part) and this was in the early 90's... so why Yamaha couldn't have been a little more generous with the flexibility of the formant sequences, especially since they're the main feature of the machine, is a mystery to me. But that really is my only complaint...

The unfortunate part is that, while this synth seems to have developed a definite cult-type following, sales were not equivalent to those of more pedestrian synths and they seemed pretty quick to discontinue the unit. So those of us who love the machine may be stuck without any further OS upgrades or possible future editions (I'd be all over an FS2-R if they put one out)...

Oh well, guess we'll just have to live with the quirks of this machine, cos in spite of them, it's still one of the most unique synths ever made. Find one if you can...