FM synths have always had the same problem. Everybody loves the sound and nobody wants to program the thing, so most of the FM you have ever heard was a factory preset nobody dared to touch. Audio Damage clearly got sick of that, because Sandbender is their attempt to make FM fun to actually play with.
Under the hood it is a four operator FM engine with ten factory algorithms, plus an algorithm designer that lets you draw your own routing. Every operator gets its own wave shaper that morphs from triangle through sine to pulse, and there is a wavefolder on top for extra harmonics. Then a sub oscillator and six noise flavors, White, Pink, Velvet, Digital, Crackle and Metal, all running through eleven filter types and a modeled low pass gate. That gate is the secret weapon for me. It ties brightness to loudness, so notes get that woody Buchla style pluck instead of the usual polite FM ping.
Programming is drag and drop. Grab a source off the rail, two ADSRs, two LFOs, a couple of function generators, a 16 step sequencer, four macros, MPE, and drop it on pretty much any knob. If you would rather not program at all, the GENETICS page breeds new patches out of whatever you are playing, growing a family tree of variants you can click through. The PERFORM page gives you two nodes to shove around the screen, and you can record your gestures into a loop of one to eight bars. There are 260 presets in the box across nine categories to start from.
For industrial ears, this one is a proper toy. The wavefolder plus the Crackle and Metal noise types can get genuinely filthy, and the low pass gate makes short percussive hits sound like something being struck rather than switched on. Run a drum loop through your head while the sequencer chews on a detuned FM bass and you will see what I mean.
One honest note. This is not a DX7 clone and it does not pretend to be one. The classic FM bells are in there, but the presets lean weirder and more West Coast than vintage. Also the free demo is fully functional but limited to 20 minute sessions with saving switched off, so give yourself a proper afternoon with it before deciding.
Price is $99 on desktop, and it is half price with the code BFCM2026 until December 1. There is an iOS version on the App Store too. Same as the rest of the Audio Damage catalog, it is a perpetual license with no DRM, no subscription and no dongle. Grab it here: https://www.audiodamage.com/collections/instruments/products/sandbender