Sounds pretty good, but I'm not a fan of the Treble control. At 12 o'clock it sounds sort of like the Big Muff Treble at fully CW But when you put Treble a little lower it starts sounding good. Only tried in front of an amp, though, didn't try FX return.
Construction is pretty solid. I see three TL072, one 7660S charge pump and DIP 16 device that says CD40668MG4, if I read it correctly. Estimate of components: I'd say eleven diodes, 30 caps, 35 Rs and maybe 4 Qs. Nothing mounted on the back of the PCB.
Not sure if this is worth it for DIY. No doubt Robert or aion could fit this in a BB case, but the original can be had for 53 bucks in Europe (prolly about 200$ US by now), so economically speaking I doubt it makes sense for DIY.
surely the Rigel is not a complete clone of the Ceres. It's way smaller and only has one channel. I watched some YT vids some time ago, where people demoed the Rigel, and IIRC somebody said it's a clone of one of the Ceres channels, prolly the high gain channel.
To be fair even with just one channel 3 dual opamps vs 5 quad opamps isn't really adding up. I guess potentially inspired by the ceres if at all would be more accurate.
Appreciate you cracking it open!