Hi, is there anything here missing - something which doesn't fit. I'm looking for wavetable synth with powerful melody shaping possibilities, able to work with external sound sources but also generate sounds from the rack.

Yes. Lots.

There are no filters. You have only one envelope generator. There are no VCAs. There are no LFOs or utilities. How do you intend on mixing your two different wavetable modules?

The Metropolis can output quantized scales and MIDI from an external source will also be quantized, so why the big Instruo? I don't have a problem with the RainMaker, but it's basically the only thing that'd you find accessible plugging in an external sound source.

Don't take it the wrong way. But I think you've put together a rack without the knowledge of how modular synthesis works. If you were to buy all of these modules, you will spend a lot of money and not get very much use out of it. At this point, you'd be better off buying a copy of Serum and staying inside of the DAW.

I'm in agreement with Ronin here...this build is all but useless. There's so much stuff missing that would be essential to a modular's operation that I can't even tell exactly where this build is going.

You need to back waaaaay up and study how synthesis works...not just modular, but in general. This build has audio sources...and then it's missing everything forward from that that should be in the audio signal path until you get to the Rainmaker and Audio I/O. The sole modulation source is the Black VC EG...but without filters, VCAs, and so on, that's pretty much useless unless you want to modulate the oscillators to make funny noises. In short, it'll be a rather expensive and unsatisfying not-really-an-instrument.

If you insist on going with modular, you need to understand how it works before doing the musical equivalent of tossing $3k into your fireplace. My suggestion would be to stop messing with MG for a while, and instead get a copy of VCV Rack (https://vcvrack.com/). It's free, it functions more or less identically to a Eurorack system, and it has a very extensive module set. Learn what does what, how, and why...and also why the UNsexy modules in a build are sometimes more important (when taken as a whole) than those really superduper ones with the blinkenlights and twistenknobs. And if you insist on spending money on a physical device, start with a patchable synth that has most of the building blocks you need built in so that you have a proper device to learn on.

This is a problem that actually crops up on here a lot, btw. Right now, you have a lot of people running around going bonkers over modular synths, thinking they're the new essential (sort of like the hysteria over the Roland TB-303 in the mid-90s)...but the fact is that unless you have some real sonic ideas and goals in mind that you know require something other than a bespoke instrument, and unless you also know the tech that makes those ideas and goals possible by having learned them either via a good text on the subject, various software tools like VCV Rack, or hardware that's already taken care of the module selection process, the end result will usually be a lot of money spent on an unworkable system.

I agree. Some serious study in VCV rack would go a long way.

But if the OP is dead-set on getting into Eurorack ASAP... I would recommend a preconfigured system if you have money burning a hole in your pocket.

Several manufacturers like Roland, Pittsburgh Modular, Make Noise, Erica Synths, Doepfer, etc. provide this.

Dealers like Perfect Circuit also offer their own in-house pre-configured systems. The median price is around $2000US. This isn't a bad entry point if you really just want to start wiggling knobs and learn-as-you-go.

Another and much cheaper alternative would be a semi-modular synth (as inexpensive as $300)... and a small skiff for external modules to be populated after you have a handle on the semi-modular.

Each solution has strengths and weaknesses and I'm not advocating any of them as being the best way to go. But they are better than your current plans.

Thank you all for constructive feedback. I will take a step back. Most likely return for further advice. BR