Any opinions on the Zadar as a main Envelope generator and Sewastopol II as a main audio I/O and FX send loop interface?
Both look really nice and the Batumi I have I really like.
I have the Zadar, it is best to use as a more complex modulation source then a main envelope,
if you need an adsr for amp or filter, this is not really the field where this one shines...
Hope this helps
I actually think the Zadar is fine as a main ADSR, especially after the firmware update to 2.0 that lets you set a sustain point (so it is useable as ADSR rather than just AR). It is not the most immediately playable module though, and it does require some menu diving to use. But once you get into the menus, it has some fun envelopes that are difficult to generate otherwise, and it is very flexible (e.g., it lets you adjust envelope level which can be very useful, and which is not common for envelope generators).
Sewastopol II is fine as an I/O interface. The input has enormous gain, and it is really shines when amplifying very weak signals. E.g., when sending a passive electric bass into it, I only turn the input gain to 2-3 (out of 10). For line-level signals, the input gain is set well below 1, which can be a bit fiddly to dial in. The output gain is also solid, and I use it regularly to drive full-size headphones (this is not a documented feature, so YMMV). Third, it is an expensive and full-featured module, with a complex envelope follower and gate extractor. If you need that, it is great. If all you want to do is to send line-level signals in and out of you modular, something simpler may be easier to work with. One simpler module is Veils by Mutable Instruments. It is a 4x VCA with sufficient gain to bring line-level to modular level. Another module that many people recommend for line-level I/O duty (but that I have never used) is the Gozinta.
I hope this helps,
If rackspace isn't a consideration, you'll probably be better off with a Doepfer quad A-143-2 ADSR or the equivalent.
The price is less than the Zadar. The Zadar also has an expansion unit that just came out. I'm not sure of the name. I wouldn't undervalue the immediacy of having a traditional ADSR at hand. Having to menu dive the Zadar might impinge on your workflow. ADSRs aren't typically set-n-forget and I'm always tweaking them to get to the magical sweet-spot. It all comes down to you and what works best for you. It wouldn't work for me. But I'd love a Zadar to expand my capabilities.