EDIT: Thanks all for the help. I decided on a Minifreak after trying out the VST version of it. The ease of tweaking right on the synth, much less menu diving, the sequencing, and the sounds and FX are all great for what I'm looking for. Found an open box of it for $479 and snapped it up.

I have a pretty large eurorack, a Moog Matriarch, and a vintage Juno 60 (that only works about half the time these days, need to get it fixed). I need a small-sized synth to play polyphonically alongside my eurorack that has at least 6 voice polyphony and can give me a wide variety of sounds including warm and wide. I'm not in an area where I can test these in person so I'm trying to make a decision to try to avoid returning/exchanging if possible. (EDIT: Not intended to be a full-on controller for the eurorack, I generally want it to play live/sequence chords polyphonically alongside.)

Key points:

> I want to interface with my eurorack. Hydrasynth Explorer has some better connectivity overall but doesn't have clock in for some weird reason. I could live without the CV and gate outs on the Explorer if I had to , but they'd be great to have.

> I don't mind diving in and programming sounds, but if it's too menu-divey and complicated then it gets tiresome quickly. However, the Minifreak seems limited sonically compared to the Explorer...tho I could be wrong about that.

> Sonically it's very hard to judge without hearing them in person--I want a big range, from thin and gnarly to fat and warm. I'm already covered in the analog department with all my other synths and eurorack, so digital is fine as long as I can also get a wide and warm sound with it. I like both going very deep and also staying simple.

> Important: I can't go too much bigger than either of these.

> Explorer not having a sequencer (stepped LFOs don't count) is a bummer for me, but...

So you can see why I'm torn and why it's so damn hard to decide. If the Minifreak can get as sonically varied as I'd like (doesn't need to be as varied as Hydrasynth, but I do want to be able to get warm and wide as well as dirty and reedy stuff), then that could be the winner but...

Opinions based on what I've outlined? Are there other options? I don't mind full-size keys but again it can't be too much wider than these are. Definitely not the Korg Minologue XD, it's too limited sonically for what I want.

Have you given the MiniFreak V demo a try? Best way to get a sense of what it can do. It's very diverse, just not very deep. Also only the effects are stereo.

Is the synth meant to be a Eurorack controller? Or are you just looking to sync?

I will check that out, thanks, didn't think of it.

It's not meant to be a controller, no, just to sync and so I can play live/sequence polyphonic chordal stuff easily.

When you say warm and wide, the little Modal Cobalt 5s very much hits that character ..., but alas only 5 note polyphony and only sync in / out & no cv. (If I remember correctly). Has an excellent sequencer (step / realtime)

Imo it sounds better than the 2 you mention in the warm/lush dept.

Still a chance Modal might do a Argon 5s & Carbon 5s.

Another question I have is are you keyboard-focused? Two hands on the keys, getting expression out of velocity, aftertouch, wheels, pedals. Or are you more about tweaking parameters on the fly?

Given your other synths and intended goal here I'm guessing the later, which would make MiniFreak a much better choice, because it has a more performative interface with direct access to key parameters, a sequencer, and also a Chord/Scale feature which lets you play chords with one finger, therefore freeing up your hands to do other things. It supports multiple playstyles (and if you don't want to play it it can do some degree of generative stuff too) .

The Hydrasynth is really about diving deep into sound design, that's the one thing it's really good at, which does not seem to be your goal here. Its only noteworthy performative feature is the polyaftertouch keyboard, which is nice and exotic but caters to one specific playstyle.

Anyway, as far as sound goes I think both could satisfy your desire for variety and dirty and reedy stuff but neither will do wide and warm by just filtering a sawtooth and turning on the chorus. That's not the kind of character that they have by default, you'll have to work the oscillators and effects etc a bit more first. I suggest saving some templates so you don't have to do this every time.

btw, for context, I've had a MiniFreak for a few months. I don't have direct experience with the Hydra.

Beware though, if you want to use the chord/Key features of the Minifreak to trigger your modular or other synths it
won´t work.
The chord and scale features only apply to it´s own engine unfortunately.
So you will hear wrong notes out of scale on your external gear when pressing a wrong note.

IMO the Hydra is one of the best synths ever produced .. It's absolutly just stunning !

Gotcha, thank you.

I would mostly be using it on its own in conjunction with my eurorack.

Thanks for this, very helpful. You're right, diving deep into sound design is not my goal here. I would be tweaking parameters on the fly, and playing chords and/or melodies on it.

My understanding is that the Minifreak does stereo through its FX as opposed to the synth engine itself -- is that true?

I could probably get by with 5 voices. The Cobalt 5S looks interesting. Does it have the capability to get weird and grimy, too?

The Cobalt VA engine is a very good one. Particularly the filters. I don't own one (yet), but have watched quite a few videos. It seems to be able to do everything, but particularly excels at warm lush pads and atmospheres. There are tons of vids out there.

The sequencer is very good too, with sophisticated programmable arpeggiator of 32 steps with rest capability and up to 2048 steps before repeating

I did have a Hydrasynth desktop for a while. It sounded very good, but I always felt it didn't have any particular character of its own. The Cobalt seems to oodles of character to my ears.

It also has the excellent Modalapp programming interface which is great as the synth has a tiny LED display.

I decided to go for it because I already have a USB MIDI-to-CV converter in my Eurorack which will take care of that issue. Didn't think of that before for some reason!

Correct. Have fun with your new synth.

btw, in the VST/MiniFreak V there's a tutorial section with some interesting tips that are worth a quick look.