Dreadbox Erebus is fantastic for bass, though it can do a lot more than just bass. I wholeheardedly recommend one, you can find a V2 for cheap used these days and they sound fantastic to my ear.
Moog Grandmother to me is also great and sounds like one of the best mono synths on the current market, also doing way more than bass. I‘m contemplating getting one, though not for bass duties.
Exactly … but to sound “brassy” a Moog Model-D or its clones would be not my first choice. The OP mentioned Model-D (Moog) and Nyborg (SEM inspired filter) … the SEMs are particularly renowned to generate brassy sounds, even if compared to other 12 dB filter 
Dreadboxes seem to generate great basses in general. I can confirm that for the Nyx too and the Dreadboxes seem to have a particular Greek - grit, which I love, because it brings something new and different to the sound palette.
The SE-02 produces enormous amounts of bass. With three oscillators, cross mod stuff, a delay, patch memory, sequencer etc, it’s a great little package if you can live with the tiny knobs.
But the SE-02 drops the low end significantly, if the resonance is raised. See Nick Batt’s review at 9:00.
It’s a Moog-filter type, after all and it seems to have no compensation
The other question is if you really need high resonance for bass sounds…
Minimoog is famous for its bass, despite this behaviour
Of course, same as a Minimoog, one of the most popular synths for bass that there has ever been.
I know the OP raised that and I did mention that when I first suggested it, just wanted to point out that it does not prevent the synth from producing enormous amounts of bass in most situations.
The SE-02 fits the OP’s “massive” requirement to a tee. It’s a huge sound. The B*hringer D will do very similar things but has no patch memory, sequencer or effects.
Absolutely … we have only to be careful to spice up the sound with the resonance too much, which is a little limitation IMO and it’s not very versatile. But I too love this deep juicy Moog Bass …
I consider since some weeks to get a Minitaur for standard bass duties and to relieve my other synths for other tasks. The demos have been very convincing and I had the impression that some reviews pointed out that the Minitaur has bass-optimized circuits.
Some mono comparison.
I did the same song for all 3 synths Fusebox, then Treadstone then Nyborg 24, I think if I was doing it again I would have used a longer release on the Fusebox version, but it gives an idea of the sounds of the different synths:
Totally agree, the Nyx produces unpredictable and unexpected results everytime. Truely inspirational…
I suppose your Polymath with four VCOs would also be great at basses
I have Minitaur and I’m pretty sure that it have typical moog filter that loose some bottom when Q is increased.
Hahaha, I am not that close to decide, I have been listening more demos for sure… Unfortunately there are not many places I could test synths here, so I guess I will have to trust the demos.
I have no price range in mind at the moment, but the least expensive the better of course…
I found this review series of the Nyborg by Marc Doty that is super in depth and I gotta say, this synth sounds really lovely…
Ps. I checked there is Dreadbox Hades that is also a bass synth but Dreadbox owner said it is basically a simpler Erebus.
That’s a lot of oscillators for sure. Are there any special modes for them (other than sync or ring mode) ? My reference here is the shruti, with its crazy osc modes.
The Nyborg 12 is the telemark without the modulations options, sounds really great, good for percussion also:
All synth sounds in this one are Telemark, so the Nyborg 12 will sound identical:
I’m messing about in the shed at the moment and have a massive percussion loop going with all the synths synced and sequenced, nyborgs are great for percussion, so easy to do.
You don’t have to go analog. I have the Minitaur and Subsequent37, but what I’m warming to now is using my old Nord Lead 4Rack as a Bass mono synth. My Minitaur was bricking (crappy editor) and the Subsequent37 to me isn’t really a bass players bass synth; it’s more baritone.
So, Nord Lead 4Rack to the rescue.
Consider that it’s 4 part multi timbral so you can use 4 different filters at once… well, 4 synths at once, each one set to unison. And the filter modes are 12, 24, 48, minimoog, TB303, BP and HP. The Minitaur doesn’t even come close to it.
It’s about the same price as an AS Nyborg.
Did anyone suggest a Waldorf Rocket?
Many of the synths I would have suggested were instant nogos with the no keyboard qualifier.
Immediate interface and a multimode filter with audio input in a small box without keys.
I‘ve got a Nyx also, fantastic synth! I love that one for pads and Blade Runner-y spheres 
Hey nothing really special about osc modes. There’s a bit reduction effect but it’s kinda meh…
I think where the dom club really shines is it’s sweepable wave forms and filters, cut-off/resonance/contour all sound freakin fantastic . When you combine that with it’s snappy envelopes you can get these nice squelchy 303esque tones.
The Fusebox is worth a look also, a bit more expensive, but loads of cool features. Did this video tonight, just tweaked and played about with the sound so all made up as I went along:
