The Moog Sub Phatty was launched at NAMM 2013 and drew a lot of interest as any new Moog synth is likely to. With marketing showing wizened synthesists getting excited about the new circuitry, there clearly is something going on here.
The basic architecture will be familiar to most, two VCO's plus a Square sub Osc, single LFO, two envelopes (ADSR with hold and delay) and the mixer section. We should mention that this is analog circuit stuff with digital control, this seems to be the way things are going, allowing some clever things to be done while retaining the analog signal path. For instance, changing the scaling of the knobs to give a smoother change in certain ranges.
Moog have worked hard to ensure that the oscillators are stable within 30 secs of power up and can remain so throughout. And I can confirm that there was no MiniMoog type drift or plain wrongness!
So firstly, there's a variable waveform for each oscillator which means PWM or just general wave type modulation can be achieved from TRI through SAW to Pulse Width - hooray, I am a fan of this. You can modulate either or both Osc and also use the filter envelope as a modulator.. Additionally there's a noise source, so instantly you have a bit more than the Slim Phatty and the Minitaur. The classic Moog Ladder 4-pole 24dB filter is also present, though with some clever mixer tweaks and the addition of the new Multi-Drive you can really change the flavour of the filter.
You can drive each Osc (1/2, sub and noise) into the filter separately, on a scale of -0 to 12. With levels of 0 to 6 being clean, 6-12 introducing more drive. So you can tame the classic smudge of the Moog filter drive if you wish, or push it a little harder - this one goes up to 12!
Multi-Drive adds additional drive post Filter from an OTA circuit and can range from a hotter signal to molten drive - great for bringing out resonance, wave modulation or Oscillator sync.
Thats a casual sentence but in practice, there's a LOT of tonal variation happening in that single knob that can drastically affect the sound of the synthesizer.
I should mention that the Sub Phatty has a solid metal casing and sturdily mounted knobs giving the impression of something very well built, and indeed that is true, you notice this as soon as you get it out of the box. Build quality is not an issue.
The 2 octave keyboard is velocity sensitive, sadly no aftertouch - and I am not becoming the AT lobbyist, it's just that the Arturia Minibrute has it, as does the Novation Bass Station II - on a mono synth, it really does add expression - just sayin..
There are a number of hidden shift features that can be access via cobinations of memory, bank and front panle switches. For instance, you can dial filter env and amplitude envelope amounts in using these shift functions to give you access to velocity. These functions really do open up a lot of extra synthesis details and are jolly useful if a little tricky to navigate via the front panel (using the editor is best IMHO).
Another neat feature is the ability to use the Filter and Amplitude envelopes in repeat mode, effectively adding another LFO type modulator to the mix, additionally the ability to change the number of filter poles from 24dB to 6dB (4 through 1 pole) slope is another way to quite drastically change the character of the synth.
My only issue is that while many of the important primary synthesis functions are front panel, these shift functions are accessed via various combinations of the 16 memory buttons, and require the manual to recall. To have a seamless journey into synthesis, you would be advised to hook up the free editor/librarian (Mac/Pc standalone or plugin) which allows easier access to the hidden parameters, and also to manage and store larger quantities of patches other than the built-in 16.
Speaking of connectivity, Audio in and output are obviously there, USB and MIDI ports allow connection of external sequencer and modules etc, but there's also CV and Gate - plus CV control of Filter Freq and Amplitude, so you can on a basic level incorporate this into your modular or other analog world, though only as inputs, you can't control other analog gear from it.
Overall, I prefer this to the Slim Phatty and Minitaur, being able to dial in the amount of "Moog-ness" as far as the filter is actually quite useful, the oscillators are beefy enough to give you that thunderous bass and other classic Moog tones, but you can find all that in-between too. Sure, it's a premium product, but Moog is Moog. You pay for what you get. I can see the Sub Phatty being a popular choice amongst Moog first timers but also for more experienced Moog owners, the subtlety (or not) of the drive really gives you a lot more variations in sound.