The Prophet moniker is a legendary one in the world of poly synths, from it's beginnings back with Sequential Circuits in the 1980s up to the more recent Dave Smith Instruments Prophet 08 and Prophet 12.
Tough boots to fill, we know Dave Smith has a pedigree when it comes to designing synths.
The REV 2 is an evolution of the Prophet08 specifically, with broadly speaking the same architecture as the now retired Prophet 08, the REV2 can load the same patches, but just has more features, and now more polyphony (available as 16 and 8 voice variants).
First up, you get the same 2 Osc DCOs, with variable waveshapes - like PWM but for all waves, Sub osc (DCO 1), noise and audio rate mod of the Curtis Low-pass VCF, what is new is the on board FX, single processor per layer (A/B split or layer), polyphonic sequencer, 8 mod matrix slots (up from 4) and sequencer.
These bring the features more in line with the OB6 and Prophet 6 (though they have analog VCOs).
While seemingly not that big a change, the mod options expand the routing exponentially.
We could debate the merits of VCOs vs DCOs, but lets not. The bottom line is that DCOs offer more stability and a tighter degree of control. That and they are lower cost to make and calibrate, so that one of the immediate benefits. To my ears, the DSI DCO's do lack a little in the low end, but it's not going to affect most practical applications in all but the most bass demanding situations. The waves all have quite a wide range of sonic options with the 10 octave tuning range and variable wave shape - no through zero PWM though on the Square wave, though it's tantalisingly close.
One thing I did find was that while you can layer up to 15 voices in unison mode, it's always mono, no option to assign 2 voices per note and play half the polyphony which surprised me.
It's a Curtis filter and gives us a 2/4pole Low-pass self resonant (in 4 pole mode) analog filter. The resonance doesn't remove the bass and provides a pleasant brassy quality with musical harmonics.
2 pole won't self oscillate, and there's no gain staging into the filter or dedicated drive, so the character does remain constant.
DCO1 can be routed to the VCF for some subtle or extreme modulation, most apparent when there's some resonance - lovely bell and overtones available with this. It is essentially a pretty basic filter, but what it does, it does well.
4 LFOs per voice - so in a 16 voice REV2 that's 64 of them! Multiple waves, key and tempo sync, though it is not possible to have a fixed LFO across all voices, the result can get quite messy with all those free running LFOs. Routing is pretty comprehensive and they do go up reasonably high into audio rates. I particularly like the unipolar nature of the square wave - makes pitch mod much easier. Of course four means you rarely run out of options too.
3 (D)ADSR envleopes - (D) being delay, VCF, VCA and an aux ENV which has a dedicated routing and amount knob - you don't need to use up a Mod slot for this. Aux Envelope also loops.
One processor with multiple algorithms per layer - remember REV2 has and A/B configuration and can be thought of as essentially two independent synths - each layer can be routed to it's own set of stereo outputs. The FX are pretty good - think OB6 and you're pretty much there, though the reverb sounds a bit more complex to me, ableit limited to only one reverb type. It's also possible to clock any of the time based FX (Chorus, Phaser, Flanger, Delay) as well as modulate either of the 2 control parameters via numerous sources. Additional Ring Mod, Distortion and resonant High pass Filter also available (also DSP). The FX are OK but not amazing, as with most modern polys, they are an essential part of the sound design process.
Two modes - Poly - up to 64 steps but a maximum of 6 notes poly per step and Gated - more of a modulation feature, though it's entirely possible to route any of the four tracks to OSC pitch - this is where you can get very tweaky, routing to many parameters and with steps running either on each consecutive key press or whilst the key is held down.
Lots of possibilities here for mad routings and complex sounds - remember there is one sequencer per layer.
Shame we can't real-time record or overdub in poly mode, similarly, it's not possible to enter note or parameter values in real-time or directly from the keyboard when using osc pitch as a destination - you must use the parameter/value knobs to enter any values here. Could have made it a little smoother to program.
As with the Arpeggiator and LFOs master tempo can be clock divided in multiple ways. Sequences are stored with the patch.
I do feel more connected to the REV2 than I have with the Prophet 08, I don't know if it does just sound better or maybe a more rewarding experience to play with it, but there is a large range of sounds available to the curious synthesist, As the on board memories show (512 User, 512 preset), you can really get lost in the REV 2, though perhaps not as out there as some synths it's still got a lot of potential. The on-board presets offer a great selection of sounds to get you started.
For live work the REV2 gives enough connectivity - two sets of stereo outputs (one for each layer), assignable pedal/cv in, Sequencer trigger input, MIDI IN OUT THRU - USB for MIDI headphones (no dedicated vol). Perhaps the lack of dedicated program or bank buttons means for swift program changes you'll need external patch changes, but that's common to the 08 too.
Each layer can be addressed via external MIDI so you can use a second keyboard to access the A or B layer, polyphony is divided equally in layer mode, dynamically in split. One thing worth mentioning is that in split mode, any after touch will affect both sides of the split.
They 61 key keybed feels good, aftertouch included (not poly) and the pitch and mod wheels are easily accessed.
A good solid workhorse of a poly with the Dave Smith pedigree worthy to be the 08's successor.