MFB Synth Pro is the newest machine from the Berlin based manufacturer and is a solid, desktop unit which offers a surprising amount of features in a small desktop unit.
It's an 8 voice polyphonic analog synth with the ability to run in various multi-timbral modes as well - with 8 mono synths a possibility.
With 3 VCOs for each of it's 8 voices - twin filters - a 2 pole mult-imode (LP/BP/HP) and a 4 pole Low Pass filter. There are also 2 LFOs and 3 Envelopes, single digital FX plus a 16 step sequencer and Arpeggiator.
The VCOs have a feature I've not come across before - they are switchable between true VCO and DCO modes. This means we can create more "living" multi-oscillator sound or a more stable, digitally controlled set of oscillators. The manual also states that the oscillators are discretely built rather than chip based, which is an astonishing feat considering the size.
Each oscillator features a morph control which starts at a sub square wave, through sawtooth, triangle square, then EXTRA - which is selectable from PW + Ring for oscillators 1+2 and PW and Noise on Osc 3.
They are not what I'd call massive, but plenty warm and full enough for most applications. Additionally, there is Oscillator sync: 2>1 + 3>2, as well as FM 3>1, and 3>2 with a dedicated depth knob.
The twin VCFs can be run in serial or parallel and are also able to be split across the stereo field and blended via the dedicated blend knob.
Both are able to self resonate and have interesting additional parameters as with other MFB filters, the amount of resonance can be dialled in, to further change the character of either. The 4-pole also has Q-compensation for minimizing the loss of bass when resonance is dialled in.
2 LFOs are global rather than per voice, and can be free-running, key reset and 1-shot modes. Multiple waveforms (Saw, Tri, Ramp Up, Square and S+H). They are fairly limited in rate, 200Hz being the maximum. Both can be tempo synced.
3 Envelopes - 2 full ADSR and on A/R all are loopable and can be used at reasonably high speeds, but only one can be looped at a time.
While there are a few routing options, there is no actual mod matrix and destinations are pretty limited. Which is a shame, but does mean you have to search out the sweet spots a little more carefully
A single digital FX generator with Reverb1, Reverb2, Delay and REV/Chorus algorithms. Each has three parameter controls, which for some reason are not labelled descriptively in the LED display, parameters are also not modulation destinations, but will respond to MIDI CC.
As effect go, they are OK, though not spectacular, there are other algorithms mentioned in the manual, but perhaps these have not yet been implemented in firmware.
One thing that is quirky, is that the routing is solely from filter 1, so if you have a stereo width of the filters at 100% then the amount of FX send is also governed by the filter blend.
The Synth Pro has various voice modes: Poly, Poly1+7 (mono voice + 7 poly), Chord + 4 (4 voice poly + chord), Mono (8 mono voies) and Unisono (stack all voices and detune) - these are set globally and unfortunately are not stored with the preset - which is another quirk of the operating system - something you will become used to the more you use this.
Each of these modes sets the synth up in different ways and any change must be followed by the Enter key.
Poly1+7 is two parts, one mono and one 7 voice poly - select the active part to edit the sound., Mono is the same but with up to 8 voices.
It's an interesting way to work but does share common FX. Also each part of each voice must be saved while that part is selected - this is a little fiddly and the fact that you cant name the patches - even though we have a reasonable LCD makes it more arcane.
However you can operate in Multi-timbral mode and that is also a unique feature.
In the firmware I was reviewing (3.7) it was not possible to store the patches under a single user patch, each voice having to be stored and recalled manually, but in 3.8 this has been addressed. With a further 80 presets added which will also bring back the full Mono voice assignments - though you still need to save each patch per part, they will be recalled together. This is certainly an improvement, but I was unable to test this as the unit had been returned by the time it arrived. You still also need to manually assign the voice mode though.
This is just a basic 16 step sequencer with polyphonic capabilities, but no parameter recording sadly, I wasn't especially thrilled by it, but it can be useful - it is possible to play over the notes so for chord sequences and a top line or mono simple sequenced lines it has a purpose, same for the arpeggiator - works fine, but nothing special.
MIDI IN/OUT/THRU on full size connections, USB for OS and patch dump (requires 3rd party USB Driver not mentioned in the manual) and a USB Host mode for direct MIDI controller connection - neat idea, but I had no compatible MIDI controllers to test this.
The audio out is on a stereo 1/4 connection so requires a stereo to 2x mono for connection to most equipment - I can only assume lack of space for this curious choice, plus a 1/8th headphone jack.
Power is a 6v 4A external PSU - don't lose it, I couldn't find anything meeting that spec on Amazon...
I should also add that the USB to computer connection for OS updates requires use of terminal emulation software and transmission of .bin files - as this was not a review unit, I didn't feel confident trying this in case I bricked it.
Once the USB driver was installed, I could also not find any available USB MIDI ports to backup patch data, so this is something that would benefit from some more work.
There is no doubt that a 3 voice analog poly has a certain allure to it and the sounds that Synth Pro can yield can be delicious - especially with one OSC tuned to a fifth, it's yummy!
You do need to find the sweet spots here, as the routing options are limited, but it's got that VCO magic for sure.
I did find some of the OS features a bit "quirky", this is something MFB users may be acclimatized to, but can be a little frustrating - specifically the multi-timbral operation and the USB communication was not implemented well in my opinion.
But, it can sound magnificent and it is certainly compact. I can't think of anything analog on the market with these specifications, but there are more fully featured and less quirky poly synths which have more digital elements of course.
If analog is important to you, and you want 3 VCOs per voice, or you need the multi-timbral features, then this is worth a look.
MFB Synth Pro is £952/€1066 (could not confirm US price)
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