Review: Moog DFAM

 

I thought I’d never get a Moog synthesizer.

Yes, we all know how Moog had revolutionized the synthesizer world by releasing, with the Minimoog, the first keyboard synthesizer. Yet what they have to offer today often seemed to me as lacking innovation, but not in high prices. I was missing an innovative product at a competitive price.

Yet when I read about (and listened to demos of) the new DFAM semi-modular synth, that changed. Price: well within the ballpark of comparable semi-modular synths. Innovation: at least it didn’t look like a cross between a decade-old synth with some innovations from other folks. I decided to get it.

Introduction

Arriving in a nice cardboard box, you get the DFAM, a power supply (with interchangeable plugs – looks like there’s a chance to loose them), a manual (here, individual copies in English and German – bonus points), a set of six patch cables in colours from black to light grey, and a bunch of overlay sheets both blank and with some presets.

The thing quickly connects to the wall and to a pair of headphones through the rear-side 6.35mm out. And then you’re all set: the thing contains, next to the actual synth, also a sequencer, so you can start playing. No firmware update, no USB – no MIDI even; this thing is eurorack connection standard and eurorack connection standard only.

Before we dive any deeper, here’s a word of warning: if you’re looking for a thing for all your standard drum machine needs, this one will completely disappoint you. There’s other things available for you. If, however, you’re still curious – dive into the details with me!

Architecture

So what do you get? As a short overview:

• Two VCOs with selectable triangle and square, VCO2 offers hardsync and a hardwired VCO1-VCO2 FM.
• Three AD envelopes, two of them (VCO and VCF) with a snappy attack and adjustable decay, the third (VCA) one allows you to select “slow” or “fast” attack in addition to the adjustable decay.
• A switchable HP/LP filter (4-pole transistor ladder design).
• A 2×8 analogue sequencer.
• A noise source which feeds the third in of the 3-channel mixer,
• and 24 patch connectors.

All in all, this set of components looks like a combo that can recreate all standard analogue sound things you might want to do, and then some. On the other hand, you obviously can only create one sound, and you only get eight steps, which puts it at a disadvantage in comparison to about any analogue drum machine there is (and don’t even mention the digital ones).

Getting into it

Moog has however included a few tricks that are not visible at first sight. Perhaps the most powerful one is the sequencer which can, as the manual briefly mentions, also reach well into the audio range. Say again? You set one VCO to a square, connect its output to the sequencer’s clock, and finally one of the sequencer’s (“CV”) outputs to the external audio in, and got yourself an arbitrary waveform generator. Individual adjustable rise/fall times? Use the sequencer’s second track and connect it to said VCO’s CV in to modulate it. Wicked!

Of course, as with most modular thingies, the inputs are rather high-ohmic, which means that you can also clock the sequencer with your finger for some quasi-aleatoric drum patterns. Combine that with the trick described above, and you got your own John Cage tom solo.

Going through the individual sections one at a time:

Oscillators

Both oscillators offer a frequency control, a switch between triangle and square, a mixer knob and a VCO EG amount (+/-). There’s a decay knob for the VCO EG (attack is always “snappy”), a FM knob (to adjust FM going from VCO1 to VCO2) and a hardsync switch for VCO2. The sequencer’s “pitch” track can also be routed to VCO2, both VCOs or no VCO at all (for routing it to VCO1 only, you simply use the patchbay).

Considering that the frequency range for the VCOs is roughly ten octaves, having them on one knob (even a big one) is a little tricky if you want to go “tuned percussion”. While this is still acceptable for the big and sturdy knobs for the VCO frequency (and all settings with the exception of the mixer and the sequencer), it’s even more tricky for the sequencer, where if you want to play “tonal” stuff, everything is really apparently the same visually – but I digress.

Both oscillators give you what you’d expect, but already here we arrive at one “trick up the sleeve”: there’s a FM amount input jack in the patchbay, which you can patch to any source, e.g. an envelope, and this way arrive at those cymbal bell strike-kinda sounds in the attack phase – a feat not often seen with analogue synths.

Even though Moog is quick to point out that those analogue things aren’t really that stable, reproducible and identical, once you overcome the issue with setting the knobs correctly, both oscillators appear to stay in tune with each other also for the duration of a prolonged noodling session.

The oscillator section gets completed by a noise source (without parameters) that shares its mixer input with the external in.

Filter

The addition of a highpass option is a welcome addition first and foremost. The filter sings well but very musically/cleanly when driven into resonance. However, it almost appears as if it was a gain-normalized design, as if you start to bring up the resonance in LP mode, all of the low frequencies seem to vanish even before oscillation sets in., giving it more of a band-passy character. While this might be pretty ok for a cutting acid sequencer voice, I consider this a problem for heavy analogue synth bassdrum booms, and for that reason haven’t really touched the resonance knob that much.

At mid resonance and cutoff settings, the LF attenuation is around 18dB!

Maybe that’s also the reason for another thing that at first appeared as a major oversight to me, and that is that there’s no option to modulate the resonance (i.e. no dedicated jack for this).

Of course, the filter also has its envelope with fixed, snappy attack, a bipolar EG amount knob, and a VCF mod knob (normalled to the noise source/external in).

All in all, the filter really leaves a mixed aftertaste. With the resonance issue, this essentially means that bass drum sounds and resonance don’t go together. On the other hand, the highpass sounds extremely nice (and even having one is a cool thing), and while the aforementioned LP behaviour might be bad for low drums (for which you won’t need resonance anyway), its bandpass-like characteristic gives it yet another direction to take.

Sequencer

Two rows of eight small knobs each for setting the value, with a red LED in between to show position. There’s a big tempo knob and buttons for run/stop, advance and trigger – and also a trigger output and inputs for tempo and the three buttons.

As already mentioned, this can be considered the center of creativity in this synth – but also the part with the biggest limitations at first sight: we’ve simply come to expect a sequencer to have (at least) 16 steps, and competing offers in the modular and cheap-analogue market (Doepfer Dark Time, Korg SQ1) tend to offer a choice between 1×16 and 2×8. True, by using one track to modulate tempo, you can do whole measures (or more) as long as the number of notes does not exceed eight, but with that, your options to sync with something else quickly reach a limit. Add to that the lack of an LFO (which otherwise really wouldn’t be missed), and you have a hard time to generate lively grooves without twisting knobs all the time (or connecting it to a Dark Time or similar, but then why do we have a sequencer in the first place?)

Even with that said, it’s simply a situation where you just have to accept that this thing is “different”, and are rewarded with a lot of funny possibilities that not a lot of other sequencers have – like the arbitrary waveform generator.

Leaving all the discussed things aside, the sequencer works pretty well unless you try to set up a melody on your first try (maybe use an attenuator for that?)

The end result on the sequencer for me is really that, once you accept that it’s not your TR808, you will have a lot of fun working with this thing. A welcome addition to the (eurorack) synth world!

Mixer and VCA

The mixer is a pretty simple affair: three channels (VCO1, VCO2 and noise), with the option to patch an external (or internal) signal into the external source.

The VCA has velocity, which is a cool thing for such an oldskool synth, which also comes with its own input. An option I would have liked (to avoid having to connect an external constant source) is to set velocity to constant in those cases where you use the sequencer’s velocity track for something else, though.

The VCAs envelope is the only one which allows adjusting the attack with a two-position switch, i.e. “slow” and “fast”. This gives you the two typical drum/percussion attacks of drum and cymbal, but nothing in between.

Patchbay

A semi-modular synth would hardly be semi-modular without its patchbay. Moog has added all of the jacks on the right side filling the complete height of the device to give you 24 jacks, with nine outputs and 15 inputs. Interestingly, Moog chose the middle ground in the documentation between Make Noise’s “whatever you patch, it can’t hurt the device” and Dreadbox’ “if you mispatch, your synth may blow” by simply stating nothing on the matter.

There’s a distinction between ins and outs in the lettering with the outs having inverse typeset, but apart from that, no further indication (i.e. if the provided or expected signal is of gate/audio/CV nature).

There’s a lot of very welcome choices, such as the aforementioned FM amount, and also CV control for noise level, as well as for all of the envelope decays. With those things, it’s mostly that you miss something, and for me that would be filter resonance. But then, that would’ve required a full new row of jacks…

What’s Missing

It’s always hard to find something that is missing for a (semi-)modular thing, because you can damn well get your module for that.

Still, a surprise, in comparison to today’s semi-modular competition, is the lack of MIDI connectivity: from Make Noise over Pittsburgh, Dreadbox and on to Moog’s own Mother, they all have it.

Summary

I’d call it a unique and original synth which, while it has some small shortcomings, most of which can be worked around, makes up for it with some unique selling propositions and a workflow that inspires creativity.

If I could have one thing changed, it’s the filter characteristic. Not being able to have one oscillator generate bass drum beats while the filter sings on top without having to adjust volume/gain all the time really reduces at least this possibility. And while we’re at it, I’d also like to have a jack for resonance CV.

The lack of some features, such as MIDI connectivity and maybe a LFO, can be worked around easily by adding those from your Eurorack. That’s the idea behind it.

On the other hand, we have the option for an arbitrary waveform generator, which turns this kinda-drum-thing into a very original analogue, one-of-a-kind oscillator.

I’d call the general sound character well-rounded – which means it will usually not bite, but it will gently but very definitely push.

All in all – maybe not something you need, but a very welcome addition. If you consider my multiple warnings that you will be disappointed if you want an analogue drum machine.

Post Scriptum

Connecting the DFAM to a 0-Coast, a Doepfer Beauty Case, a Minibrute, two effects and having a bunch of patch cables at hand is fun!