Oct 1


Are you up for some analog synth sounds – I mean 100% analog? Well I have got my hands on the Moog Slim Phatty which is a single voice 100% Analog subtractive synthesizer. In terms of big names in synthesizers, you do not get any bigger than Moog.

As you probably know, the very last thing Bob Moog worked on was the Little Phatty Synth. Whilst it still had that old Moog classic sound, it had some up to date additions, one of which being USB connectivity. The Legacy he left behind in Synth design has led to the release of a smaller rack-mounted synth module aptly named the Moog Slim Phatty. I am surprised the word ‘Boy’ wasn’t in there somewhere.

The Slim Phatty will sit nicely anywhere in your studio on its four rubber feet or you can purchase ears to rack-mount it. It is very solidly built with a metal casing and as you turn it on it has plenty of status light indicators. If you don’t wish to rack-mount you can also buy wooden end-cheeks for it. Personally, I like it just as it is, so I shall power it up, start to get to grips with the layout and make some awesome sounds.


The layout is almost identical to the Little Phatty keyboard. It has 34 buttons and 7 knobs and you can simply divide this unit into 6 main areas; 1 – The LCD and User interface, 2 – The Modulation Section, 3 – The Oscillators Section, 4 – The Filter Section, 5 – The Envelope Generators and 6 – The Output Section.

There are four very sturdy rotary pots with bright red 15 point LED indicators to show you where you are. Under each of these is a very user friendly editing system, whereby you simply press the desired button and the rotary pot will control that aspect that you wish to edit – brilliant.

The size of the Slim Phatty is 43.2 x 11.6 x 13.5 cm and its weight is a solid 2.6 kg.


In the first section, it has something called Master Mode and there is a Master Mode button which basically takes you into all of the global settings and the Advanced Preset settings for the Slim Phatty. You will also find the routines for the sending and the receiving of data. There are eleven Advanced Preset menus for: Filter Poles, EGR release, Gate Trigger Options, Filter Sensitivity, Additional LFO Modulation Sources for (SRC5 & SRC6), Pitch Bend, Secondary Modulation destinations, Keyboard Priority, Pot Mapping and the Arpeggiator.

Next to this is a preset button for you to select from the 100 Presets. You will find this all very user friendly with the Value dial, the curser button and the Enter / Store button. Under this you have a fine tune button which is very sensitive but can be turned off, a Glide On/Off button and an extensive Down and Up Octave buttons which cover four octaves. I like the usefulness of the LEDs with the octave buttons because they glow red when you go up or down one octave and orange when you go up or down two octaves.

The LCD itself is only a monochrome, backlit 16×2 character display and I found this to be generally OK working in conjunction with user interface. There is a little bit of a learning curve to it, but you soon settle down to knowing its ways.


Another favourite of mine is the Programmable Modulation Matrix. This is where sounds can really come alive and provide you with endless permutations of tonal possibilities. Basically for the Slim Phatty, you can specify a choice from six Modulation Sources and four Destinations and you can also specify the amount of modulation. The Sources to select from are:- LFO Triangle, LFO Square, LFO Sawtooth, LFO Ramp, Filter Envelope / Sample and Hold, and Oscillator 2 / Noise.

The destinations are Filter (which affects the filter cutoff), Pitch (which affects the pitch of both oscillators), Wave (which affects the waveform of both oscillators) and Osc 2 (which affects the pitch of Oscillator 2).

The Modulation Section has four buttons (LFO Rate, Source, Amount and Destination) and a control knob. The control knob controls either the LFO rate or the mod depth. Pressing and holding the ‘Amount’ switch enables the Modulation control knob to act as a Mod wheel control.


There are two identical Oscillators which are continuously variable. I love the way they very smoothly take you through the different waves allowing you to select somewhere between two waveforms to create even more tonal possibilities. There are four waveforms to select from for each Oscillator which are Sawtooth, Pulse, Triangle and Square. Once you have selected your waveforms, the fun really begins where you can choose different parameters for each such as different octaves for them, detune them to fatten the sound further or sync the Oscillators.


The Slim Phatty’s mono filter section has that lovely Moog 24dB/Octave ‘ladder filter’ which is very smooth. It is only a low-pass filter but it can self-resonate. There are further controls so that you can adjust the Cutoff Frequency, Resonance, Keyboard Amount, Envelope Amount and the bit I like here is where it gets mean and dirty by turning up the overload level and really distorting the beast. From this section the sound goes to the output Voltage Controlled Amplifier which is controlled in Section 5 – by the Volume Envelope Generator.


The Slim Phatty has two envelope generators with eight buttons arranged in two banks of four. One bank controls Attack, Decay, Sustain and Release (ADSR) for the amplifier (Volume) and the other controls ADSR for the Filters (to control the cutoff frequency). The Filter envelope generator can also be used as a modulation source through the Modulation Matrix.


There is not much to say here as this is the smallest of the sections with just a Volume knob and an Output On / Off button. The Volume control simultaneously adjusts the level of both the monophonic audio output and a headphone output. The idea behind the Output On / Off button allows you to turn off the main audio output but keep your Headphone signal going.


Listening to the presets on any synth is always an interesting experience. It is very strange to me (and I am sure I have said this before), but if I was a manufacturer of a new Synth and I am desperately trying to sell my product and get the Public to part with their hard – earned cash, then an area that I would pay particular attention to would be the Presets. I would want the person auditioning it to have that ‘Wow’ factor as they played their first sound. This has only happened to me a couple of times. The first was in a music shop where I played two chords (Gm7 and Dm7) on a Yamaha DX7, as I held the Chords down I had the whole shop go quiet and everyone gaze at me as if I had played the best thing they had ever heard and the second was when I first heard the Novation Supernova II. However, it seems today, this doesn’t happen and we all talk of a Synth’s potential rather than what it can do now.

This is not to say that the Phatty’s presets are not good, it is that they do not have that ‘Wow’ factor. The annoying part is that, after using it for a short time, you know what it is capable of and this makes you wonder even more why the presets are not awesome in the first place.
If nothing else it motivates you get editing and come up with something better – which after all is what it is all about.


I must admit that I struggled to find the Arpeggiator in this user-friendly layout; I was expecting an Arp Button on the front panel. However it is not too bad if you are in Preset Mode, as you simply press down on the Value knob. As you do so you will see an ‘A’ on the LCD. You can also latch the Arp by pressing the Enter button and you will then see an ‘L’ on the LCD. If you want to adjust the tempo as you are playing, just turn the Modulation control. If you want a finer adjustment you can use the Value knob. So this is just a matter of getting familiar with this way of working. The other Arp parameters are available in the Advanced Preset Menu. Here you will find that each of your presets can have amongst other parameters, the Arpeggiator enabled and the pattern it uses, (which is either ‘Up’, ‘Down’ or in the ‘order that you play’).You can also decide whether the clock should be internal or sync over USB to the tempo of your DAW. There are seven pages for the Arp so I think it is a shame there was not a dedicated Arp section on the front panel.

I know I have briefly mentioned the Advanced Preset Menu, but this is the heart of the Slim Phatty. What I like about it, is that it has options for you to change the settings for individual presets rather than change the global settings. For example you can select Filter cutoff slopes of 6dB/oct, 12dB/oct, 18dB/oct or 24dB/oct on a ‘per patch’ basis. You can set up alternate tunings for each Patch which is something you will not find on other mono analogue synths.

Something also worth looking at is the Gate menu. Here you can select from three options; Legato On, Legato Off and EGR Reset. With ‘Legato On’ you will find that it will not retrigger the envelope until you have released the key. ‘Legato Off’ on the other hand allows you to retrigger successive notes from the current envelope value rather than at zero (I really like this option), and finally ‘EGR Reset’ will retrigger the envelope with every note you play, regardless of whether you’ve released the previous key.

Again something that is not at all obvious to you is that it also has Performance Mode. This mode (which is great for ‘Live’ use), allows you to create four banks of up to eight presets and you can step through these in order (by turning the Value knob) regardless of where they are in the storage area of the 100 memory patches. I have also just found something called Precision Mode. Apparently here you can carry out precision editing of param¬eters using the value knob. Each parameter stored has a value from 0 to 4095 and this value is shown on the second line on the screen.


Around the back you have the Power supply and On/Off switch. This isn’t particularly good place to have an On/Off switch if you rack-mount it, so you might need to give that some thought. The Power connection is a standard IEC three-prong 120 – 240 Volt AC supply which is far better than a wall-wart. The other good point about the power supply is that you can adjust the voltage to match the country you are in. There is also MIDI In, Out and Thru, Four Control standard jack inputs (KB Gate, Pitch Control Voltage, Filter Control Voltage, Volume Control Voltage) to control the Slim Phatty from other Analog equipment, an Mono Audio input, Mono Audio Output, Headphones and a USB2 connection for midi control over the unit via your DAW. Obviously the Headphone Socket too is not in a good place if you decide to Rack-mount it.


You really get a lot of dirt, grunge and distortion from this module and what you can achieve from its basic arpeggiator is really 2012. I love the way you get some sounds that sound up-to-date in a retro way. It is about the cheapest way you are going to be able to add that classic phat analogue Moog sound to your arsenal of sounds. When you consider you get the same sound engine as the Little Phatty at approximately £400 less, it is a great purchase. It is a shame that Noise is not available as a sound source and I really can’t believe they put the On/Off switch and the headphone socket at the back but the positives really knock the few minor niggles for six.

It is a wicked analogue synth with USB and Control-Voltage inputs. It is fun to play around with, especially the Filter (which has a great range) and the Arpeggiator You get some good factory presets (and Performance Preset Banks) to start you off but this baby is about sound creation in true analogue tradition. It is extremely user-friendly, so there is no excuse for not getting straight in there and creating some dirty provocative sounds that have all that warmth you expect from a quality Moog product. If you are not convinced have a look at this clip from the very talented Richard Devine:-

There is only one place to buy a Moog Slim Phatty Analogue Synth – just click this Orange Banner for a great price and great service:-

Absolute Music

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