Five12 Vector Sequencer and Jack Expander - Review


The Five12 brand is already known to many Mac users through the Numerology sequencing application.  Jim Coker is the man behind the brand and he has achieved a solid reputation for support and innovation.  The development of Numerology can be seen as the foundation for the Vector Sequencer and Jack Expander which mark the company's first releases within the Eurorack market.   

If you want to take advantage of the immediacy and sound control of Eurorack, maintain a high level of control over composition and also integrate your fixed architecture hardware and DAW, then the Vector may be the right choice for you.   

I have compiled a number of HOW TO documents covering features and capabilities of the Vector Sequencer.  You can see the complete list of available items here.  These explore many of the features mentioned within this high level review.  

INs and OUTs 

The Vector hardware set, which are purchased separately, includes the Vector sequencer and Jack Expander.  Both provide a high level of flexibility regarding INs and OUTs.  Bracketed numbers below detail the jack quantity for the listed connector type. 

The Vector Sequencer

  • USB - Host: control device like a Computer DAW or iOS device (1) 
  • USB - Device.  Take input from a USB MIDI control device or send MIDI information to an external MIDI keyboard. (1) 
  • Run In / Out (1) send or receive.  
  • Clock In / Out (1) send or receive.  
  • Reset In / Out (1) send or receive.  
  • Mod 1 and Mod 2 inputs (2) 0 to 5V mapping for external modulation sources. 
  • Pitch, Gate, Velocity (Outs) for Part 1 and 2 (2 sets x 3 jacks = 6 total) 
  • MIDI Input and Output (2) 3.5mm jacks and adapters.  

The Jack Expander

  • Pitch, Gate, Velocity (Outs) for Part 3 through 6 (4 sets x 3 jacks = 12) 
  • Trigger Outs (8)  
  • MIDI IN (1) 5 pin 
  • MIDI OUT (1) 5 pin 
  • MIDI SYNC IN (1) 5 pin 
  • MIDI SYNC Out (1) 5 pin 


Vector 3.5mm TRS MIDI IN and OUT jacks are Type B and present as listed below.  This means that if you were pairing it with another Type B device, you can just use a standard 3.5 mm TRS cable to connect the two together.

  • Tip = MIDI DIN pin 4 
  • Ring = MIDI DIN pin 5 
  • Sleeve = MIDI DIN pin 2 (shield)

Module Connectivity 

The Jack Expander connects to the Vector via a pair of rear connected ribbon cables. The expansion cables are just long enough to place the Expander even with the left edge of the Vector in the rack above the master module. A little more give on the connecting cable would have been nice (maybe 3 to 5cm extra), but it reaches adequately.  

Something I didn’t notice initially was that a single pin on each cable has been intentionally removed. The purpose of this is to make it far less likely that you will connect the ribbon cables the wrong way around. This frightened my initially because I thought I had damaged the cable myself!

The Jack Expander is powered by the Vector, thus both devices require only one power header within your case. You don’t need the Jack Expander to get going because the Vector has outputs of all kinds on board.  However, if you have a higher quantity of modules, it is good to have the full range offered by the paired devices. This is especially the case if you want to use the new Drum and Custom Chord Voices, which are a recent addition to the Vector.      

The User Interface

A lot of thought has been put into the User Interface of the Vector and it shows sensitivity to how the user will want to achieve musical objectives.  Jim plays live using the Vector and this experience, as well as feedback from the growing user community, has helped refine workflow and features. The dual OLED screens are clear, and even with my aging eye sight, I can usually tell what is going on. 

It would take a few thousand more words to explain how the UI works in detail so I will leave that to the manual and your own investigation. As the user community has increased and more feedback has been provided, Jim has been busy implementing changes to improve on an already solid start. 
It is a simple process to name your PARTS (explained below) and I chose to name them after the devices I most often connect to the sequencer.  In the above photograph, I have named six parts for Eurorack modules. The final two are MIDI connected synthesizers.  

Screens, Dials, Buttons

When creating or modifying a sequence, the screens will show each step in a row of eight (four per screen horizontally).  Eight continuous encoders sit underneath the screens and are used to control whichever option is referenced on the screen.  A ninth encoder, located to the left of the OLED screens, is used for global and other special functions.  Scrolling through sequence steps in increments of 8 is achieved by pressing the Previous and Next keys.  

Thirteen white and grey buttons (directly under the encoders) provide a chromatic keyboard from C to C.  The button keys are fine for programming sequences, but you aren't going to rock out any Stevie Wonder grooves.  Another five buttons allow access to various menu items and all labeling is clear.  The appearance of the unit is extremely well-finished and build quality is solid.  You are going to find yourself dialing the encoders a fair bit, so remember that hitting SHIFT and dialing will often speed up the process and save wear on the buttons.  

Learning the Interface 

Getting a sequence keyed in and messing with it on the fly is really easy.  However, to learn how to assign chord voices, set up external modulation, assign chance operators (and so on), you are going to want to read the manual and practice the workflows.  There IS a learning curve, but it is a FUN learning curve and wont stop you from generating sequences almost immediately.   

The Top Row

The most often used configuration options are accessed via the top row of buttons.  Most of the buttons provide multiple functions which increment with each press. 

  • RUN: (1) Take a guess what this does. (2) A second press does the opposite of what you guessed for the first press. 
  • RECORD: (1) Enter sequence notes step by step. You can enter notes via the on board keys or an external device. No second function.  
  • PITCH: (1) Step based representation of the notes in your sequence.  (2) Glide configuration per note.  
  • GATE/GROOVE: (1) Step based gates per note. (2) Groove offset per note. 
  • VELOCITY: (1) Velocity per note. (2 - 4) MIDI CC Options per step for CC1, CC2, CC3
  • STEP LEN: (1) Allows some very neat multipliers of dividers per step from positive 1 to 4 and divisions down to 1/8th. This is super powerful!  (2) Repeat options per step.  
  • RATCHET: (1) Enforce ratchets per step from 2 to 4 iterations. No second function.
  • CHANCE: (1) Chance Type per step.  (2) Chance Probability and (3) Chance Bar.  
  • MODULATION: (1,2,3,4) MOD Sub Sequence 1 and 2, as well as configuration pages. (5) MOD External CV IN configuration 
  • CONTROL: (1) Sequence Control. No second function. 
  • PRESET/SCENE: (1) Preset view and (2) Scene view

Minimum Viable Process

To get started, you absolutely need to learn the REC, PITCH, GATE and CONTROL pages accessed via named buttons from the top row.  You will also need to learn ROUTING to connect PARTS to your devices.

Digging a little deeper will enable generative and probability based contols which trigger all kinds of interesting variables.  You can also set the Vector up to respond to external modulation so it can receive signals from that Maths module people keep PMing you about.  Seriously, what is with that? 

I find myself in the CONTROL screen a lot.  This menu really helps take a simple sequence to a whole other level.  I love getting a PRESET running and then messing with the Start and Length settings, as well as the direction and octave of the sequence. So easy, but so much fun!

Generate and Evolve

If you are scared your cat is going to get bored of your repetitive melodies, and move down the road to spend more time with that nice jazz guitarist (who never seems to play the same thing twice), then the Vector may save your strained relationship. There is a generate function which enables the Vector to write music for you.  You can set this function to a specific scale, rhythmic value, and style. Once you have a phrase you like, you can also evolve it with three levels of intensity.  

But don't tell your cat!  He (or she) might not need you any more after seeing how easy it is!

The Manual

To explain all of the capabilities the Vector offers would be extremely time consuming.  So if you are keen to know more, then check out the following resources:

Current Manual 

Sequencing: Heirachy and Main Elements

To operate the Vector efficiently you must remember this:

  • PROJECTS are a collection of PRESETS in a work space (song, live set, etc). 
  • 8 PARTS are present within each PROJECT and are used to route sequences (PRESETS) to connected devices.   
  • PRESETS are sequences which are hosted within a part.  You can have up to 20 PRESETS in a part, depending upon how long they are.
  • Two sub modulations can be applied per PRESET. 
  • SCENES allow you to arrange and switch between multiple PRESETS within a PART easily.  
  • PLAYLISTS allow you to arrange execution of PRESETS in a predetermined series (similar to a song mode).

Summary: PRESET sequences are output through a PART (Pitch, Gate, Velocity, MIDI) to connected external devices.  All your PRESETS, SCENES, PLAYLISTS, etc are saved within a PROJECT. Sub sequences may be applied to PRESETS. PROJECTS are saved to internal storage. 

The Vector ships with an 8GB Micro SD card which is installed to the back of the module.   Because you are saving only data and no audio, 8GB of storage should be plenty.  


PROJECTS are your complete workspace on the sequencer.  When you save a project, you save everything that is currently configured in the running memory.  It is easy to back your PROJECTS up via the USB to HOST mode.


  • A PART represents a possible connection to a target device; usually a eurorack module, fixed architecture synth, drum machine, etc.  
  • You can sequence eight connected devices simultaneously via the available PARTS (and more via Triggers which are described later).
  • Each PART may be associated with CV (Pitch, Gate and Velocity) or MIDI Channel outputs (5 pin or USB).
  • PART types include Mono, Chord (root and interval, preset chords and Custom Chords), and Drum voices (new in firmware 1.4).
  • Chord and Drum types are available on parts 5 to 8, and you can have multiple instances of each type. 
  • PARTS which send multiple notes (like chords or drum types) are output via MIDI or multiple CV outs (1 set per voice).
  • This means that you can play a Chord or Drum Part via one MIDI connected device, or multiple CV connected devices.  


  • PRESETS are sequenced arrangements which may be between 1 and 64 steps in length.  
  • PRESETS allow you to configure a broad range of capabilities, the most basic being gates, pitch, velocity, key and rhythmic operations.
  • You may have multiple PRESETS per PART.  They are designated as A01, A02, A03, etc. and you can switch between active PRESETS. 

Sub Sequences  

Once you have a PRESET sequence written you can play with Sub Sequences.  These are for CV routed PARTS only and allow you to define up to eight steps of conditional modulation.  Eight steps doesn't sound like many, but keep in mind that you could have your Preset note division as 1/16th, and set your Sub Sequence rate at anywhere from 1/16th to 32 whole notes, which means that your Sub Sequence can have a long duration encompassing many sequence repeats.

Whatever you choose, the Sub Sequence will step through and apply modulation for settings including Transposition, Octave, Rate, Direction, and Start. When I started using the Vector, I kind of ignored the Sub Sequences, but now that I have my head around them, they are regularly used and musically relevant - and also simple and fun.  

You can have two Sub Sequences running simultaneously.  For example, one might change an octave UP every 4 whole notes, and another may execute a transposition up a perfect 5th every 8 whole notes.  Sub Sequences are cumulative which can get very interesting!


Eight trigger outs are provided on the Jack Expander. The timing configuration of triggers is applied on a per output basis, via the eight main encoders.  Triggers can also be used in sets of four to send signals for Drum or Custom Chord Parts within your Vector.  More on that later.  A common use might be to have a melody going then trigger a filter sweep every whole note.  

Chance Operators

Anyone familiar with Chance Operators on other devices won't be disappointed by the Vector. Chance Operators include Mutes, Jumps (forces play to move to a step number X before or after the current step), Skip, Velocity changes, Gate status, Ratcheting, Pitch variation, and Jump to a specific step.  Probability based pitch modification (to a chosen interval) is a lot of fun, and can take a short melodic sequence and make it far more lively.

Drum voices also have a few really nice Chance Operators specifically built for drum performance and include things like MUTE on this step (with X% probability) voices 2 and 3 (but play 1 and 4 if notes are present).  This is SUPER cool in practice and a great way of working around the fact that a Drum voice is four signals within a single Part.  See the manual for more information.  

Scenes and Playlists 

  • You can switch PRESETS across multiple PARTS on the fly using the SCENES mode.
  • Example: you might have various PRESETS configured that gradually introduce variations.
  • You can use the SCENES mode to configure each arrangement of PRESETS, then switch between them with ease. 
  • You can use PLAYLISTS to link PRESETS and create very long sequences or song performances.  

Keys and Control  

You may configure MIDI channel INs to route to each PART.  This enables you to program sequenced notes from an external MIDI controller or play THRU to your connected device.  You may also use the Vector keyboard to play connected devices or program sequences.  You must have the clock source set as INTERNAL to play notes THRU the Vector or via the face mounted keys. I usually use the on-board keys to program step sequences and a connected Keystep if I want to use extended pitch ranges.  The vector provides power to USB compliant devices.  

The only limitation to playing MIDI THRU the Vector to is that you must select the associated Part, go to REC mode and select the controller input (CV, MIDI, USB), and then assign it as THRU. This means it isn’t quite as simple as it may have been to switch targets on the fly.

The Dashboard

The dashboard provides the ability to make changes to multiple parts really easily by allowing you to button-press your way to an attribute (for example, sequence direction) and edit it for multiple parts at once.  You can affect Direction, Start, Length, Reset, Rate, Mode, Octave, Transpose, Gate Scale, Velocity Scale, and Chance Scale from the same menu.  This means you can fluidly make wide ranging and simultaneous changes to parts on the fly.  

New Features for the Vector in Firmware 1.4

Drum Voices 

Drum and Chord PART types are new capabilities for the Vector which were included in firmware 1.4 that was released in November 2019.

Enable a drum Voice

To enable a Drum voice, choose one of your PARTS (must be between 5 and 8) and go to GLOBAL settings, dial to the PART and change it from Mono (or Chord) to become a Drum part.  In the below photograph, I am using Part 8 which I previously named KORGX.  I have routed the 4 voice outputs to send signals to my Jack Expander module (trigger outputs 5 to 8), and each are connected to CV inputs of my ALM SALMPLE.  You may alternatively use the Vector Gate and Velocity OUTs instead of triggers if you want to control volume as well as gates.

Routing Drums

Routing is achieved by going to the PART routing page and selecting (in this instance) D8.1, D8.2, D8.3 and D8.4 against the output you want to employ.  “D” stands for drum voice, “8” is my chosen drum Part and dot one through four are the drum voices. In this build I observed that dialing too fast can confuse the Vector, but I found dialing slowly or using SHIFT and dial to jump increments was flawless.  This also works for MIDI connected drum machines.

Entering Drum Hits

Each preset step is drawn with four horizontal underscores, which represent the individual drum voices available per step.  The maximum number of drum voices per Part is four, but you can easily create more than one Drum part. The heavier horizontal line under voice one in the above photo is the 'cursor' and you can move that left to right using Encoder 9 to select the voice you want to edit.  

Pressing the Step Encoder (1 to 8) or the associated white key (1 to 8) will enable or disable a drum hit for the cursor selected voice.  You can then use the Step encoders to dial velocity levels if you are using Gate/Velocity outs and not Triggers.  This sounds complex, but once you get into it, this is a very fast way to create a drum pattern and also edit during performance.  Kudos to Jim for finding a really great way to present this feature within the Vector.  

Additional Comment on Drums

The genius here is that it is all done in one screen and does not force the Vector to become an XOX box, which I also love, but would break the consistent UI that Jim has achieved.  The fact I can use Triggers on the Expander and not consume Gates is also an outstanding design choice, maximising the capability of the modules.  

As is normal for the Vector, Drum and Chord parts can be from one to 64 steps in duration and once configured, you have access to all the usual chance operators, sub modulation and Control page madness.  If you already own a Vector, just let that sink in for a minute...

Custom Chords   

Also new to firmware version 1.5 is Custom Chord voices.  If you remember a few weeks ago when you started reading this article (yes it is very long), I mentioned there were three modes for parts being Monophonic, Chord and Drum voices.  Chord mode is split between three types, being prebuilt chord voices, basic intervals, and Custom Chords.  

Enabling Custom Chord mode is similar to Drum voices, however once you have applied it to a Part (being Part 7 MOOG! in my photograph), you then go to PITCH and press a combination of Encoder and Edit keys to enter the Custom Chord mode.  Once you select Chord mode, you have options for pre-configured chords (as explained above), single interval additions, and four voice Custom Chords. The photograph below shows a mixture of the different chord modes (custom 1, interval 2, and pre built 3-6). 

For a Custom Chord (see Step 1 below), each Step presents the bass note of the chord. The three numbers directly to the right are your additional intervals.  You can use some or all of the available voices to create a Custom Chord. The numbers represent semi-tone steps from the bass note. A tied note between steps will cause any common notes to be held instead of re-triggered, which is pretty nifty!  

For example, to build a C minor you might select C, 3, 7 and 12 for four voices.  You can also spread chords across four octaves ascending from the bass note.  Intervals are represented numerically from 1 to 12 (blank being 0 for unison), and a small graphic will appear to show you are in the second, third or fourth octave range. 

Sync to your DAW

I own a couple of MOTU audio interfaces (828es and 8pre) and decided to run time-sync from my PC DAW via the excellent Silent Ways (Expert Sleepers) VST.  The benefit of this approach is that your DAW-to-Eurorack timing should be rock solid, and far superior to MIDI (especially USB MIDI based clocks).  Part of the beauty of Eurorack is the solid timing, so why ruin that with MIDI clocks, especially if you are like me and run a Windows DAW, where USB is granted low priority to access system resources.  Macs apparently have better USB timing. 

The best thing you can do for your DAW-to-Eurorack explorations are get on board with Silent Ways.  It sends CV based time out from your audio interface, and my understanding is that for RUN/STOP and TIME, you don't need decoupled audio outputs as you would if you were sending LFO signals. 

I have personally run SW SYNC via TRS audio outs (using mono 6.2 to 3.5mm cables) and also via the stereo headphone out (using a stereo-to-dual mono splitter and separate 3.5mm patch cables) with equally excellent results to various sequencers, including the Vector, Circadian Rhythms, and Pamela's New Workout. I generally run the SW SYNC output to a buffered MULT then plumb timing in the rack from there.  

Vector and Jack Expander Calibration  

Each Vector and Jack Expander has a serial number.  The Vector will come loaded with the calibration files that relate to the Jack Expander with the same serial number.  So, if you buy both units and they have the same serial number, you are good to go.  If not, then emailing Five12 will get you the calibration files you need and which are easily dumped to the Vector via USB.  You will need to supply the serial number of the Jack Expander module that you own.  Mine is number 83 which you can see below.   

Backup Your Calibration Files 

Early on, I accidentally deleted the pre-loaded calibration files and needed Jim to send me replacements.  If you are a new user, you should back up the files in case you do the same thing. I emailed Five12 and had the replacement files by reply email the same day.   Below is a screen shot of the EXCAL and VSCAL DAT files used to calibrate the Expansion and Vector modules.  The Project folder is the one you want to backup to save your precious work.  


Jim is passionate about his products and among the best in the business for providing support, feature roll-outs, and firmware revision. The Vector and Jack Expander are very well-engineered modules.  Jim is reachable via the Five12 website forum, and issues tend to get fixed in the near term. 

The Five12 commitment to new features has been demonstrated consistently since release, especially with the recent Custom Chord and Drum Voice additions.  There are still more refinements planned as the Vector still has legs for more development.  A reasonable user-base has evolved and you can often find answers on the official Vector forum or the Five12 Vector Sequencer User Group Facebook page.  


  • The Vector easily becomes an excellent central brain for your eurorack and MIDI hardware.  
  • Syncs beautifully with a DAW, especially when using SW Sync by Expert Sleepers.  
  • Deep levels of control accessed through an excellent user interface.  
  • Five12 continues to roll out new capabilities and have a road map that will keep the Vector relevant for a good number of years.  
  • At heart, it is really enjoyable to use and will help inspire you to write music.  


  • Playing notes from a connected keyboard through to a destination device could be a little easier than it is today.  
  • More Chance Ops!  I am kind of an addict.  There are a lot of them but I am greedy.

I bought the unit that I have reviewed for personal use.  

A Few Questions for Jim Coker 

1. You have a proven track record with a respected software product in Numerology.  What made you feel like moving into hardware? 

Jim: A big part of it was meeting the right engineer, in this case, Joe Grisso of Detachment3.  In addition to being a great guy and easy to work with, Joe was able to convince me that the latest generation of embedded ARM micro-controllers had what I would need to build a first class sequencer. 

2. What is your programming background?  

Jim: I’ve been a professional programmer for a long time now.  Before I got deep into the sequencing stuff, I did many different kinds of programming gigs, including web stuff, database programming, even a fair bit of compiler implementation.  I have a Master’s degree in computer science from Stanford University, so my education is pretty traditional in that way.  But it was also at Stanford where I first got into computer music through a couple classes in their CCRMA group. 

3. How did you adjust your software knowledge to hardware design?  

Jim: The biggest change, of course, is having to pay much more careful attention to how memory is being used and how much CPU is available - everything evolves around those limitations.  But it is also liberating: with a much simpler set of APIs and graphical options on the displays, it is much easier to spend time on useful features. 

4. What were the biggest things you learned from designing and releasing the Vector? 

Jim: There were many little lessons learned from finding a way to organize the UI from Numerology to a much more compact format.  Some of that came from having a chance to re-group things like sequence controls and sequence operations into one place. Probably the biggest breakthrough was the design of the Chance Ops. It came from trying to find a way to fit the random jump and probabilistic mute options from Numerology’s sequencers into the Vector’s UI.  Having separate pages for each didn’t really make sense, but having an operation that could change per step did — and that opened up the possibility for all kinds of interesting tricks to be added.

Full disclosure   

I created and admin the "Five12 Vector Sequencer User Group" Facebook page, but don’t let that convince you I am biased.  If you are on my Facebook feed, you will see I am merciless in selling gear that isn’t right for me.  It’s all part of the eurorack journey, right? I also have no affiliation with Five12 at all, beyond being a really happy customer and doing firmware testing from time to time.  


Leave a comment

Add comment