Sequentix Cirklon review

Like the P3 before it, the Sequentix Cirklon is a fairly niche piece of musical equipment. It’s a MIDI sequencer (with options to expand to CV outputs for modular / vintage connections). And that’s it. No sounds, no samples, no effects, no audio inputs or outputs. Just MIDI and CV.

If you know anything about the Cirklon then you probably know that it has somewhat of a cult following. Cirklons are hand made by Colin Fraser in small batches. There is a waiting list to buy one and second hand units tend to go for new prices because customers can skip the queue. The build quality of the Cirklon is extremely high. A month ago, the LCD backlight failed in mine and because it had happened to two other users as well, Colin switched his LCD suppliers because, and I hope he doesn’t mind me quoting him here, “a 1% failure rate is not good enough”. He repaired and upgraded my LCD free of charge and even offered me a choice of colours (I chose black of course).

Sequentix Cirklon

So, we’ve established that the Cirklon is a labour of love, built to high standards and extremely well serviced. But why would you want one? If you’ve never played with one before, I’ll try and explain. Here’s a list of things the Cirklon can and can’t do:

Can do:

– create patterns by either recording live MIDI input or step sequencer style programming
– patterns can be either piano roll style with high resolution (called “CK” patterns) or rigid step sequences at a division of the master tempo (called “P3” patterns)
– an individual pattern can have multiple “bars” (not necessarily one bar long) which can be individually different, chained together, transposed etc.
– patterns can contain up to four “Aux” rows which can randomise, grab values from other tracks, send out other MIDI values or generally alter the pattern or other patterns in a variety of ways
– there are up to 64 tracks, each of which can play a single pattern plus a “fill” pattern which will play when the Fill key is pressed
– each track is assigned an “instrument” which tells it is which port and MIDI channel to use
– “scenes” store all information about which patterns are played on tracks as well as tempo, key and other pertinent values
– scenes can organised into “songs”
– with a CVIO board and break out box, Cirklon can output CV and gate to control analog equipment

Can’t do:

– sample or or synthesise – the Cirklon can make no noise by itself
– act as a editor/librarian for synths/drum machines etc. although there is a rudimentary system for setting up MIDI CC# parameters for connected equipment so some editing is possible

Sequentix Cikrlon

The Cirklon does a number of things better than any other sequencer I know. It positively shines at creating generative, semi-generative or pseudo-generative sequences. What the hell do I mean by that? I’ll give you an example.

On Track 1, I setup a simple chord track. This is done using a P3 pattern, which can use Aux rows which can turn a monophonic pattern into a polyphonic one. Each Aux row can output an additional note to the main note in the pattern at an offset like +3 semi-tones. So it’s very easy to input a sequence of major/minor chords or whatever note intervals you choose. The beauty of this approach is that you can simply adjust the base note to transpose an entire chord. And because the Cirkon can force everything to a chosen key and scale, nothing ever sounds bum. Because these are the main chords of my mini song, I’ll set this pattern to run at a slow division of the main tempo so that each note (or chord in this case) lasts say 1 bar.

On Track 2, I setup a simple melody. Again, I use Aux rows, but this time I use them to grab notes from Track 1. Then I use another Aux row to transpose these notes and maybe a third Aux row to randomise one or two of the notes in the pattern by say +/-5st.

On Track 3, I could do the same again, but use different patterns or track lengths and different transpose values to make a completely different melody. Remember that all the notes in the melodies of Tracks 2 and 3 are being grabbed from Track 1. Or if I’m feeling adventurous, I could grab the notes from Track 2 instead. Nested grabbing!

I now have some chords and a couple of melodies. The melodies are complete generated by the chords set in Track 1. If I change those chords, the melodies of Tracks 2 and 3 will adapt and change. This is what I describe as “pseudo-generative”. There’s a ton of ways to elaborate on this. I could randomise some of the notes in Track 1, or use Aux tracks to change the tempo divisions of any (or all) of the tracks. Things can become complex, but there’s a huge amount of power here.

That is a single example of what the Cirklon is so good at. There are countless other ways you can create complex, randomized, poly-rhythmic or generative patterns and the results can be truly stunning. Of course all this complexity can be difficult to master. There is a lot to learn, but the Cirklon’s nice big screen, excellent manual and helpful online community mean that answers are never far away.

Sequentix Cirklon rear panel

If you own a lot of vintage synths or a modular, the CVIO option would probably make a lot of sense. With 16 CV and 8 gate outputs which are totally configurable inside the Cirklon, it’s extremely powerful. Equally if you’re a software user, the Cirklon has six virtual USB MIDI input/output ports so your soft synths can be integrated into your compositions. Combine the two and you have a very powerful MIDI to CV convertor.


The Cirkon has very quickly become the centre of my setup. The timing is absolutely rock solid. I can only think of two sequencers I’ve used that felt this tight, the MPC60 and the Atari ST. Doubtless if you’ve got this far through the review, you’ve probably checked the Cirklon and it’s sobering price. The CVIO will bump the price up even more. Whilst it is expensive, it’s worth remembering that the Cirklon is many things. I sold my Edirol UM-880 MIDI interface not long after getting it as the Cirklon not only fulfils all the sequencing I could need, but also acts as a MIDI interface. I was also able to sell my dedicated Analog Systems MIDI to CV convertor: again the Cirklon took care of that. I even sold a few of the sequencing modules from my Eurorack modular setup (although I will probably reinstate these at some point).

In short, the Cirklon is a chameleon in the studio, but at it’s heart is a highly creative device which can interface with just about any modern or vintage electronic instrument. It’s complex, yet musically rewarding and built to a very high standard.

Frankly, I’m in love with it.

15 thoughts on “Sequentix Cirklon review

  1. Hey – thanks for this excellent review. After a long wait i finally got my number pulled and have a Cirklon coming to me shortly.

    I’m curious what your thoughts are on just the CK real time sequencing vs an MPC for sequencing hardware synths. Extra features aside.

    I have a sync gen and have seen the litmas tests – but would love to hear from someone who has both units.


    1. Hi Michael,

      Sorry it took me so long to reply. Cirklon really encourages programming and experimentation. The MPC is more of a record/playback sequencer, in that it doesn’t give you much in the way of editing tools to muck about with what you have already. Both are solid sequencers, it just depends on how you like to work.

      – Rory

  2. re: CVIO breakout board, just wondering if the cirklon can be clocked by other analog CV gear via gate IN or is it only able to be clocked via midi? thanks for the review

    1. Only MIDI currently. CV input has been discussed many times by Colin. He certainly planned to do some kind on CV/Gate input (the clue is in the CVIO initials!). Some of the sockets on the breakout box are even labelled as inputs, but the software can’t use them yet.

  3. Thanks for this post.
    Do you know if the Cirklon is polyphonic on each track ? If yes, do you know how many notes can be play at the same time ?

    1. Hi,

      There are two types of pattern in Cirklon: P3 and the CK. P3 patterns can be up to 5 note polyphonic and CK patterns are unlimited as far as I can remember. Hope that helps.

      – Rory 🙂

  4. Hi,
    I’ve desperately been trying to find out the size of the Cirklon without the rack ears but that has been impossible so far. Could you tell me how big it is in millimeters without the rack ears please?
    I’m waiting for my delivery date at the moment but I want to know if it’ll fit in my roadcase!


  5. Hi, very good review!

    Are there any limitations on the number of CC’s it can send on each track?
    One of my devices is a pedalboard with 8 footswitches, and each footswitch is activated with an specific CC

    Thank you (and sorry for my english)

    1. Thanks Francisco,

      Not a clear answer but… There are two types of patterns. P3 patterns (step-sequence patterns) are limited to 4 cc#s (one per Aux) but you can play many patterns simultaneously to the same instrument, so you could get round it that way. CK patterns (192ppq piano-roll style patterns) can hold more than 4 I think, but I’m not sure what the limit is.

      – Rory 🙂

Leave a Reply

Your email address will not be published. Required fields are marked *