Thesys, a midi sequencer

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It’s not new, but we think it’s worth it. Thesys, from Sugar bytes, is a VST, Audio Unit (PC and Mac) midi step sequencer plug-in. It is used to create midi patterns and is designed for use with third party midi instruments (but includes a basic but usable internal synth too). Imagine it as a sort of steroid-pumped arpeggiator for anything that accepts midi signals, but with a lot extra on the side. If that just confuses you, there is a good amount of information on the company’s website that can help with understanding the plug-in. There are several helpful video tutorials (like the one below) to help you get over the initial learning hump of routing the plug-in to other instruments, and the plug-in comes with a very clear and concise manual.

There are three main midi sequencers that control pitch, velocity and gate. It’s easy to enter values on each sequence. They can be input directly into the sequences with mouse clicks, or stepped in with a midi keyboard. There’s a copy, paste and random button to experiment with, and a reset button to start over. The pitch can be further controlled with a scale function that allows the user to choose what mode the pitches are in – from the usual chromatic (all notes), major, and minor modes, to more unusual modes such as Bebop, and Balinese. Each of these sequences can be saved within a larger pattern of up to 16 sequences that can then be repeated up to 16 times.

There are two more sequences that really take the plug-in to a more flexible and interesting level. The first is called the Performance sequence, and contains five levels of different set subsequences – Octave, Bend, Chord, Roll and Random. These sequences are all fairly self-explanatory – you can raise or lower each step in the sequence by one or two octaves, you can add a variety of different pitch bend patterns to each step, a variety of different chords, a variety of different roll patterns, and you can choose to randomize 17 different specific aspects of each step, such as pitch, gate time, velocity and so on.

The fifth and final ‘modulation’ sequencer is where the plug-in gets really interesting. It contains 8 sub-sequences, each of which can be set to any CC number. In other words, through this modulation sequence, you can control any parameter that can be affected by a midi signal. The limits are seemingly endless! Applying the sequence to a cutoff filter, for example, could create a really interesting sound other than the usual sweep.
I didn’t try, but presume that there are no issues for using this plug-in on hardware synths that are connected into the DAW that you are using too.

These five step sequencers linked together provide an almost limitless supply of options for delving into some really deep arpeggiations and patterns that would be impossible to play live, and really time-consuming to program in otherwise. Sugar Bytes are definitely living up to their claim of ‘doing more stuff with less buttons’! If all this ‘sequencing’ talk is too daunting to start with, there are 4 banks of preset patterns to give you a jumping-off platform.
If that’s not enough, on top of the midi sequencing available, there are several live performance triggers, creating even more variations, such as slowing down, half speed, looping specific portions of the sequence, muting, velocity gating and more. The sequences can also be pitch shifted, and triggered through midi hardware (keyboard, or other controller) This adds another dimension to the usefulness of Thesys and it would be interesting to see this in live use.
I had a lot of fun using Thesys to trigger sample programs such as Battery or Kontakt, and create some interesting grooves with atypical samples. Unfortunately Logic users, due to Apple’s AU implementation, are likely to be disappointed by Thesys’ performance (if used to control external v.i.). I’d recommend using it with Live or other VST capable hosts.
A demo version is available.

Price: 99Euro/129 USD

This plug-in presents an almost limitless supply of options for delving into some really deep arpeggiations and patterns that would be impossible to play live, and really time-consuming to program in otherwise.

Product’s page


Very flexible and simple step sequencer that can create some very organic and evolving patterns.

Great addition of live performance triggers for further manipulation

Great value for money


If you don’t own a decent arpeggiator (and even if you do), this brings new life to synths, providing ways of creating that weren’t possible before. If you don’t like midi, stay away.


There is no Midi Learn for performance triggers.

Little bit fiddly – some of the aspects of the GUI are a bit small.

Not really usable in Logic, due to Apple’s AU implementation

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Thesys, a midi sequencer

by Andy Dollerson time to read: 3 min