Music for Tablets: Quantum Sequencer by Anthony Saunders

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At long last, the Swiss Army Knife of iPad MIDI sequencers, Quantum Sequencer,by Anthony Saunders arrives.  And it’s a honey.


by Warren Burt, Nov. 2017


Many years ago, way back in 1970, while an undergraduate student at the State University of New York at Albany, I began working with a very large Moog system, called the CEMS system, designed by computer music pioneer Joel Chadabe.  The system featured, among other things, eight Moog sequencers. Here’s a picture of it, with a very young Joel Chadabe in front of it.  You can see one rack of four sequencers in front of you.  On the right side of the photo, in profile, are the other four.

It was one of the most powerful analog synthesis systems in the world at the time, and I very much enjoyed working with a machine that had that much control, so much so that when I went to graduate school at the University of California, San Diego, from 1971-1975, in the arrogance of youth, I felt that their very large Buchla system, which only had four sequencers, was a step down.  In any case, I was already striving for the dream: a multiple sequencer system in a platform I could afford, and which I could carry with me.  By the early 90s, with a DOS laptop computer, and software available at the time, such as Algorithmic Arts’ Music Box, and various synthesis programs, I had achieved that dream.  But when tablet computers began to appear in the mid-2000s, I noticed a lack of what you might call “polyphonic sequencer programs” that weren’t based on the DAW paradigm.

One of the best iOS sequencer programs was Analog MIDI Sequencer, by Anthony Saunders.  Although it was only a single voice sequencer, that sequence could have values for pitch, duration, loudness, MIDI channel, up to sixteen MIDI continuous controllers, probability, humanize controls, and swing levels for each step, and one could step through the sequence in a number of ways.  Additionally, one could have optional chords on any step, and there were a number of “ornaments” that one could apply to each step as well.  So for a “monophonic sequencer” it was very powerful, and has long been a favorite of mine.  But I was still longing for a multi-sequence app that would allow me to think compositional thoughts like the ones I had had back in my student days, one that I could carry around with me conveniently on a tablet.

More than two years ago, Anthony Saunders said that he was working on a multi-sequence version of Analog MIDI Sequencer, and I eagerly waited for its release … and waited and waited.  On Anthony’s Facebook page, I followed the developments, as he added feature after feature, and the release date kept receding into the future.  But patience was worth it, because in early October, Anthony finally released the new sequencer, called Quantum Sequencer, and it’s an incredibly powerful system with more features and abilities than I could possibly cover here.  Building on the framework of Analog MIDI Sequencer (and owners of that software should run, not walk, to get this one), it adds a number of features, such as six simultaneous sequencers, each of which can have its own tempo, MIDI channel, number of steps, way of advancing through the steps, transposition, volume, etc.  Additionally, each sequence can generate four sub-sequences, all on the same MIDI channel(s), but each of which can also have its own tempo, number of steps, way of advancing through the steps, etc., bringing the total number of channels of information available to 24.  That should be enough polyphonic possibilities for anyone.  The number of steps available for each sequence has increased to 64, and the number of kinds of progressing through the steps has also increased.  Here’s a look at the main page of Quantum.

At the top you’ll see 16 sliders.  There are four ranks of these, selected with the buttons below the sliders on the left, to give access to all 64 possible steps.  The small selection buttons below the sliders on the right select a number of values for these sliders, so that you can, for each step, have a pitch number (and additional pitches as a chord), with possible ornamentations for each step; a velocity; a duration (which can last up to 400% of the notes value); a MIDI channel for each step; sixteen possible control values (including pitch bend, aftertouch, program change, sysex information as well as standard MIDI CCs); time (a duration for each step, as opposed to the sustain value set in the duration sliders); swing; probability settings for the step; humanize features; and muting.  Each of the six sequences then can have its own tempo, start and end point, kind of looping and progress through the steps, transposition, overall volume, and up to eight MIDI FX can also be applied to each sequence.  Additionally the sequence can be inverted or reflected around a chosen pitch, and, as mentioned before, each sequence can be divided into four sub-sequences.  Along the left, you’ll see performance controls, and a Page control for selecting which bank of three sequences you’ll be looking at. (On the iPhone, only one sequence is displayed at a time, with the Page control then scrolling through the available sequences one at a time.) Tempo, global transpose and volume are all available at the bottom of the page, as well as the all-important stop and play controls.  So here is my dream sequencer, on an iPad or an iPhone. In fact, Saunders has made the program compatible with all iOS versions from iOS 9.3 through to the present iOS 11 versions, which means that the program runs flawlessly on my ancient iPhone 4, as well as on my iPad4, my iPhone6s, and my iPad Pro.   (Additionally, ThumbJam runs on all those platforms, and it can run as an eight-channel polyphonic sampler.  So not only have I achieved my dream of a poly-sequencer system in a portable platform, it can also now exist on my phone as well!)

Here’s a picture of the kinds of moving through the sequences that are available in Quantum.  The Forward Skip options are particularly intriguing.  Imagine the same pitch sequence on two different channels, but on one channel, the sequence is progressing with every third step of the sequence (F+2), while on the next channel, the sequence is progressing by leaping to every fourth step (F+3).  I don’t know what kind of counterpoint that would be, but it’s one that I’m eager to start exploring.  Also, three kinds of Random are explored – one where one leaps all over the sequencer, and two where the leaps are much more constrained, to result in new patterns which have the potential to resemble the original patterns quite strongly.

And here’s a picture of the kinds of randomizing that is available to generate information for any of the sets of sliders in Quantum.  It also generates various kinds of slopes, and can invert, and reverse values, etc.

MIDI Learn is supported for most of the controls on the main page.  Pressing the Learn button at the top right brings up this page where MIDI Learn can be set up.

And here’s a picture of the Added Notes function available for each step of each sequence, where you can set up traditional, or non-traditional chords to play on each sequencer step.

Quantum also lives quite nicely in Audiobus 3.  It can be used either as a MIDI source, or as an Audio source.  In this picture, an instance of Quantum with multichannel output is connected to ThumbJam, which is accepting the multichannel MIDI from Quantum.  The audio from Thumbjam is then being processed through Sugar Bytes Turnado.

Finally, here’s a picture of another new feature in Quantum – a Mixer Page, where you can perform selection and fading of the tracks in real time, or have them controlled with an external MIDI controller (through MIDI Learn).

There are many other features in Quantum that I haven’t mentioned here, such as the ability to quantize any sequence to any key or into selected scales, Ableton Link capability, selectable record options from external MIDI, etc.  It’s a very deep program, and it’s incredibly feature rich.  I’ve just started working with it, and already I can see that it’s going to become one of my major compositional tools.  The structures implied by its various potentialities boggle the mind (my mind, at any rate).   With all this power, there is just one feature I’d like to see added – I’d like to see more tempo divisions added to the ones already available for each sequence.  For example, 1/7, 1/9, 1/10, 1/11, etc. tempo divisions being made available would make this little black duck very happy indeed.

Many people might prefer working with a DAW-style sequencer, but for those of us raised on analog sequencing, Quantum is indeed a (sorry) “quantum leap” backwards, to an earlier model of electronic music control, and a “quantum leap” forwards, to a future of great control flexibility and combinatorial potential.  And at $9.99 USD, what have you got to lose?  It’s cheap, it’s insanely powerful, and it works on just about every iOS device.  I can’t see any reasons not to get it, and lots of reasons to have it.  Many thanks to Anthony Saunders for realizing the potential of the earlier Analog MIDI Sequencer into the polyphonic power of Quantum. Buy this one now.



$9.99 USD on the App Store





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