How to build your own Continuano

#1

With the new version of the Senselmap application it is finally possible to release a first version of an imho very interesting overlay I have been working on in several iterations for quite a while now.

Introduction

The Continuano can best be described as a combination of a piano and the Haken Continuum. It frees the player from the choice between enabling pitch rounding globally or not and allows both at the same time: Notes with initial rounding to the equal tempered twelve tone scale can be played e.g. for fast passages, chords and accompaniment like with a piano. And pure intonation of intervals, playing of scales outside of the twelve tone system or “fun with interferences” (between very close frequencies) is possible in a pitch rounding free sub-cent-resolution area like with a Continuum with pitch rounding off.
Other than a piano or a Continuum it is super compact - full size velocity senitive, poly aftertouch, 3d-touch keys with up to eight octaves foldable to the size of an iPad, easily fitting into any bag - that’s nice :slight_smile:
And it is a MIDI class compliant, MPE compatible controller that can just be plugged into any compatible hardware or software synth.

Idea behind the concept
Essentially it is the continuation of the idea behind a piano. Some early key-based instruments were optimized for diatonic playing which works well for church modes etc. There we mainly play in the lower diatonic “row” of the piano that is comprised of seven (almost) equal-width keys per octave. The second piano “row” above the first diatonic one offers twelve keys of equal width and (nowadays) equal tuning offset of 1/12th octave between keys - these are the chromatic keys. Thus when purely playing on the chromatic row, each interval has the same width in all tonalities - with the aid of this second row pieces can transpose between tonalities at will.
But equal tuning also makes some compromises: Pure intervals get rounded up or down to the next multiple of 1/12th of an octave. Additionally the choice of playable notes is limited to the notes of the chromatic twelve tone scale.
The Continuano now introduces a third row above the chromatic row - which is continuous. So arbitrary pitches can be played, like on a fretless instrument - think violin - or Continuum. Which allows all the pureness and fun mentioned above.
The first two rows behave like on the piano - almost. When touching the surface the pitch always exactly corresponds to the corresponding equal tempered note. But from there on pitch can be bent up and down as desired.

Building your own Continuano
Such an instrument can (as far as I know) not be bought. (*) So here some instructions to build your own based on (optimally several) Sensel Morphs. Using the Morph has some aspects to consider: The panels have lower touch sensing capabilities at the borders. So after some experiments I came to the conclusion to just accept the gaps at the borders as an inherent property of the instrument and use slightly wider finger positioning when playing intervals that contain a gap. What you get with accepting the usage of smaller, individual Morphs is the folding option of course - 2-6 stacked Morphs in a bag is hard to beat transport-wise :slight_smile:
Have decided to go with three octaves over two Morphs (or 18 semitones per Morph). The reason: This spacing is almost indistinguishable from the spacing of both a standard piano - and of a Continuum, so both pianists and Continuum-players should feel right at home. (**)

For playing around with the idea one Morph is sufficient. Imho the fun starts with two Morphs though, which offer three octaves and 36 semitones. Currently I personally use four Morphs for six octaves and 72 semitones. With five Morphs and 90 semitones you would already be above the range of usual 88 key pianos. And if you are so lucky to have six you could use one spare Morph for swapping overlays, e.g. for synth control etc.

This zip archive contains all the files you need to build your own Continuano:
Continuano_2019-05-13.zip (91.7 KB)

  • The senselmap files for up to four Morphs (if you have more then adapting a fifth or sixths should be easy with the SenselApp). These maps were created on Windows. In case you cannot import them (e.g. on Mac), look at the bottom of this thread for a description how to convert them: Can't import maps to Windows
  • Paper bags that can be used to create overlays from paper - for first experiments
  • A larger overlay that can span several Morphs (here an example for four - can of course be adapted to more or less). This is best printed on neoprene (for four Morphs: 100cmx14cm). I have used the 1000 g/m^2 Neoprene “cut on line” option from Contrado which is about 40€ for the first and about 11€ for each additional overlay. (Not affiliated with them, chose what works for you :slight_smile: ). It can easily be attached by gluing e.g. some woods or stacked cardboard material with the height of a morph to both sides and an additional cardboard material to the bottom (see picture).

    The contained afdesign files can be edited with Affinity Designer).

Then transfer the maps to the Morphs (make sure to set pitch rounding in the global settings of each Morph to “none” - we get pitch rounding on initial touch for the diatonic and chromatic rows by setting X to relative for all related areas and “Absolute X” for the rounding free area.

Now get yourself a USB hub with at least as many ports as you have Morphs. Optimally one that can also be powered, so you can charge your Morphs faster (for playing you can use the USB hub in passive mode as long as the Morph batteries are full).
Then find an (optimally MPE compatible) synth of your choice (hardware or software synth - all goes, thanks to the Morph-firmware the Continuano is MIDI-class compliant). Play!

Gratulations, your Continuano should be usable now - have fun! :slight_smile:

Notes
Last but not least some suggestions for an improved SenselApp that would allow to make the Continuano even nicer:

  • Round-to-target: An option for an MPE area to round to the base note if the finger is in the area and stops moving for some definable time. That way you could start in an area with a key, slide the finger up into the rounding free area to go wild and then return to a defined-pitch key to round to the target note that fits the accompaniment. (This would of course have to be a per-area function, so it does not affect the rounding free area)
  • MIDI-channel range per MPE area: The ability to define a MIDI channel range for each MPE area would allow to play different sounds with the diatonic and chromatic and with the continuous zones - e.g. for accompaniment and lead voice.
  • Last but not least: A 4-6 times wider Morph would allow to get rid of the gaps. Sure, the resulting instrument would be bulkier - but not heavier than the equivalent separate Morphs. Would also reduce the amount of cables and need for a USB Hub. Don’t regret to have the “mobile edition” now - but would buy the large version in an instant (and know of others who would do the same)!

Remarks referenced from above
*: Roli Seaboard might look similar on first sight but is actually quite different: It does not have the equidistant spacing of the “chromatic row” that a piano still offers, afaik always rounds to at least quarter notes and has a very narrow “strip” below the waves that isn’t meant for Continuum-like usage of absolute y-position for starting the timbre of a sound with a corresponding start value. So imho the Seaboard is great if you want to play hands-on vibrato and some glides while still staying close to the keyboard metapher.
The Continuano on the other hand is closer to the original idea of both the piano and the Continuum, keeping the equal-spacing of intervals in the chromatic piano-like row and allowing pure intonation, scales beyond the twelve tone scale and absolute control over y in the pitch free range.)

**: Have also experimented with two octaves per Morph (as with the Sensel piano overlay). But there particularly the rounding-free area is challenging to play: For two adjacent semitones it is barely possible to position the fingers side-by-side, it’s like a violin in the upper registers where fingers have to “make place” for each other - possible but not easy.

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#2

I’m reluctant to map anything to the “no overlay” slot, as I’m fairly sure that will disable the raw data I rely on elsewhere.

I’m thinking the inventor’s kit overlay might be a reasonable compromise, but of course, that accentuates the gap between units.

It’s a shame; I really like the neoprene idea.

#3

Afaik if you initialize the Morph from the C++ API then it switches to “raw mode”, no matter what you have set via SenselApp. (To be checked with recent firmware versions, haven’t tried this for some time…)

Have built a Continuano test application in C++ based on MEC about a year ago (when SenselApp wasn’t available yet) that had a number of additional features (interpolation over the gap, rounding on target for the diatonic and chromatic zones, mpe midi channel per zone etc.). The big advantage of using the internal firmware (configured via SenselApp) is the MIDI class compliance - and better customization options for non-coders of course.
From experiments with that test application my experience was: Yes, the gap can be made smaller than with the SenselApp, but pressure measurement is becoming inconsistent when reaching the metal frame - pressure values become a lot smaller for the same pressure because the frame is absorbing some of the pressure force. Some correction could be applied but still accurracy goes down. And when having no gaps (as I had with my initial prototypes) this means that some notes “on the gap” are less expressive than others. Which is imho more disturbing than learning to slightly increase the finger distance when playing “over the gap”. What you gain is that every possible pitch can be played with uniform pressure and full expressiveness.

Perhaps the sensing on the borders could be improved by removing the metal frame (which is the resistance the finger runs into when playing “on the gap”) and putting the sensor plates side by side. But I didn’t dare to disassemble my Morphs…

After playing a little the gap imho becomes acceptable, because it’s quite predictable, so the brain can learn to adapt. (When walking and moving and looking the brain performs constant subconscious processing to make the experience look easy to us :slight_smile: )

Edit: If you mean “one big SenselApp-configured XYZ MPE area” with “raw” (instead of the full pressure matrix that can be obtained via the C++ API) then yes, unfortunately only one slot for “no magnets” is available…
One hack could be to try to find small, flat magnets and position them at the locations where they reside in the innovator’s overlay - and hope that the Morph can be tricked into detecting the Continuano neoprene overlay as innovator’s overlay. Then “no overlay” would remain free for something else in SenselApp.
Hopefully the magnets will be provided soon by Sensel - optimally together with a whole “address range” of magnet positions that can be used for custom Innovator overlays 1-256 or something along these lines.

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#4

I like this idea, although I am not sure I could find the materials and tech to actually make it; it seems to be an interesting workaround for the problems in the conventional Keyboard overlay and in instruments like the Seaboard. Any chance of your making some to order for folks who don’t have access to the makertech? :slight_smile:

#5

There are shops that can print the neoprene overlay for you. I also didn’t do this myself.
E.g. go to contrado.com (or de.contrado.com) - or another shop of your choice. Then: Fabric Printing/Fabric Type: View All, select Neoprene 29.5 oz, Start Design, set the size to 100cmx14 cm (for the 4 Morph variant or in general number of morphs x 24cm+2x2cm for the borders). Set “how would you like the edge” to “cut on line” and finally upload the overlay image.
Costs about $50 for the first and then about $7 for each additional print (for 4 Morphs), takes about 2-3 days to print and arrive.

Or you could use the paper bags that can be printed with any standard home/office printer and glued together with normal glue or Tesa. The haptic feeling is of course better with the neoprene surface, but the paper overlays also do their job for experimenting with the idea. I like these bags more than the Innovator’s overlay. The template is in the zip above, ready to print it out.

If you don’t have wood, you could also glue together cardboard until it has the needed height.

Me selling some would mean I’d have to register a business - with all the paperwork for tax declaration involved (even if I stay below the threshold to actually having to pay anything). Also sending stuff around (at least outside Germany) presumably isn’t much cheaper than ordering a print by yourself I fear. But if people inside the same country organize they could save a few Euro/dollars with a “group buy” of the neoprene surface, so it’s not $50 but closer to $7 each.

1 Like
#6

Fair enough. I guess everything done for the first time is a bit scary. :slight_smile: I will have to see who in the US does work like Contrado, since shipping to the States is likely to be more expensive than the product! Thanks for the feedback.

#7

The first link is afaik to their US site.