I just ran across a manufacturer of a switch mechanism with those 2 actions:
Making an electrical connection to the cap’s capacitive mesh, which doesn’t breakdown from switch motion is one of the tricky aspects.
OK, I’ve been away from replies to this for a few days because of personal matters. so now I’ll catch up with this.
I described my particular case as a CHURCH ORGANIST… Now then, If you’re familiar with or ever seen a church organ, there’s 2 concepts of design. They are Draw Stops (hence pulling out all the stops) which is the original design of not only church organs, but early pump organs and reed organs in stately homes, etc. The second design is known as Tab Stops. Over the years, they’ve changed in design concept from front facing tab stops with either hydraulic, latch coupling or electro-magnetic actions, Tongue profile tab switches which are electro-magnetic action, or today’s new standard which are “Momentary Rocker” tab switches which have no mechanical recall, just an LED set behind the tab as a semi-opaque plastic with the function name etched to the centre of the tab. There is also what’s called a “Soft” Draw stop. This design is a cheap version of an electro-mechanical or Electro-Hydraulic or even Vacuum Hydraulic stop, however, thisdoes not have any form of physical actuator to recall physical position, it is just a momentary switch reverse set, so that when the stop is lightly pulled out and sprung returned, it will either switch on or off, the stop has an LED through a tube in the centre of the stop body where a semi opaque dome finish face is inscribed with the stop, coupler or function.
As previously discussed and my attempts to make this clear. An organ console layout covers multiple keyboards “Manuals” as well as the pedalboard, so, these are divisions, an average church organ spec / cathedral organ spec focuses on 4 or 5 divisions, they focus on Pedal, Solo, Choir, Great & Swell (5 division) or without the solo (4 division). Each division will include a quantity of stops (Voices) and depending on design of the console / maker) for the genuine pump blown consoles which were electrified from the 70’s onwards with complex hydraulic systems with controllers) a console would have a panel above manuals for couplers, tremulant or tremulants, particular functions such as tremulant speeds, etc. Under each manual, a set of Pistons, these are a combination of Divisional Pistons for each manual and depending on console design, also General Pistons which store the entire organ’s settings to recall.
Now, with this in mind of a mechanical action console (regardless of the mechanical specification used), when you recall using divisional pistons for a particular manual, that stored function then via a process control system instructs particular stops, couplers, etc to move to turn on or turn off. Even the General Cancel piston, this instructs the entire console to “Zero Out” aka, all off., so it returns the console to initial state ether when turning the console off ready for the next service, or when setting the console up for another series of stops.
A traditional console where either Draw or tab stops are fitted, is purely tactile, the only functions which don’t themselves have an instant recall due to their very nature, are divisional and general pistons, Gen Cancel, SET and sequencer functions, these are becahse they are purely momentary fnctions as instruction commands only to alter stop and coupler functions. For someone blind, like myself who sees nothing but Pure Black (that would frighten the hell out of anyone), touch is the most vital sense in processing multi-sensory information. For that of an organ, the issue is of when a stop is engaged / disengaged. Referring to the above states, a draw or tab stop console with any form of mechanical action with physical action drive (ability for a stop to be moved by mechanical recall) can be felt easily, But not if the console has “soft” tabs or “Soft” draw stops.
Picture if you will, yourself sat at an organ console, like a Fr. Willis & Sons, or Harrison & Harrison., where you are faced with 4 manuals directly in front of you, to the left you have a large panel in an angle of about 30 degree, this would contain approx 40 physical draw stops. They would be assigned in groups with a 30 degree 1 to 2 row difference in position (Row 1 is at top, row 2 drops down in line with the gap between the two stops distance of row 1), so you can feel where you are in a stop gallery. These concepts weren’t designed for the blind at all, these were designed as far back as the mid 1800’s for certain large format consoles. Each division has a difference in distance known as a split. sighted users will notice that each gallery has a name plat above each stop gallery indicating the division or function array. So, the left Stop Jamb would house the Pedal, solo and either full or half Choir. The right stop jamb described in similar terms would house either. half of the Choir, then Great and Swell divisions, also any Couplers or assignable functions for unique stops which could be routed to different manuals independently… Above the top manual (Swell) you would likely find a panel with a series of front facing tab stops, these are actually a number of function states, not voices or ranks, these would be Couplers, Couplers link manuals to manuals or manuals to pedals. good example, Coupler saying “Pedal to Great” means that when the pedal board is connected to the great, both pedal division stops and Great stops are played by the pedalboard, to Wind blown consoles this comes at the cost of being a Tracker action / Hydraulic action series of keyboards, what this means is, it’s not a simulation, you press a pedal note such as 1st octave D, then the First octagve D of the Great manual is also physically pressed by the pedal. or if you coupled the choir to swell, pressed several keys of the choir, the exact same keys of the swell are also played by physical coupling. Electronic / Digital organs don’t do this, because it’s reliant on electronic instruction such as MIDI, general digital keyboards / manuals don’t have a mechanical coupler action, they are tracker emulation by weight and physical feel of the keys, but not by the purpose of physical coupling. The coupling is digital / electronic and as such means it’s “Virtual” so the coupled keyboard doesn’t physically move, but the sound engine replicates by receiving the midi / CV message and plays the coupled manual’s sound board. Still provides the same basic function, but from an aesthetic principle, doesn’t quite resemble that of a traditional console. To do that means electro=mechanical UHT keyboards which are hellishly expensive, further power raills, etc.
Each manual will have underneath, a series of pistons, as discussed, these are either General Pistons or divisional pistons. there may also be dependent on the design / electrifications of the console, sequencer functions such as SET and div cancel (divisional cancel per manual) or General Cancel to the lowest manual usually to the right.
Under the manuals, depending on console design, there may likely be “toe Studs” as well as expression pedals. Expressions cover 2 functions, Crescendo which turns on each stop as programmed by the organ builder in conjunction with an organist when commissioned, (when the crescendo is off - showing up - then any of the stops pulled out for each manual are in use, as the pedal is pressed to move down, further stops are added to each division to expand the sound, to near a full “TUTTI”, when brought back to "off state, the previous stops are back to their state) Consoles are designed differently depending on needs at the time of installation / commission including what expression pedals are added, such as Swell, Choir, Solo, these operate louvre panels within the pipe galleries to enclose (soften) particular divisions, or to open out and let the particular galleries speak out, which is part of the performance of a pipe organ, same goes for a digital console / hauptwerk system, etc. Toe studs are functional pistons either as divisional pistons for the pedal, couplers for pedal, sequencer, etc. For a blind person they’re an interesting experience as you’ll hear now lol.
As an organist, if I turn up at a church I’m booked for, it’s a new console I’ve not worked with before, I have to feel my way around the console. the hardest challenge is knowing what stops are available, couplers, etc. so it boils to two things, either A: if there’s someone there sighted who can provide a read out of each function, they don’t have to understand them just speak out as I then remember the functions, or if engraved, I feel them. now, here’s the laugh of it. Toe Studs… As the name suggests they are at the bottom, away from the pedal board, about 8" away from the raised flat / sharp keys, either side of the expression pedals. Either I run the console and explore it that way, or if there isn’t time, then, I do this… balance myself so that my stomach is on the organ bench, so you basically notice a “bum” in the air, maybe feet also. and my hands feeling positions of toe studs and feeling the inscriptions if there are any. This happened at a cathedral I started working with many years ago, the Priest who only just got to know me, didn’t understand blindness, nor have a single clue of how to support me, so I had to educate him, officially. I was unaware of the fact he was in the building until I heard footsteps closer and closer, as I’m actually doing this very act, this was the first day of my appointment so needed to know the console inside out and couldn’t find someone to be my eyes. “Good heans, What is it that you’re doing?! How unbecoming of someone!”. So, I slid back, turned my head in the sound of his direction. “Sorry Father, just touching up the organ.” “Don’t worry, I’m trying to ascertain what toe studs are what functions, new console to me.”
He didn’t understand until he saw the white cane on the floor. then explained that I am fully blind, seeing nothing but black, this is a new console build to me compared to where I usually work and I need to know what functions are available to me to really make this console sing… So, after that, he stood there as I went through the start of a stop list for notes, then once I found my feet, went through a performance, bringing the console to TUTTI slowly and stunned him, he never had an organist as daring as me.
Now then, back to my point. I’ve described this to you to picture in your mind, the physical layout of a console, now think of yourself surrounded by absolute black, you can’t escape it. Then think “How do I play this organ, I don’t know where the stops are, pistons, etc.” It’s all by feel, the best interaction possible. takes time to learn playing a piano or organ blind, it’s not just the sound, it’s the tactile response and engagement.
All this talk of vibra-capacitive switches, etc, isn’t a source of help inn design. switches like these don’t help in a console design. Why, Think of the stop layout, think of a console with total of over 100 physical stops spread over 2 jambs (left and right). To do this using these switches means that each stop you’d have to rest your finger on to rely on a pulse to state active / inactive, do that over 100 stops, you’d be absolutely confused as heck. Lit switches are fine for someone with sight impairment as they still have light dependency, I don’t.
There are two viable solutions which are viable. this comes from me in a professional capacity as well as that of a blind person and musician, so I’m saying it clearly and happily, with pride.
Solution 1: a hard-wired set of jambs with tactile switches with a physical recall, when the switch is in (pressed in) it’s off, like a normal console would be. when the switch is raised, it’s on. so a square or round momentary type but would need solenoids to drive the buttons to raise / lower for stop recall. I have spent a lot of time trying to find such a solution without luck.
2: Custom Control Surface via Yaeltex. System is fully programmable and designable to particular requirements. Large buttons of different designs can be used. Limitations of the design are that the buttons are lit buttons and “soft” buttons, but they are programmable RGB for sight impaired users and light can be disabled to my understanding if a function is off, so a light scanning tool could be used. The other way of light translation is temperature based, no fancy tools, just how your skin responds to surface temperature and change of, your skin also responds to light as light emits radiation in various levels, so the skin translates this, to some people, it’s a good response. for a blind user, this would rely on adaptation of the host software to speak a function enable, etc and rely on tactile memory when using the system
3: Touch Screen Operation. Touch screens are being used by the blind community through products based on Android, Linux and MacOS, as well as Windows. Screen reader systems are developed now to support touch screen technologies. Take a look at your Apple iPhone or iPad as an example. VoiceOver is actually embedded into the OS by default and ready to use. it adds a touch layer to the OS fundementals and as such adds further functions for the blind. A sighted user just presses once for an app to open or a function to activate / deactivate, single finger glide to change a parameter value such as a slider / rotor, etc. for a screen reader to provide the degree of accessibility to a touch environment means a layer addition and change of gestures. so, an example you want to know where your finger is on a touch screen, press once while the screen reader is running and it will inform you if you are on an app, parameter, text entry, etc, if there’s nothing there directly under your finger, a small sound effect plays, depending on configuration state of the screen reader’s parameters. to engage, such as to turn a function on / off or launch an app, you double tap. it announces the state or opening of a function / app, etc. there are various gestures which are spoken to provide such parameter changes.
Now then, These 3 systems are all perfectly viable. and have their strengths and weaknesses. Option 1 does not require any form of screen reader functionality as it’s purely tactile and that’s the most vital. using anything like a vibrative button interface causes delays in translating what’s there and instant confusion. you want to glide your fingers across or down a surface and know a button is raised or not, not have to rely on a delay action vibration, etc when you’re running multiple stops per manual.
Touch screen interaction will require the host OS with the computer such as a Pi or NUC / USFF system running the OS in question and it’s products in conjunction with either a screen reader running and a series of optimisations of the app in question, or a speech UI that works in the same basic function of the screen reader, but is just purely focused on button engagement / disengagement. This works great with a touch screen based environment as confirmation of such details is there. A script could be created to give a running list of stops engaged, such as “GREAT: Plenim 8’, Bourdon 16’ etc ON” that would be more than enough to provide a great level of accessibility. all that takes is a few seconds of speech out, to the system output of the SBC (computer host) to an earbud. simple as that.
lew
Hi Lew, thanks for the detailed description of organ designs and the challenges you may face. You have mentioned a delay in perceiving a vibration from each physical switch but what about speech / sound feedback as I suggested? You have explained that a screen reader is an acceptable solution which gives audible feedback of status based on touch, i.e. physical position of finger. What if a similar feedback were provided from physical non-latching push buttons? A sighted user could see the state of the buttons from LED indication. An acutely touch sensitive user may be able to determine state by temperature. A blind user would have the state uttered when a button is touched. If lingered they would hear the button’s function which may allow registration of position and also learning layout. This would provide a hybrid of the touchscreen interface you describe and a physical and hence tactile interface. I believe pursuing full emulation of an existing physical organ would be prohibitively expensive. This hybrid may allow an affordable and effective interface.
A good idea, but the issue is not necessarily when a stop is engaged by the user, but when using pistons to recall. so, a good example would be this…
Say on the great manual, you use a divisional piston below the great manual which has a number of stops saved to that particular piston button, say, a good example being Principal 16’, Principal 8’ and flute 4’. in a normal case, the stops physically recall, so on either a tab or draw stop console where the tabs or stops have actuators to physically move the stops, then you’d physically feel whether the stops were out or down. (out for draw stops, down for tab stops). that’s where the issue of recalls comes in. If you weren’t using the sequencer (piston recall for both general and divisional pistons - known as a stop registration sequencer) and you were just setting up your own stops, then you could use normal momentary switches as long as you knew what your stop list was.
One of the things behind software based organs, such as Hauptwerk, Organteq and now Aeolus, regardless of the technologies used, they have what’s classed as “dynamic stops” they’re not fixed. so you could as an example with Aeolus or Organteq, change the stops to suit per manual. With Hauptwerk the stops are changed if you switch sample libraries only, not a user configurable stop list unlike Aeolus and Organteq. So, you’d need to know your stop list as to available stop specifications. This includes stop name and size (not memory) of pipe, hence the above reference to a principal 16’ and 8’ being 16ft and 8ft. if you’ve programmed the console voicing yourself then you’d know what your stop lists are, but if you haven’t, or someone else came to use a setup like this, they wouldn’t know, hence if a console is a static stop list, the details of each stop are engraved to tabs or draw stops for the sighted user. braille isn’t viable because you can’t braille mark a 32mm stop, etc. nor suitable markings on 18mm piston buttons, the viability is memory based (user practice)
One way around something could be a standard panel (momentary switches, but to indicate active stops, then a micro actuator with say a small diameter rod could move out, so that it could be felt. the issue there is that in order to do something like that, the motorised rod would have to be within immediate placement of the momentary switch, which itself would be a flush switch, then the raised rod could then be noticed. I’ve been thinking of different scenarios, but each scenario ccomes up with issues like existing components, pricing factors, etc.
lew
I still don’t know what your opinion is for having physical push buttons that may be assigned by the software and give audible feedback of their state and function.
it’s doable and would be viable. a tone however won’t help because while you’re playing, a tone will distract you, especially when playing complex pieces, so spoken feedback is the best route.
lew
Something like: as soon as a button is touched a voice says, “On” or “Off” or some similar indication. Holding e finger on the button without depressing it continues to say it’s function, e.g. “Flute 4’”. Releasing the button stops announcement. Depressing button toggles or triggers function and announces new state. If finger liners then the function is announced.
something more on the lines of
Stop Button press = “N” on.
Stop Button press = “N” off.
General Piston Button Press = “(Announce Division + enabled stops. - announce division + enabled stops) - (Announce stop name per division) “Gen Piston 1. Pedal: Bourdon 16, Sub Octave. Choir: Nazard 8, Trumpet 8, Great: Principal 16, Principal 8, Trumpet 8, Swell: Stopped Diapason 16, Voix Celest 8, Tremulant ON.”
Divisional Piston Button Press = “(Announce Division + enabled stops) “Choir: Flute 8, Diapason 4, Fifteenth”
If a “SET” button is available to the console, then rather than announce “SET, this should be an audible tone as the button would be held while pressing either a divisional or general piston assignable button. then released… Gen Cancel does not need announcement, but a tone, as the entire console then resets upon press so no stops are active
The only time a console would enable stops other than by divisional or general pistons or by manually enabling stops, is if the crescendo pedal is programmed to turn on a series of stops from at least value 10 to 127 within the midi range of that particular potentiometer. there’s no need for that to be spoken as the crescendo is only programmed based on the stop list from the end user’s needs. so once the end user knows what stops engage per division and at what point within the crescendo potentiometer’s range, then there’s no change in the configuration from that point. The only time that changes is once the end user changes those specifications, such as that of Organteq as a prime example.
I hope this gives an idea.
From a touch screen perspective, I would advise similar to the above, but that depends upon how the screen reader engine interprets the touch layer, or if the screen reader isn’t used, then a TTS engine assigned to particular button functions can then utilise similar characteristics to that of the above.
lew
I just ran across a Vitrual Pipe Organ blog that "details my own conversion of a pipe organ console into a smaller, MIDI-enabled console", while I was looking into the ideal of investing in 7 channel surround sound to enhance the listening experience, this might be a sensible addition to a cheap synthesizer instrument, while some control scheme compromises that may not reproduce the layout of an authentic instrument would keep overall cost and complexity to a reasonable level.
Limiting live performance to a pre-programmed collection of settings, being limited to say 100 patch numbers for a give in session. I’m guessing these patches might also remap the 5 manuals of a massive organ to 2 keyboards, perhaps with some splitting.
Patches could be setup in advance where a clunky selection system with latencies would not be a big issue. It’s possible to limit the custom hardware to a single elaborate control with proportional draw control, tactile and voice feedback, etc. that would be switched to one stop at a time during the audition using off the shelf control switch panels, this would lower cost considerably. The more virtual your control system is, the more easily you change the organ choice between sessions.
By the way, the cheapest way to provide the function of the “small diameter rod could move out, so that it could be felt.” previously described, would be small contact with an electrical charge, controled with a simple switching circuit. This would be interesting to test the sensitivity of braille conditioned fingertips. Expanding on how a 9 volt battery can be tested with your tongue, multiple 9 volt batteries can be interlocked in series to add their voltages, a single wire could complete a circuit from your palm and fingertip. This should be a safe experiment with perhaps up to 5 batteries, just don’t puncture the skin. An ac signal would be more readily detected in a real world feedback system than the DC output of a battery. I suppose some research into long tern exposure to low electric current would be wise before actually using such a scheme.
The Pipe Organ in my Living Room :A Lifelong Journey
Pictured is an organ that looks like what yuou would see in a small cathedral, with 3 manuals, and about 70 stops? and 4 expression pedals, as well as pipes in the background. he goes into detail about his amplifier system. The screen for the added hauprwork virtual instrument is the only non traditional element in the photos.
Classic Organ Works “pushing the bounbdries of electronic organs” has some articles on elaborate projects, like the pdf file “C600 Theatre Organ Project Part-3” Google found, One photo shows a Hauptwerk computer screen with some 240 labeled square buttons, and another 65 small round buttons. Apparently the business sells the shell of an organ with keyboards, etc, for use with electronic voicing.
A 2017 classified ad there is selling a Drawknob console for $1000 with 2 x 61 note keyboards, 32 note pedalboard; 13 drawknobs on right jamb, 13 drawknobs on left jamb;
Usual complement of couplers on rocker tablets, and reversible pistons.
Good article, came across it, but not what’s needed lol
How registrations work on a digital organ are as follows:
General Pistons store a “per general piston” scene of the divisions of a console. So, as an example, If you were to create from scratch, a general piston scheme, then you’d set up a physical set of general pistons, ok, good example. 10.
So, for the 10 General pistons for a given Memory, you’d create a setup where the following happens…
Pedal: select stops you want to use.
Solo (Manual 4): as above
Choir: as above
Great: as above
Swell: as above.
So, now you’ve set up your manuals (divisions) including the pedalboard. you now can save this as a “General Piston” button as a Memory within the sequencer. Certain organ manufacturers use different stop capture systems.
Divisional piston Memories are done in the same way and as such are saved as divisional pistons as a bank, same with general pistons, once you have a set of 10 general pistons and created a choice of divisional pistons, there’s your bank for that scene. so that scene contains both general and divisional piston memories.
how you navigate through scenes is through sequencer buttons, so you’ll have preset up / down and bank up / down. you have two other general functions, SET which is designed to write the divisional and general piston settings to a given general or divisional piston button, and General Cancel, which cancels the entire console out, ALL STOPS OFF, resetting the console to zero mode ready for next use.
as a note, Couplers can also be saved in the divisional and general piston data, so if you called up a general piston with particular stops set per manual, you can also have couplers connected to manuals, so, remember I mentioned in my previous large write-up, that a coupler performs the function of linking physical divisions, such as connecting the pedal to the great, well this can be achieved interdepartmentally and as such, depending on coupler reference, you could do this, Pedal - Choir, Pedal - Swell. So that the pedal can play both the Choir and Swell divisions lowest 32 notes (if using a 32 note pedalboard as an example). So, with this, you could also bring some character / colour in to playing the pedal by using the swell and choir expression pedals to change the volume (character) of the divisions, while playing the pedal. you can still play the manual of the swell and choir while using the pedal to play the lower notes of both divisions. this is a perfect example of the diverse nature of the pipe organ.
TUTTI, this is an important function here. as TUTTI turns ALL STOPS to ALL DIVISIONS ON. so, if ever you’ve been to a church / cathedral for a service, then hear the organ build from a rather soft diapason mix, getting stronger, to the full force of those pipes singing in God’s name, then TUTTI brings the entire stop list out for that extremely rich presence, like Widor’s toccata in F where the pedal division brings in a miriad of stops including 32’ bourdon and sub horns, etc to really bring out that ground shaking feel half way through to the end…
The organ isn’t just an instrument consisting of the pedalboard and manuals, part of playing the instrument is the entire console interface, otherwise you’re not being put to work.
your last comment regarding the test, I wouldn’t do, having had a number of neuro strokes in the past, no thanks.
lew 
Lew you may type faster than me, you may not have seen the Classic Organ Works added above.
I just ran across a short article Hauptwerk for the Blind Organist
Using Hauptwerk with a MIDIWorks organ, photos shows a 3 manual organ with a 9x9 button ( Novation Launchpad S 64-Button Controllers) panel (with braille) on each side, there is also a computer keyboard on the left and a 10 key pad on the right, both slide out lengthewise like a drawer. The Jaws Reader mentioned, for those not familier.
An organ Forum thread: Blind organist with a huge challenge…
I noticed one line in the Hauptwerk installation guide:
"On Windows, if you are visually impaired, download the latest Java and tick the “Enable Java Access Bridge” option in the Use the computer without a display section of the Ease of Access Center Windows. (Should you end up with a dedicated mini PC embedded in an organ system)
@lewisalexander2020 your frustration is evident in many of your postings but so too is your desire to achieve something positive. I don’t think many of us are missing your point.
This Zynthian Discourse is usually light-hearted and often meanders around a topic. @MaxMaxis is particularly prone to adding interesting and eclectic content. His research and links often take us far from the topic but add a depth and breadth of information that helps in all sorts of ways including how best not to do something.
The subject matter of this thread has exercised the philanthropic and altruistic aspects of this community whilst still trying to improve Zynthian design to make it more accessible.
You may ultimately find Zynthian to not be appropriate for your use case but if that is the case then I hope you will take with you some of the ideas voiced here. It is all intended with the best will. Even describing things that don’t work can help to expose other ideas that might.
You have mentioned a few dead-ends you have travelled. These are not necessarily a waste of time. They give further insight and are an important part of design. I think many inventors live most of their lives down dead-ends!
The jovial nature of this forum allows members to ebb and flow and sometimes stray from a topic whilst enjoying the discourse. It is actually quite unusual for detailed design discussions to progress for long here! But it does sometimes happen. 
I have taken a particular interest in this topic, not purely with altruistic intent. I have worked in the field of accessibility and am always looking for ways to share my experience and learn more which may improve my employability. (There - I’m not just a nice guy.)
I am not entirely clear what it is you seek. Reading the thread linked by @MaxMaxis which you authored, it seems you were looking to build a specific solution. This current thread seems to be a more generic exploration of how technology might be put to use in some form to benefit all blind church organ players. Inventors tend to look for new or novel solutions, not necessarily configuring existing solutions. Both approaches can give results and both should be considered.
I feel like this post has gotten long and rambling without any of the humour such a monologue deserves but wanted to avoid you thinking we are ignoring your comments. We enjoy learning from your experience and want to share ours which might trigger the spark of inspiration which leads to the next best thing… Or maybe just another dead-end!
heah, sorry about that. I’ll remove my previous response, etc.
lew
Hi @riban,
I don’t have any experience with these motorized faders. When you say that they are prone to failure, what kind of problems do you mean?
It looks like there is a toothed belt that engages with a drive cog on the motor. When the motor is not energised it would spin freely, allowing the slider to be manually adjusted. I guess over time the teeth would wear and the belt might become slack, causing it to slip. Those of us with cassette decks also know that rubber drive belts eventually become brittle and break, so one would want to be able to get replacements as the devices age.
Those motorized mixer sliders sounded prohibitively expensive, but I found the Bourns pro Audio part: PSM Series Motorized Slide Potentiometer costs <$20. And has a 100,000 operation life rating.
A forum discussion.
One payoff from throwing stuff against the wall in this thread was discovering that manufacturer of dual function switches with touch and press actions. I let a couple of university adaptive device designers know about these switches used in some auto dashboard designs, there seemed to be some interest.
Along this line I wrote a little research paper on possible components for ulra cold (-82·C) freezes for vaccine, for the helpfulengineering.org group, that first was addressing the worst case ventilator demand projections exceeding worldwide production, but have since grown to cover many issues. With the US donating 500,000,000 doses of Pfizer to 100 countries, one thought for 3rd world countries is a thermometric stack booster that would be run inside of a conventional freezer.
I’ve got flying faders on the Motor 61. It needs the connected PSU to fly the faders and there are 9 of them. I don’t know what is the maximum number of parameters I’ve ever seen in a GUI, but it must be in the low hundreds or so . . .
As with any number over 20 or so, from the human perspective it comes down to sort order, It’s probably a data in device that provides the widest level of interface, and physically unifies the tally side of the mechanism with a built in value closed loop to boot.
Wether it’s treated as a glorified switch or a parameter based control source it fit’s nicely into the MIDI control space as well.
The other area of concern from the zynthian perspective is the management of lists using this device, how does one deal with several hundred entries in Engine Preset selection under the control of such a device.
Are they reactive enough to quiver under grab/touch to provide a further level of feedback?
Is the next level of zynthian hardware eight or nine flying faders … ? 
A mixer would be an obvious default.
The eight or nine presents an interesting area. ( well to me any way…) .
Engineers would prefer eight but nine seems a better control block as it provides eight channels and a master in the mixer world, 9 draw bars for the Jimmy Smith world and how about a bank of eight controls and one bank selection control in the zynthian world…?
Actually The Motor61 is eight flying faders and one manual fader 
Cheepskates ...
Is the motor61 usb powered? if so then if it’s standard usb 2 connection then it +5v throughout. If however there’s an external PSU, chances are there’s something like a +12v or +15v Rail in use.
Something like Aeolus, the main parameters are user spec, so, depends on how many manuals (divisions / keyboards + pedalboard) you either need or want,
say, 4 manuals (61 note per manual) + Pedalboard. English Spec, say 20 stops for pedal and an average of between 14 and 20 stops per manual as an example, ok, llet’s be funky, 20 stops per manual, so, 5 x 20 = 100 voices or stops.
if you designed a set of 2 panel cheeks, then it would work as a “per board” 50 maximum of these faders in banks of 10. so that’s 5 sets of 10 faders per panel requiring a controller and power rail. then a panel above the top manual for couplers and tremulants. so, 1 bank of 5 faders for tremulant on / off (1 per manual + pedalboard). add a gap, then you do similar for adding couplers. I’d also add a group of 10 faders for tremulant speed and depth, mapped as pedal speed, pedal depth and so on.
I’ll say this. If it was me, and I was able to assemble a custom board or boards, with these faders, this would be the perfect method, the only elements which don’t need anything like that are piston buttons which are general momentary controls, sequencer and Gen Cancel / Tutti / SET. I know that in some people’s eyes, that’s overkill, but that is the perfect tactile indication without the need of a screen reader running, that is emulating a combination of a tab and draw stop method but as 60mm fiders. you replace the fader heads (if they’re not electro-conductive / electro-capacitive) with wooden balls. some can be marked with dimples to indicate certain particular functions, etc.
YOU’RE A FLIPPIN GENIUS AND I LOVE YOU!!! Why haven’t I thought about that, you’ve just really set an idea off. OK now then, how to go about building these panels without the need of PCB’s and loads of bloomin soldering.
lew
so you’d be looking at
Why thank you. Have a nice biscuit.
lol. thank you, you’ve made my day. I’ve trashed my left shoulder and upper arm on friday, been in pain ever since. GP is useless, Farting in tune is more viable than this GP. I’ve been treating this with deep freeze spray, doesn’t work, deep heat spray, works but is losing it’s strength. a bugger as I’m mum’s carer so this is really driving me up the hoop. 3 nights without much sleep.
lew
P.S: biscuits? That’s bloomin odd, I was munching on one as I got the message. SPOOOOOOOOOOOOO-OOOOOOOOOKY!
Odds are we are eating biscuits whilst reading trivial comments.