Converting pneumatic keyboards to MIDI

Hello all,

A local has an old pneumatic organ which they no longer. I am considering getting the keyboard and installing them in my Johannus console (which is nothing more than a MIDI console).

How easy (or difficult) would it be to take those pneumatic transmission keyboards and MIDIize them?

Thank you,

Stephane

Without having any specific details, this recent thread might give you some ideas to pursue.

http://forum.hauptwerk.com/viewtopic.php?f=15&t=15348

Rgds,
Ed

Thank you Ed.

S

I would like to advise that I have devised a key contact system that uses Hall Effect sensors.
This system eliminates the hysteresis effect common with the use of magnetic reed switches and very basic Hall Effect sensing. This system gives 100% reliable keying, with no ‘contact bounce’.

Main features:
1. Easy to fit.
2. Very precise measurement of key position.
3. Can send key-on, key-off and velocity data.
4. Multiple ‘on’ point sensing, providing ‘second touch’ output.
5. Direct MIDI output on Channels 1-16. 
6. Very little wiring. Only 15 wires to encoder plus one 5V DC power cable to first PCB.


Description.
System works utilising Hall Effect sensors
One PCB per octave, top octave has 13 sensors.
Other numbers of keys are possible.
PCB is 30mm wide, which make it easy to fit on any kind of keyboard.
System can ‘sense’ movement in either direction, decreasing or increasing distance of key surface to sensors. Circuit board can be mounted in almost any place on keyboard
Small neodymium magnets 3mm diameter and 1.5mm high are mounted on keys using epoxy glue, super glue or similar. Movement of keys is converted to digital format, with resolution of approx. 0.04mm.
No ‘drilling’ of holes is required for magnet fixing. It is enough to maintain similar distance between sensors and magnets. 
Each printed board (octave) is connected to the encoder with one twisted pair cable. Digital data is converted to MIDI messages. Adjustment of firing point, measurement velocity is possible
Because adjustment of contact is only done digitally it is very easy for complete keyboard or for each key to be ‘adjusted’.
As system can have multiple ‘On’ points and it can detect ‘velocity’ and send ‘second touch’ data.
Tests have shown that in the case of keys with sheet metal frame (covered with plastic, such as found on many commercial keyboards) the magnets will hold their position with their own magnetism.

This new system is about to be fitted on two types of manuals, wood core and metal frame.
I will shortly post further details and photos of a complete keyboards fitted with this system.
For further information please contact:
tomasznowak690@gmail.com
info@pipeorganlogic.com

Most pneumatic actions rely on the "touch box" ( the pneumatic valves at the console end of the action) to provide the return springs for the keyboards. If you want to use a keyboard from a pneumatic action organ, then you need to either fit new springs to the keyboard or retain the touch box to provide the return spring mechanism.

Iain

Yes. I have done this. Getting a convincing touch is the hardest part. It's not easy to re-spring.

Upon getting further information on the console, it says the organ is electropeumatic chests.

In that case, should I assume the issues mentioned about console feel and all that are no longer relevant? And that the console is likely using electrical wiring.

In that case, how easy would you think it would be to incorporate into my console?

Thanks all.

Upon getting further information on the console, it says the organ is electropeumatic chests.

In that case, should I assume the issues mentioned about console feel and all that are no longer relevant? And that the console is likely using electrical wiring.

In that case, how easy would you think it would be to incorporate into my console?

Thanks all.

Not sure what you mean by the organ is electro pneumatic chests. That doesn't directly refer to the console itself. If it did, most likely that would indicate a combination of electric(cal) and pneumatic meaning the console would require both. In that case you would need to supply air by some means, possibly a small blower. Except for tracker organs, the pipe chests are, themselves, electro pneumatic. You still would need more specific info regarding the console as was mentioned above.

I did a "electro pneumatic" console quite a few years ago and basically totally re-built it by replacing the keyboards, pistons and coupler board as well as the expression pedals. Pretty much only the console's housing was used (and even stripped out, it was a heavy beast) that needed to be re-finished as well. In my case, a way too big job I probably would never do again.

Rgds,
Ed

If the key action is electro pneumatic then the keys will have contacts and wire connecting them (eventually) to the electro magnets in the chests. The keys will also be sprung in the keyboard assembly. You should be able to use these keyboards as a part of a midi console build. You will need a suitable midi encoder which supports individual keys.

The stops most likely have magnets to operate them through the piston system though some consoles used pneumatic (wind) for the piston actions even though the stops were electrical switches.

Iain

There is another issue to consider, and this all depends on inspecting the console. In the case I mentioned above, the original keyboards did have wiring, one per key. But the contacts were not able to operate an encoder because they had operated, for a long time, fairly high current chest magnets and had arced so much that even with cleaning were intermittent big time. So it all depends.

Rgds,
Ed

I wonder if De-Oxit Gold would rejuvenate the contacts. I have seen it work on some pretty bad ones, like the Schober spring contacts. With the cost of Fatar manual being around $500/kb, it just depends on whether you want to do all that work or perhaps the organist needs a heavy duty keyboard.

Thomas

Back to my case, which really isn't too unusual when it comes to consoles that had been connected to real pipes. In this case, the metal of the many of the contacts had been displaced. I had a metallurgist examine them (as the client didn't want the added cost of keyboard replacement) and that was his finding. What had been good contact material had turned into a partial semi conducting substance which didn't play the real pipes any longer either. No amount of any contact conditioning substance would have helped. This console was connected to the chest magnets without a relay and thus arced with the heat generated producing the problem. So again, it all depends. Modern pipe playing organ consoles don't have this issue as the key contacts are driving electronics, many times using either MIDI or another similar format connected to encoders just as we are doing. It's the old (and cheaper) consoles that need to be examined.

I'm not trying to be negative here, maybe a little "gun shy" tho..

BTW, for any who are not familiar with Schober organ consoles, the key contacts didn't drive any current "consuming" components, only electronics, at first vacuum tube circuits, and later solid state devices. The only problem(s) I had with any of my Schobers was the contact actuators tended to age and would break. And they were a "pistol" to change as you had to remove the keyboards in order to pull out the gold plated bus bars first. If you don't know about this setup, feel good about it.

Rgds,
Ed

Back to my case, which really isn't too unusual when it comes to consoles that had been connected to real pipes. In this case, the metal of the many of the contacts had been displaced. I had a metallurgist examine them (as the client didn't want the added cost of keyboard replacement) and that was his finding. What had been good contact material had turned into a partial semi conducting substance which didn't play the real pipes any longer either. No amount of any contact conditioning substance would have helped. This console was connected to the chest magnets without a relay and thus arced with the heat generated producing the problem. So again, it all depends. Modern pipe playing organ consoles don't have this issue as the key contacts are driving electronics, many times using either MIDI or another similar format connected to encoders just as we are doing. It's the old (and cheaper) consoles that need to be examined.

I'm not trying to be negative here, maybe a little "gun shy" tho..

BTW, for any who are not familiar with Schober organ consoles, the key contacts didn't drive any current "consuming" components, only electronics, at first vacuum tube circuits, and later solid state devices. The only problem(s) I had with any of my Schobers was the contact actuators tended to age and would break. And they were a "pistol" to change as you had to remove the keyboards in order to pull out the gold plated bus bars first. If you don't know about this setup, feel good about it.

Although I do not agree with your contact conditioning opinion I will defend until death your right to be wrong

The Schober line is a keeper, as you said.

Thomas



Rgds,
Ed

Although I do not agree with your contact conditioning opinion I will defend until death your right to be wrong

The Schober line is a keeper, as you said.

BTW, Thomas, as a good friend keeps telling me, remember we need to take care of "us" because we are dead for a long time. (Thought about that while visiting my cardiologist today).

For the record, the info/opinion on the contact situation was not mine. We did originally, and with advice from the makers of De-Oxit, attempt to use all of their products (and I still use them). The info came from a metallurgist I happened to know at the time (now deceased). We also sent contact samples to Caig Labs out in California. Their metallurgist agreed with the findings that the contact material had become a non conductor and as they said, beyond conditioning. I even went so far as to see if the contacts could have been replated with no success. So to use a reverse play of words, we left no turn unstoned.

Now my original point is, there is no way, other than inspecting and testing to know for certain if a pipe organ console's contacts could be used to drive an encoder. They may or may not be ok. 'nuff said.

And, yes, I still am a (fond) supporter of the late Richard Dorf. I still look back positively on the experience of getting boxes and cartons in the mail and building a complete Schober organ. His beautiful do-it-yourself consoles are still used by some folks who have replaced the electronics, keyboards, and such. He was a pioneer. Even the bench(es) and pedal boards were well done. I built all the Schober organ models except the smallest split manual spinet. As good as that experience was then, seeing advances with Hauptwerk (along with computers today) I wouldn't go back.

Rgds,
Ed