What type of contacts to add?

[Guest]

I want to add some extra traps, orchestra bells &amp; midi things to a Conn 651.</p>

Since I can't disconnect anything, I'll need to add another contact strip either on top of the keys or below them. Its an analog organ so there are no +12 or other voltage keying contacts I can tie to.
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What is suggested or most commonly done? Some of the choices seem to be *microswitches *optical interrupters *magnetic reeds *magnetic hall effect sensors *or???</p>

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Is positive(old organ type) or negative(typical electronic) keying mostly used?
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Does anyone make add-on contact assemblies?</p>


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