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Dec 31, 2008



Good Questions.

Re Glassando: they are easy to do, but just not a C-major "white keys" glissando.

On Thummer/jammer (wicki layout) one has, obviously, the ability to do a "glis" of seconds, fifths and fourths, as well as more exotic ones by going getween rows, e.g. straight up (root, 4&5, octave) - this one sounds neat & clean! I haven't tried it (my keys are a bit too stiff), but one could do a straight across wholetone + a fifth (kinda chromatic) too.

Re: portamento (like on a violin?) - you need a jamstick for this.

Re: Key size. on the Janko you need a shape that is easy to find with both the thumb-side and the finger-tips , and a row for the thumb &  seperate a row for the fingers.  My guess is that a 35 mm deep by 22 mm wide key set up.
Note that the chomatone doubles the rows up and makes the keys half as high. 

Re weight: the downweight should be 40-50 grams. This is far more that the weight of the keys. A much more significant problem is leverage effects making the top row require a lot more downweight than the end of the bottom.



Ken, have you figured out a way to execute a glissando/portamento on a Jammer or C-thru or any other instrument with a isomorphic layout?  I've been thinking about how to do it on a original Janko keyboard (not the Chromatone-312 - they seem to have provided a way to execute a chromatic glissando on that thing).  I am still stumped, still trying to imagine how Paul von Janko, Rubenstein or Liszt might have performed it in their time.

On a different note, it seems to me that what are considered "full-sized" white keys come in two lengths - 6" or 5.5".  So I reckon the most Janko rows that can be made out of midi keyboards is four if the keycaps were cut out to 1.5" in length each (or alternatively, 1.5" for the keycaps for the bottom two rows and 1.25" for the top two rows - similar to Paul Hirsch's beanboard design).  Needless to say, this does not allow space for "chromatic glissando" row like the Chromatone's, unless the keys are extended by 1"-1.5" resulting in a length between 6.5" and 7.5".

My concern is that this extra length would translate to extra key weight causing the key to sag or dip.  This would mean having to look into either replacing the springs at the back with ones with higher tensile capacity (thicker springs?) and/or use stabilizing springs underneath the keys.

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