Hi,  Patrick Boeckstijns asked about the Half Duo-Art system.  Assuming
the electric pump in it is probably a "later addition" and it actually
has the half system in it, it would still work on electric but the
theme would play full volume.  It would be the same as playing it by
pedaling flat out without putting the theme expression into the pedals.

The theme holes both still work in a Half Duo-Art , coming on when the
theme "snakebite" passes either of the theme tracker bar holes, and
switching the theme suction level to the side which called for it.

The normal pedal Half Duo-Art only has the four theme tubes (1T, 2T,
4T, and 8T) and the corresponding valve block, accordion and regulator
missing.  The actual "Themodist" part is still there and working.

Peter Coggins
Blue Mtns
Australia