Whew, I didn't know Themodist regulator types were so varied -- there
sure is plenty of different systems.

Regarding Duo-Arts, I always find it better to simplify it into basic
workings to understand it.  Whether half or full, pedal or electric, the
system is basically a Themodist that has the added luxury of a 16-step
control of both level settings.  The half system just has this 16-step
control on the Accompaniment side or, if related to a Themodist, the
lower, regulated side.

I thought that the spill valve was used to stop excessive loading on
the pump during low playing levels and is also sometimes used for subtle
level changes by opening it when it is not normally called for.  (Isn't
this why sometimes there is Theme intensity holes occurring with no
theme accents on??)

Yes, Julian, my box did have the spring loaded cut-off sliders that
you mention.  The inside of the box needed to be extensively modified to
work the same as a normal full DA box.  I still have the original half
box in my garage as I built the new one out of two old spare half
trashed ones I obtained.

Incidentally, these sliders have to be held to one side on the Half
Duo-Art player to get the expression to work, similar to some of the
Themodists I have seen.

As I play mostly Duo-Art rolls on this player, I have disconnected the
springs and now it's just switch to the left for Duo-Art, the right for
normal rolls and in the middle it can help regulate/bypass the levels
for playing Themodist rolls.  The spoolbox Duo-Art switch just controls
the note/intensities cut-out boxes.

I have lost the ability to override the theme using the pedals (as
Spencer pointed out), but some basic overriding can be done using the
bypass levers that Julian mentions.

I am under the impression that pedal/electric Duo-Art's can't pedal
Duo-Art rolls, similar to a pedal/electric Recordo that I once had.

All of the Themodist players (various brands) that I have seen here
in Australia are like the one you described, Robbie, with an adjustable
Accompaniment level regulator, to one fixed level.  But odd players
always turn up....

Bye
Peter Coggins