Update: more on portative organs

I just posted this about an image of St Cecilia carrying a three-manual portative organ.

Just in case anybody actually reads this, here's a quick survey of why that image is a bit fanciful!

Portative organs are just what the name suggests: portable, able to be carried about.  There are plenty of old images of portative organs being used during processions and the like (ostensibly to keep singing in pitch), and of course, the instrument is legion in the iconography of St Cecilia.

This is an historical reconstruction of a portative organ.  You'll note that it's pretty small, having a compass of 15 notes.  My guess is that this would be a 1' rank of pipes, meaning that the lowest pitch is roughly equal to the c above middle c on the piano. The keys are very short; you wouldn't be getting into huge amounts of rapid passagework if you had this strapped over your shoulder and without help to pump the bellows on the back of the pipe rack.


Here's a "period image:"

The Ghent Altarpiece contains an image of a larger organ.  The detail in the painting has allowed modern builders to reconstruct the organ pictured there.