UCDAVIS -- DEPARTMENT OF MUSIC

The Department of Music's "continuo positive" is a small, movable pipe organ with one manual keyboard.  It was made for UC Davis in 1980 by John Brombaugh & Associates, pipe organ builders in Eugene, Oregon.

The instrument is a synthesis of ideas found in small pipe organs of the Renaissance and later periods so it can provide musicians with a wide variety of resources for the many compositions they want to perform.  It has a slider windchest with simple mechanical key and stop action that supplies the wind to three sets of pipes, two of which are made of fine white oak and one of a lead-tin alloy.  They are an Oak Gedackt 8', an Oak Flute 4' and a Principal 2'.  Each register has 51 pipes with a compass from C to d''', thus there are 153 pipes.   

The 8' stop plays at the same pitch as a harpsichord or piano; it has stoppers at the end of its pipes so they need to be only half as long as the more common open pipes, thereby saving space and weight so the organ can be portable.  The 4' stop plays an octave above normal pitch;  its bass and tenor octave pipes are stopped and its treble has tapered, open pipes.  The 2' stop plays two octaves higher than normal so it can complete the "chorus" when played with the other registers.  The sound from the pipes goes outside the white oak case through the oak carvings based on the acanthus leaf treasured by the Greeks.

Although the ancient organs required someone to "pump" the bellows to provide the wind, our instrument has a small electric blower in its base so the player needs no help.   This base weighs less than 50 lbs;  the upper part with windchest, pipes, and keyboard weighs about 125 lbs and has 4 hidden handles so two people can move it easily.  The organ can be transported in a small car or airplane.

Because modern use of a Positive - the ancient name for a small pipe organ - may require it to play at a wide range of pitches from a' 440 Hz down to a' 415 Hz or to the higher a' 460 Hz pitch when used with other instruments tuned in the ancient pitches, the pitch of this instrument may be changed by moving the connections to the windchest valves to a selection of three positions under its keyboard.  The tuning of all pipes may be changed to allow flexibility in the temperament the musicians may choose for their performances.