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Home > Music > Organs > Brombaugh > From The Builder
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by John Brombaugh, 1997
Discussions about building a special organ for Duke University’s
Memorial Chapel began some 12 years ago. Since the room is relatively
small, the milder sound of the early Italian organ was considered
a most suitable complement to the large Flentrop and Æolian
organs in the main part of the Chapel. Meantone tuning, customary
for organs before the 18th century, would also offer a wider scope
of unusual musical opportunities. To avoid diminishing even further
the limited seating space, the new organ would be placed in a
“swallow’s nest” loft made by the organbuilder
to match the organ case. A contract was signed in the spring of
1991, actual construction began in the Brombaugh shop in the summer
of 1995, and the organ was installed in the Memorial Chapel during
the summer of 1997. The result is a new organ — consisting
of 21 ranks, 23 stops, and some 960 pipes — that may very
well be the only modern example of its type in the Western Hemisphere.
The early Renaissance organs in southern Europe seldom made the
aggressive sounds that became common later in France and Germany.
These organs were remarkably simple compared to their northern
cousins, but (especially in Tuscany) they made a wonderful, sweet
sound. Instruments in Italy seldom had more than one manual keyboard,
and the limited pedals, if present at all, assisted only in playing
occasional bass notes.
Nonetheless, these bass pipes could be quite large, as one can
still see in the 24' front pipes of the Epistle organ in the Basilica
of San Petronio in Bologna. This remarkable instrument, made in
1475 by the renowned Tuscan builder Lorenzo da Prato, has only
about a thousand pipes, but the sound carries softly throughout
the immense church. One of the very few remaining organs from
the 15th century, it underwent a minor renovation in 1532 to accommodate
retuning in meantone temperament. The San Petronio organ —
as well as similar ones by Domenico di Lorenzo in Lucca and Florence,
and by Giovanni Piffero in Siena — was the primary inspiration
for the Principal chorus and two flute stops (4' and 2 2/3') on
the main (Great) division of the Memorial Chapel organ. The Italian
pipes are modeled specifically after still extant examples from
1480, 1551, and 1612.
The Italian Principal chorus, referred to as the ripieno, comprises
several sets of narrow cylindrical metal pipes, of which the visible
front pipes are the largest. The lowest rank of facade pipes (Principale
8') extends from two octaves below middle c to two octaves above
it. Additional stops in the ripieno sound either an octave or
a fifth higher in successively higher registers and can be added
separately in various combinations. The smallest pipe of the highest
rank, producing a pitch sounding four octaves above middle c,
is only 1 1/2" long, approaching the upper limit of normal
human hearing. Consequently, the usual Italian practice was to
“break back” the highest pitches to an octave below,
to avoid pipes that would be too small for practical use. The
Memorial Chapel organ includes a tiratutti pedal to engage the
entire Principal chorus at once, a device that appeared on some
Italian instruments by the turn of the 18th century.
In addition to the Principal chorus and the flutes in the main
division, another stop called a Cornettina (seen in later Venetian
organs) has been included. Containing a tierce, or third-sounding
rank, it can be used for solo melodies in the manner of similar
treble stops found in contemporary French, Germanic, and Iberian
organs.
The Great also has two non-Italian flute stops (16' and 8') and
a German Trumpet 8' to expand the organ’s versatility when
playing literature of other national schools. The Trumpet is divisible
between bass and treble, following a common historic convention
in some instruments. The division is found historically at various
points near the middle of the keyboard, but most commonly between
b and c' or between c' and c#' (the latter a consistent feature
in Iberian organs). The Memorial Chapel organ features a lever
that will allow the organist to select either dividing point.
To make the organ still more flexible for playing a variety of
non-Italian music, a second manual division (in the style of a
small north German Brustwerk) adds four more stops. Of special
interest is the Querpfeiff 2', inspired by an unusual overblowing
flute stop with a similar name in the Schnitger organ of the Jakobikirche
in Hamburg.
The Brustwerk manual has the conventional bass “short octave”
format that was customary in keyboard instruments throughout Europe
before the 18th century. That is, the keys that would appear to
be E, F#, and G# in the lowest octave actually play C, D, and
E respectively. The Great keyboard is similar, except the apparent
F# and G# keys in the bottom octave are “split” to
make those pitches available as well the D and E (an arrangement
referred to as a “broken octave”). The keys on both
manuals reflect the shorter dimensions found in early instruments.
The Pedal keyboard, however, has a different layout, assuming
a format often used by the renowned 17th-century north German
builder Arp Schnitger. This keyboard includes F# and G# in the
bass octave but (like the manuals) not C# and D#. The Pedal plays
three of the Great stops by transmission but has no pipes of its
own.
The tuning system used in the Memorial Chapel organ is meantone,
the accepted standard for keyboard instruments in Europe during
the 16th and 17th centuries. The most distinctive feature of 1/4-comma
meantone temperament is that the eight usable major thirds are
tuned absolutely pure, that is, without the audible “beats”
that characterize all intervals (except the octave) in modern
equal temperament. For long-established acoustical reasons, every
practical tuning system involves a certain quid pro quo; in this
case, tuning some pure intervals creates other unusable intervals,
thus permitting only a limited constellation of keys (corresponding
to those commonly used in the repertoire at the time).
To allow composers and keyboard players to venture beyond the
usual limitations of meantone tuning, a few historic organs had
more than 12 notes per octave, extending the range of tolerable
keys. This transient system usually required double (split) keys
for Eb and G# so that one could also play the enharmonic notes
D# and Ab. To ameliorate this rather curious (and at times awkward)
keyboard design for the player, we developed an unusual (but not
unprecedented) mechanical system for the Memorial Chapel organ
so that one can switch between the enharmonic pitches Eb and D#
or G# and Ab on all keyboards by means of two levers.
The organ case and loft for the Memorial Chapel instrument follow
basic Renaissance architectural styles. The upper case, containing
the pipes of the main division, is based on ancient Italian cases
like the one in the Church of San Bernardino in Verona, as well
as others found in some Tuscan churches. The layout of the front
pipes follows a conventional pattern seen, for example, in the
organ at Santa Maria della Scala in Siena. The facade pipes are
made of an alloy that is over 98% tin, and the pipe mouths are
gilded with 23-carat gold leaf.
Within the case, all the pipes rest on windchests. Although most
historic Italian organ builders used an unusual construction known
as a “spring chest,” the more conventional European
type, the “slider chest,” was occasionally found in
Italy as well. The Memorial Chapel organ employs slider chests,
but the stops operating the Italian registers (located on the
left side of the keydesk) are fashioned after the ancient spring
chest levers.
The wind system includes one large wedge bellows and a small
electric blower (the latter a minor concession to modernity).
The wind pressure is only 47 mm, considerably lower than was common
for northern European organs. The simple tremulant (after Schnitger)
is adjustable in its intensity. Components of the wind system,
as well as the largest bass pipes, are placed in a chamber behind
the organ case, accessible by means of a spiral staircase not
visible to the audience or congregation.
About the Builder
One of the world’s most distinguished active organ builders,
John Brombaugh holds degrees in electrical engineering from the
University of Cincinnati and Cornell University. His intended
career as an engineer took a different turn when he chose to work
as an apprentice for the American organ builders Fritz Noack and
Charles Fisk between 1964 and 1967, followed by a brief period
in Hamburg assisting the German builder Rudolf von Beckerath.
Brombaugh established his own firm in Middletown, Ohio, in 1968,
moving to Eugene, Oregon in 1977. Early in his career, he specialized
in organs patterned after 17th-century north German prototypes,
later broadening his expertise to include larger, more eclectic
instruments, but always adhering to the time-honored classical
principles of organ construction. Brombaugh organs are located
throughout the United States and abroad, among them the meantone
instruments at Oberlin College, Southern College, and the Haga
Church in Gothenburg, Sweden.
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