Oct. 17, 2021

In 1894 the British electrical engineer and organ builder Robert Hope-Jones took out a patent for a new invention which produced qualities of tone he described under the names Diaphone, Diaphonic Diapason. and Diaphonic Horn.
This form of pipe is open at top and of singular construction; its tone is created by pulses or vibrations in its resonator by the rapid motions of a disk-shaped pallet called a clapper (beater) actuated by pipe wind.
The clapper, or beater, is part of an apparatus in the clapper (beater) box, or boot, of the pipe containing an apparatus which is so connected as to admit a regular succession of puffs of compressed air through an orifice and into the air cavity of the resonator above it; the clapper is a disk valve faced with felt and leather which is held against its seat by a spring which simply opens and closes the lower orifice of the pipe acting in the same way as a striking tongue in the cavity of an ordinary reed pipe.
The Diaphone pipe differs from an ordinary striking reed pipe in that it has no tuning wire and is tuned like any other ordinary labial pipe; it also differs in that, within limits, when blown by different pressures of wind, its power and to a lesser extent its quality of its tone may be altered without any change of pitch.
Hope-Jones carefully tuned Diaphones to pitch pipes and varied wind pressure by as much as 800 per cent without being able to detect the slightest variation of pitch; when passed beyond these limits however the Diaphone went out of tune with the pitch pipe.
This is a high pressure stop voiced on 15 inches or more of wind; most commonly the resonator is made of quadrangular wood of inverted pyramidal form but also may be made stout zinc of inverted conical form; the resulting tone is full and commanding, and evidently, by using different wind pressures, it seems that, within limits, just about ANY strength of tone may be obtained from the Diaphone.
In addition, the pitch of the Diaphone may be made to be independent of the period of a resonator; Diaphonic valves have been made to speak with half length tubes, or without any tubes at all.
Hope-Jones was of the opinion that, when properly made, he did not think that Diaphones should fail to wear well; however, bearing in mind the rapidity with which this piece of mechanism has to act to produce a musical tone, one has reason to question its durability and remaining in good working order for any length of time; this has tended to work against a general introduction of the Diaphone.
Hope-Jones first began inserting this stop in the Pedal divisions of the organ at Worcester Cathedral in 1895 and at McEwan Hall in Edinburgh in 1896 where, in both cases, it could be drawn of 32-foot and 16-foot pitch.
NOTE: The Midmer-Losh organ in the Atlantic City Boardwalk Hall auditorium possesses a unique stop in the organ world -- the 64-foot Diaphone-Dulzian in the Right Pedal Division housed in the right stage chamber, one of only two true full length open stops of this grave pitch in the world (the other is the monster 64-foot reed stop labeled Contra Trombone in the Pedal division of the Hill organ in the Town Hall in Sydney, New South Wales); voiced on 35 inches of wind, this Diaphone-Dulzian stop is mitered in its bottom octave with the tops of the resonators pointing forward like an upside down "L", its bottom 22 pipes are of Diaphone construction, and its remaining pipes are striking reeds -- but because of the way these Diaphone pipes are voiced the transition from Diaphone to reed pipes cannot be detected; and, since its very slow and powerful rhythmic vibrations sound like a helicopter circling overhead it is seldom used, but many more organs including the Saint Louis Scottish Rite Cathedral Kimball (See Photos 3) also have a 64-foot stop in their stop list -- these are acoustic fakes however, created by combining a covered stop of 32-foot pitch (often a Contra Bourdon of Tibia Clausa construction) with a 21-1/3-foot extension situated very closeby in the same chamber and standing at the interval of a perfect 5th above it (the extension often formed of less assertive covered pipes of Lieblich Gedeckt tone) which, by generating the differential tone when both are sounded together, gives a faint 64-foot impression.
When the Rudolph Wurlitzer Manufacturing Company of North Tonawanda, New York bought the Hope-Jones firm in 1910 and acquired all of the Hope-Jones machinery, tools, materials, designs, and patents, the Diaphone continued to be constructed and inserted in Wurlitzer organs all through the heyday of the cinema/theatre organ (c.1910-1930) -- primarily at 16-foot and 32-foot pitches in the Pedal and at 16-foot pitch in the main manual.
NOTE: the photo shows the 12 pipes and clapper (beater) boxes of the bottom octave of the 32-foot Diaphone inserted in the 4-manual Wurlitzer theatre pipe organ Op. 558 originally installed in 1922 in Shea's Hippodrome Theatre in Toronto, Ontario, Canada; when Shea's was demolished in 1958 the instrument was moved to Maple Leaf Gardens and then to Casa Loma in 1970 where it remained in storage until its installation was completed in 1974.

Oct. 16, 2021

(con't from Part II)
"The world is king, and, like a king, desires flattery in return for favor; but true art is selfish and perverse -- it will not submit to the mold of flattery."
-- Conversations (March 1820) -- Ludwig van Beethoven

Oct. 16, 2021

Those who have studied extensively the organ scores of Baroque composers are quite used to running across key signatures which at times, compared with the actual key in which the music is meant to sound and our modern way of notating the key of a work, may be lacking a sharp or flat in the key signature.
Baroque pieces scored in the key of g minor, for example, may only show one flat (Bb) in the signature with the composer writing in all the Eb accidentals each time -- other pieces scored in the key of d minor may not show a flat in the signature at all with the composer writing in all the Bb accidentals each time -- and so on.
But ... what in the world is THIS ? ... (photo)
A key signature like this is something an organist also may run across, albeit much less often, in modern musical notation and is called a "custom signature," or "mixed signature."
Actually, this is no printing error -- it's simply the case of a modern composer not writing in any key per se and merely bending the rules of notation to lessen the work involved in writing in all the accidentals each time-- the music simply has a Bb and an F sharp and works as any other signature, i.e., every B is flat unless altered, and every F is sharp unless altered.
On first glance the key signature of this passage suggests g melodic minor but ascending only, since descending g melodic minor would specify an Fnat and Eb.
This signature (photo) isn't an exact fit with any of the modes either -- but if it were so described the mode would be Bb Lydian with an altered (augmented) 5th.
This same opening passage of music, if notated in the anticipated way these days, would be printed in the key of g minor, i.e. with 2 flats in the key signature, and any accidental F sharps, being raised leading tones, would be written in.

Oct. 15, 2021

(con't from Part IX)
Everything in organ playing is balance.
Going without practice isn't good, but staying on the bench and practicing all night long until dawn the next morning isn't good either -- unless, of course, you never want your fingers to get stuck between the sharp keys ever again.

Oct. 14, 2021

By way of review, there is a little more to pipe organ sound than meets the ear ...
Any musical note has 3 basic qualities: a) pitch (frequency), b) timbre (harmonic content), and c) intensity (loudness).
Pitch is easy to explain: today we define middle C on a piano as 261.625 vibrations-per-second (Hertz, or Hz); the lowest note on the organ at 32-foot C is about 16Hz and the highest about 15,800Hz, which is the widest range of any musical instrument.
Timbre describes the quality or color of a sound; an Oboe and a Flute may be playing exactly the same note (pitch) but no one has any trouble distinguishing the two instruments; the tones have vastly different harmonic content -- a harmonic (also known as a harmonic upper partial tone, or overtone) being simply a multiple of a fundamental pitch.
If, for example, the fundamental pitch, or 1st harmonic, is 100Hz, its 2nd harmonic (1st overtone) would be 200Hz, its 3rd harmonic (2nd overtone) is 300Hz, its 4th harmonic (3rd overtone) is 400Hz, and so on.
We find from this that the pitch number of every organ stop represents either a fundamental or a harmonic of a fundamental.
We also note that pure tones (fundamentals only) do not occur in nature; anything vibrating -- a piano string, organ pipe, or whatever -- does so at multiple frequencies; this is a good thing because without harmonics the wondrous variety of the sounds in nature would not exist.
Intensity, or loudness, is also easy to explain: sound travels in pressure waves similar to waves in the ocean; there are big waves having high amplitude, and there are little waves having low amplitude; our ears perceive these differences in amplitude as loudness or softness, respectively.
Careful examination of the sound produced by organ pipes reveals a number of other factors which, although some are small, contribute to that distinctive pipe organ sound.
Firstly, organ pipes do not start to speak instantly (a feature known as attack), nor do they stop speaking instantly (a feature known as decay) -- and different sizes and types of pipes have their own individual speech characteristics; these qualities are collectively called "envelope."
When the valve snaps open under an organ pipe upon a key at the console being depressed the pipe does not initially speak at exactly the proper pitch -- it may overshoot by quite a lot and create a noticeable effect called "chiff."
In certain types of pipes -- a wooden Gedeckt, for example -- this is an endearing quality and helps gives the stop its unique character; all pipes, even reeds, do this to some extent.
While the pipe is settling down to its proper pitch the harmonic content is changing slightly -- these are called "transient harmonics."
One other subtle factor is present in pipe organ sound -- noise.
Wind-blown pipes produce a certain amount of wind noise; one may not be aware of it when listening, but, without the wind, the tone would be lifeless and plastic; again, different types of pipes exhibit differing amounts of noise creation.
So, the pipe organ is like a huge choir of one-note singers -- each pipe produces only one pitch, but it sings its one note in a most individual and sometimes eccentric manner, which is why making an electronic counterfeit having a truly realistic pipe organ sound is literally not as easy as it sounds.