Downside Abbey

[Rowland Wateridge]

S_L:   This is very helpful!  Thank you.  People should now be able to work out the derivations.

[OwenTurner]

12 hours ago, S_L said:

The independent mutation ranks are of course extended from foundation ranks as well.
Many people could believe such mutation ranks obtained from tempered foundation stops won't work, being off-tune.
But we must take the place of such stops in such a design into account: the Mixtures are there to add sparkle, not to build true choruses, while the Mutation stops are ever soft, intended for synthetic registrations.

Very interesting, thanks S_L. I've never heard of this before. Does it really work? In my experience of the Hammond and its equal temperament 2 2/3, 1 3/5 ad 1 1/3 drawbars I don't think it does. Does it work here or is the ear and brain forever trying to bend it into what it ought to be?, a bit like practising on an out of tune keyboard instrument.

[contraviolone]

13 hours ago, S_L said:

 

This isn't in full by any means - but it may help to work out where things have come from:

 

This organ was build in 1931 by John Compton with 35 ranks, retaining pipes from 11 ancient stops.

At the console this is a big organ with 4 manuals and a floating Bombarde division:

Actually, the organ is entirely enclosed in three Swell boxes, while the true specification is as follows:

Chamber A: Great, Choir and their Pedal basses

Posaune
Tromba
Diapason I
Diapason II
Diapason III
Diapason IV
Salicional
Hohl flute
Flauto traverso
Clarinet
Tierce
Gedeckt
Dulciana
Vox angelica
Celeste
Gemshorn
Diaphone

Chamber B Swell, Solo and their Pedal basses

Trumpet
Hautboy
Horn
Gamba
Geigen
Strings (two ranks)
Violone
Diapason
Stopped Diapason
(Harmonic) flute
Harmonics 4 ranks
(Orchestral) Oboe
Great Flute

Chamber C

Tuba

With this relatively modest, but carefully tought specification, widely duplexed and extended, Compton gave us a splendid organ, which says a lot about the man's
abilities.

Quite surprising is the way the Mixtures are obtained:

-The Great Plein jeu is extended from the four Diapasons and the Gemshorn

-The Great Cymbale from the Salicional and the Gemshorn

-The Swell Cymbale from Gamba, Geigen and Violone

-The Choir Acuta from the Dulciana

-The Choir Petite Cymbale from Diapason III, Salicional and Gemshorn

-The Solo Kalophone from Gamba and Harmonics 4 ranks !

-And the Baryphone from Violone, Harmonic Flute and Harmonics 4 ranks.

The independent mutation ranks are of course extended from foundation ranks as well.
Many people could believe such mutation ranks obtained from tempered foundation stops won't work, being off-tune.
But we must take the place of such stops in such a design into account: the Mixtures are there to add sparkle, not to build true choruses, while the Mutation stops are
ever soft, intended for synthetic registrations.

Accessories

Detached electric console
Double-touch luminous disc stops
Solid state memory to all pistons (this is a later addition)
8 pistons each to Choir, Great, Swell and Solo
8 pistons to Bombarde, 10 to Pedal
8 general pistons
General crescendo Pedal (acting upon) Great and Pedal
Usual couplers including Great to Choir, Bombarde to Great on second touch and
Solo to Choir on second touch.
Sustainers to Choir and Solo
Six Tremulants to different ranks
Wind pressures from 6" to 20"
 

 

And I was led to believe (I forget the source) that it was 38 ranks but only 35 ranks.

Remarkable really how much may be obtained from such a modest number of ranks.

 

[contraviolone]

39 minutes ago, OwenTurner said:

Very interesting, thanks S_L. I've never heard of this before. Does it really work? In my experience of the Hammond and its equal temperament 2 2/3, 1 3/5 ad 1 1/3 drawbars I don't think it does. Does it work here or is the ear and brain forever trying to bend it into what it ought to be?, a bit like practising on an out of tune keyboard instrument.

I'm not sure if it all really works. I would like to hear the organ in person. 

[ajsphead]

Anyone with access to a copy of Laurence Elvin's book Pipes and Actions with find some useful detail about the instrument, written with assistance from Roger Taylor. 

[Tony Newnham]

Regarding mixtures & mutations drawn from parent 8ft ranks, the 5th sounding pitches (2 2/3 etc) are usually tolerable, the difference between ET & the true harmonic pitch being very small.  Tierces and other pitches are a different matter, and probably best used for solo lines, if at all.

One solution I have come across is where the builder has used an independent mild string rank to derive both a Tierce & a Celeste.  The tuning again is a compromise, but it works well enough for the situation.

Sometimes in extension organs, mixtures etc are derived from true-tuned ranks used just for that purpose.  All very interesting solutions to the twin problems of small organs, and large organs in small spaces.

Every Blessing

Tony