View Full Version : Registration: (de)crescendo on a Cavaillé-Coll

Jan-20-2006, 17:30
Following a suggestion by Thomas in another discussion, I'm starting one here about registration in French symphonic music. For the moment, I just restrict myself to the typical registration for the outer mouvements of symphonies by Widor and Vierne, where indications in the score are usually least explicit.

Widor and Vierne tailored their works to the instruments built by Cavaillé-Coll (some other organ builders of that time, such as Puget or Merklin, used similar tonal designs), so first of all, a few words about the way these instruments were built.

Usually, Cavaillé-Coll (CC for short) built two chests for each division (the chest is the device which conducts the wind into the pipes through "valves" that are linked to the keys of the manuals; see this link (http://fr.wikipedia.org/wiki/Orgue#Le_sommier) for some nice diagrams on the inner architecture of a chest). The first chest contains all lower pitched flue stops, up to 4', whereas the second chest contains all the higher pitched flue stops (including mutations and mixtures) and the reeds. The point is that the stops on the first chest need a lot of wind, but not at high pressure, while those on the second chest need a lesser amount of wind, but at (much) higher pressure. (There are exceptions sometimes: one often sees some 4' flue stops on the second chest, or a soft reed such as the oboe on the first.)

In CC's instruments, reeds always predominate over mixtures (and there are only very few mutations), hence the second chest is usually called the reed chest.

Now remember: you have two chests for each division (for example, an instrument with three manuals and pedal will have eight chests). In addition, the admission of the wind into the reed chests is controlled by a valve that the player can operate from the console with his feet. I've found a nice picture (http://mq.sydneyorgan.com/Organphotos/Rouenped.jpeg) of how this looks like.

<font color="yellow">1. THEORY</font>

As an example, let us take Widor's famous Toccata, from his Symphony #5, on a standard three-manual CC organ (Great-Choir-Swell).
<ul type="square"> At the beginning, you pull all the stops (except some soft reeds like the Voix humaine and undulating stops like Voix céleste or Unda maris), as well as all couplers, you check that the swell box is open, and you activate all the reed chests.
Towards the middle, Widor asks for a diminuendo leading from fff to pp. This is done in stages, as follows:
-shut down the reed chests of Pedal and Great (fff to ff),
-then shut down the reed chest of Choir (ff to f),
-(very important!) keep the reed chest of Swell active at all times,
-close the swell box (f to pp).
The "small" crescendo" in the middle of the pp section should be done by the swell box alone - don't add any stops here.
Of course, the subsequent big crescendo from pp to fff is realized via the reverse operations in reverse order: first open the swell box, then add the Choir reed chest, then the Great and Pedal reed chests.
In some symphonies, Widor and Vierne tell you to add "Anches du Positif" or "Anches du Grand-Orgue" at some point. Literally, this means "Choir reeds" or "Great reeds", but again: it really means you should add all the stops on the division's reed chest (i.e. the actual reeds, plus the mixtures, plus the high pitched flue stops). On a CC organ, you can do this by drawing the corresponding stops in advance, but keeping the chest closed until the "Anches" indication tells you to activate it. You then simply operate the chest valve with your foot, so changes in registration can be done without the help of an assistant.

You may wonder why I insisted, in Widor's Toccata, to keep the Swell reeds going at all times. There are two reasons for this.
<ul type="square"> Their continuous presence insures that the decrescendo from fff to pp, and the subsequent crescendo back to fff, change the sound's intensity, but not its colour (when the Swell reeds are the only ones left, removing them would give you flue stops only - an abrupt change in colour).
When the Swell reeds are present, the action of the swell box is much more effective.
If you can get hold of Ben van Oosten's recording of the Toccata at St-Ouen (published by MDG), listen to it: it's a textbook rendition of the principles I've described here - and very exciting playing, too!

<font color="yellow">2. PRACTICE</font>

Of course, if you play on an organ whose tonal design is different from those of CC, you can't apply all these recipes literally. Even if it's a CC, you have to adapt them to the particular instrument you're playing. But you should still try to render the spirit:
<ul type="square"> a crescendo should be done with the swell box first (the Swell being strongly registered to make this effective), then by adding groups of stops, in stages (if the crescendo is to lead to a tutti)
such additions (or subtractions) of groups of stops should occur on a strong beat
register those (de)crescendi in such a way that the sound's colour remains as constant as possible
the original "CC sound" requires predominance of reeds over mixtures, so if the latter are too sharp, you should consider not using all of them

OK, I'm afraid that's all I have time for today. - Comments are of course welcome!

Jan-20-2006, 19:11

Nice exposition of French Symphonic registrational practice https://www.magle.dk/ubbthreads/images/graemlins/clap.gif https://www.magle.dk/ubbthreads/images/graemlins/clap.gif https://www.magle.dk/ubbthreads/images/graemlins/clap.gif

I think you meant to say *Ventils* - those levers with which you actuate a group of stops that are pre-drawn.

Excellent contribution.


Giovanni https://www.magle.dk/ubbthreads/images/graemlins/tiphat.gif

Thomas Dressler
Jan-20-2006, 19:16
Dear Acc,

What a wonderful description! Thank you for the time spent on a very clear and informative post! Is this the voice of experience? I've been assuming from your English spelling that you're in England, or have learned British English. . . At any rate, if you have had the opportunity to actually play such instruments--how fortunate!

I do agree with you that adapting to non Cavaillé-Coll instruments can be difficult, and for the most part, we here in America have to do this all the time.

The first thing I'd say about that is that to my ears, when I listen to recordings of real CC instruments, such as my favorite recording--a very old recording of Marcel Dupré playing Widor symphonies at St. Sulpice, I believe I hear a difference between using ventils and using our modern combination actions. It seems when you turn on the reed chests, the wind rushes into the chest creating a WOOSH instead of the BLAMM you get when you just turn stops on that are already fully winded. I've never been there to experience this in person, but that's what I think I'm hearing from the recordings. A very exciting effect!

And yes, when adapting to other instrument, mixtures can be really difficult to deal with. The CC organs have a wonderfully rich sound when playing full chords on the full organ high on the keyboards, whereas German Baroque mixtures (or even some Skinner mixtures--I disagree with those who feel Skinners are "Romantic" organs) get really screechy when you do this. Often the reeds don't work the same as in CC organs, too. Your suggestions about keeping the spirit are right on!

A wonderful post, and I hope we can get some similar postings on different registration practices!

Jan-20-2006, 20:30
Dear Tom,

You're onto the exciting effect created by using ventils - the Organ comes alive - takes on a human dimension. The effect is absolutely stunning!!!


Giovanni https://www.magle.dk/ubbthreads/images/graemlins/tiphat.gif

Jan-20-2006, 22:02
Thanks, Tom and Giovanni - I'm glad you find my description useful.

Giovanni, you're right: ventils is the right word, not valves.

Tom, I also have that old Dupré record (the Symphonie Gothique is awesome!), but I didn't notice the "wooosh" effect you mention - I'll have to listen to it again more carefully.

Jan-20-2006, 22:03
Giovanni, the "human dimension" you just mention is reminiscent of why the old CC preferred the Barker lever over electrical action: he said that using the same power source (namely, wind) for the key action as for producing the sound itself gives a greater unity to the instrument. I'm not quite sure what to make of this argument, but it certainly is of an "organic" nature!

It also reminds me of the introduction of Guillou's book "L'orgue: souvenir et avenir", where he describes that when he went up to an organ loft as a young lad, he already had the impression of approaching a living breathing beast, rather than a big machine.

Jan-21-2006, 01:30
Dear Acc,

Hmmm - the Organ as a living, breathing Beast - yes, living and breathing, but a beast? Nahhh!!! I do admit to admiring the art of Jean Guillou - The Complete works of Bach by Guillou are in my CD-Library. I have read through Guillou's tome entitled L'orgue: Souvenir et Avenir but that was at least 15 years ago. Is it still available? I guess I'll have to hunt around on ebay, book antiquariats and elsewhere.


Giovanni https://www.magle.dk/ubbthreads/images/graemlins/wave.gif

Jan-26-2006, 21:30
I'm afraid Guillou's book is out of print. https://www.magle.dk/ubbthreads/images/graemlins/frown.gif

As for the "beast", I'll have to check again his precise wording. Maybe he said "bête", which doesn't have quite the same connotation.

Jan-26-2006, 21:45
Another point I might mention about playing Widor's Toccata (and similar pieces) on a CC. Most of his instruments have a "Great to itself" coupler, which just disconnects that division's manual from the Barker lever, so that the other divisions coupled to it still sound. (In French, this device is usually called "Grand-Orgue sur machine").

So when Widor asks the player to pass from Great to Swell at the end of the central diminuendo, one just has to use this device, without the need to change manuals: just be sure to disengage the Choir to Great coupler at some stage during the diminuendo, and you end up playing on the Great manual, with only the tutti of the Swell sounding (swellbox shut).

This is very handy to keep the perpetuum-mobile-like rythm steady throughout the piece (especially at St-Sulpice, where the Swell was, at that time, on the fifth manual!).

Jan-27-2006, 03:20
That's a good point you bring up about the *Grand-Orgue sur machine*.


Giovanni https://www.magle.dk/ubbthreads/images/graemlins/tiphat.gif

Jan-31-2006, 19:17
Hi Giovanni,

Actually, an obvious question would be: why did CC not install such a "unison off" mechanism on the other manuals?

My guess is that one has to look into his earlier instruments to understand this, such as Saint-Omer Cathedral (which I was lucky enough to try out a few years ago), built in 1855: only the Great division has a Barker lever, so by operating the "unison off" together with the (say) Swell to Great coupler, you can play the Swell division on the Great manual, thus still taking advantage of the Barker.

That might have been the purpose CC had in mind initially - and he then just kept building this device out of mere habit (not unlike the "Pédale d'orage").

But as I said, it's just my guess...

Jan-31-2006, 21:02
Hi acc,

I fully believe that your guesstimation is right on the mark. Depending on budgetary constraints, CC might have proceeded to include more *devices* in his instruments...

That is my humble guesstimation.


Giovanni https://www.magle.dk/ubbthreads/images/graemlins/tiphat.gif