Interview with Bruno Decaris ,
Chief architect of Monuments Historiques

So you are going to build a contemporary organ case in a Gothic building. Can you explain us the concept behind that idea?

I guess I should start speaking about the cathedral itself . You say it’s a Gothic architecture, but is it really? It is actually made of a stratification almost ten centuries old, like most churches built at the time. For me, that stratification is part of what makes it interesting. At each period when a question needed answering, it was so with sincerity. That sincerity is about not disguising: not disguising forms, not giving them another appearance than what they really are. Indeed, they must show the truth before everything else. Therefore, if you have to build an organ case in the 21st century, I can’t imagine why you would build an organ case of the 18th century.

Either you restore an organ case, and you respect it as an entity, for its qualities. It’s a restoration, which means it is appreciated as a creation of the 17th or 18th century! Or you build it. Today, building an organ is an amazing thing. It is a synthesis between music, light, architecture etc..., it is a beautiful project. You have to redefine all the basic principles. When you’re building a car these days, you don’t use rays for the wheels and a wooden steering wheel. However our modern cars are at least as good as the ones built fifty or a hundred years ago. Of course this comparison is a bit practical, but I find the notions of car and organ close enough, because both are made of an engine and a body that are complementary.
One day I was working with another organ builder that Pascal Quoirin and I said: “ today, building an organ is like building a Ferrari! At first, you need a very good engine, and then you need a beautiful body to match it.

Today, only craftsmen can build these exceptional cars. With an organ, you also have that problem matching the engine with the body. But while a car is autonomous and goes everywhere, an organ is motionless and it is made for a place in particular.
Therefore, the third parameter that is added when building an organ, is that an organ must be in symbiosis with space by adapting as much to light and to proportions than to sound.
I think that from the moment when you try and answer these questions, the solution comes naturally. And the question of it being contemporary becomes irrelevant: once again, it is obvious that when we create something today, we do it with sincerity, and it is contemporary in essence.

Let us examine, if you want, a more precise problem: the choice of the general shape of the piece of furniture, the materials you use, the colours, the proportions

First, there is a long history of organs in this cathedral. There used to be the Renaissance case, which burnt in 1940, and they thought of rebuilding the organ’s case in the Seventies in a way close to its original shape but still different… So they made a concrete platform which was based on the shape of the Renaissance organ case, butit wasn’t exactly like it since it was made out of concrete. They made a stylistic choice, well I call it stylistic, and it has all the defects of this type of choice. Indeed concrete doesn’t have the sincerity of stone. It has all its weaknesses, that is an ageing which isn’t as splendid as that of stone. It imitates stone, it imitates wood, we don’t know which way to go, the message is not clear. I don’t know under which conditions the order was made, a bad piece of work doesn’t necessarily mean it was done by a bad architect, but that the order was bad instead. It is possible that the question wasn’t asked the right way, as is often the case.

Actually the construction of a case "in order to receive an organ" had been decided and financed by the Ministry for Cultural Affairs at the time (letter from the Ministry for Cultural Affairs, Jacques Duhamel on February 15, 1973 to Mgr Honore).

And at a later stage they wanted to build the organ! They had the base, but they didn’t have the matching head or bust. So when they asked me about the new organ, I immediately challenged the case, which I thought wasn’t adapted to any project today. The case was like a memory which had nothing to do any more with the organ, had no meaning any longer.
So I thought it would be more interesting to look for another form of relation, which was more about proportions, about the way the light would fall on the organ and how it would fit in that space in the western part of the church.

The peculiar aspect of that cathedral is high and narrow: it has a ratio of 1 to 3, and it’s a problem. The nave is long, high, narrow, which means that an organ placed at the end of the nave must be a powerful organ, producing a sound well directed. This is one of the important data. I think that whatever the shape of the instrument, it’s a parameter to which technique must be subjected. The reading, the integration of the instrument are crucial.
I wanted to express verticality, and the case was in the way. I thought it was much more interesting to use the idea of twinge, this kind of Gothic traditional momentum where you find movement, where something is taking off and goes higher and higher at the same time through sound, through light…

When Suger rebuilt Saint Denis, he did it with the idea of a gradual dematerialization of the building. It illustrates the great quest of Gothic architecture. I wouldn’t go so far as to say that this organ is dematerializing, but there is a crescendo, and this crescendo is part of the symbolic system of our cathedral, it remains very significant.
It’s one of the key points. It illustrates the idea of something that was going to slip into this nave and fit in with it proportions, give an ascension. These were one of the directing points behind my thinking.

On top of that, the way the light falls on the organ is also to be taken into consideration.It’s one of the delicate problems we still need to solve!
Especially as far as the relation with the western face and the Rose behind it are concerned.
The first suggestions took account of the Rose and let it show through completely. I thought that the opposite was appropriate,i.e. that the Rose shouldn’t be hidden or occulted, but that it must bring light down onto the organ, it must make it stand out, reveal it by bringing light onto it, while at the same time it didn’t have to be visible. Therefore, the light comes through, but its source isn’t necessarily visible and thus not too bright. An object standing partly against the light will show better volume.

It could have been a problem if the Rose had been a masterpiece, but I don’t think that’s the case.

It is in no way excpetional. It is a Renaissance Rose, with some qualities, but it isn’t particularly exceptional as far as its design, its stereotomy or its stained glasse are concerned…

Thus all did this thinking led to an extremely vertical structure with a cylindrical shape.

This shape is totally new for an organ case, it’s revolutionary!

Yes, that was the difficult part as far as the instrument was concerned : the wind-chests are orthogonal, and therefore entering squares into rounds is never simple. It is true that at first we had done some research in organ culture : we looked at a number instruments in detail, not only the dresser, but also the engine, because you can’t make a body if we don’t take the engine into account. Thus we paid attention to the way the wind-chests were laid out and how the geometry was working. We obviously had to respect a number of points, but we managed to make superimpositions that were thought to be impossible and turned out to be possible thanks to Pascal Quoirin’s curiosity of mind
We had in mind to build an instrument with very compact mechanics, through unusual superimpositions, because we felt that architecture should be respected.

But it is true that we were not sure about how feasible it would be. We were very lucky to work with an organ factor who was both curious and enthusiastic. The organization called AMORCE also helped and agreed with our idea… and the factor decided to give it a try.

It is very lucky, because often relations between an architect and an organ factor are difficult. And we know that you got along very well.

Yes, and it was a great pleasure. I am used to working within a team, and it can go very well, or very bad. These relationships are based on very simple considerations: when competence, respect and esteem are in the equation, things always go well with the people I have esteem for. It was the case with Pascal Quoirin: he is an exceptional professional. Each of us respected the other’s work and suggestions, and that, I think, is extremely pleasant.

We were very touched by the fact that he showed a great broadness of mind, while knowing the technique, and agreed to explore new territories. And that was what we were interested in, as far as we were concerned, i.e. doing what we couldn’t do.

What materials did you use to build the organ?

First it is made of wood, with lamellae-stuck.So it will be essences of wood put together, with metal reinforcements to make it stronger, because it will be really like a building : 21 meters high for 5 meters wide. Indeed, the structure isn’t very stable, it is narrow and high, and thus it requires a strong stabilisation, although I wouldn’t say rigidity. To avoid buckling, we built a whole system of wind-bracing.So that was one of the first constraints.
Wood seems to us to be the traditional material for that instrument, and that is insdisputable… I concede that people build violins out of metal or out of fibreglass, but to have a good case of resonance, we couldn’t find anything better than wood… Maybe a glass organ, actually, would be interesting, I don’t know if anyone has ever tried: but the problem of choosing the right material is first and foremost because of its acoustic quality.
As far as its stability is concerned, of course, there is a more contemporary technique, so to speak, but that remains lamellae-stuck and a traditional frame.

You added a bit of iron in the frame yourself.

We made a mixed structure, simply in order to make sections smaller, lighter, and to keep sections and supports thin etc, in order to avoid a heavy look, the whole idea being above all to express a feeling of lightness.

On top of the cylindrical shape of the organ, its shutters and the way you made them are one of the peculiarities of that organ. In the old organ building, there is a tradition of shutters, but these are generally tall shutters made of two sides which open and close slowly, majestically. The ones you have conceived are very different.

We built them according to tradition : these shutters are a sign for something that works or doesn’t work. They are like open or closed doors: when they open, you know something is going to happen. Besides these shutters are used to regulate the way sound travels, like conches in an auditorium. They will allow sound to be best guided into the nave.
Also, the organ gives not only a performance of music, but also a visual show. These shutters open quite like a magic box: a box from which not only sound comes out, but also a visual movement, out of which one can see a kind of celebration taking place through its painted shutters. These shutters will be sky blue, like moires: when the instrument is open, something happens, and when it closes it’s all quiet again.

They can also be half-open

They can also be half-open, everything is possible.

These shutters look like the ones that are usually placed inside an organ case for expressive swell. The sound level is low when they are closed, and louder when they open. The organist controls them with an expression pedal. Wouldn’t it be possible to envisage a similar use in your organ, which would add an extra innovative aspect.

I don’t know if that’s possible, I’ll leave the initiative to Pascal Quoirin.

How will the shutters be controlled?

We are looking at several possibilties.: either a completely mechanical system by toothed rack, or a hydraulic system. We haven’t decided yet, it would be interesting for the organist to be able to control the opening himself.

You were mentioning the problem of proportions. For medieval architects, it was a fundamental question: they built proportions through the use of geometry, with a ruler and a pair of compasses., they had the golden number, the root of 2, 3… And baroque organ cases are built with the same respect fro proportions. What is your opinion on that point?

It is a crucial point! When we talk about harmonic relations, we found out that some sound harmonic relations are also visual harmonic relations…Reznikov demonstrated it, by creating a resounding sound in Churches that way. I am absolutely convinced, with all the analyses we have conducted in these projects, that they are perfectly proportioned, as far as geometry is concerned. Why is that? I think it is a tradition derived from Plato or Aristotle, that can also be found in Egypt, in Greece, in Rome, and that was very common during the Middle-Ages. Arab geometry is very famous for being subtle, et it is true that our crusades brought improvements to our geometry. Muslims were led to use that geometry, not only because numbers are very important in the three revealed religions, but also because it is the fastest and the most extraordinary abstraction to express an idea: it is understood by a lot of people. And so I think we inherited it as well, and that we have improved our knowledge even more with the Crusades.

Thus, these buildings are perfectly proportioned. They are not proportioned arithmetically, but geometrically. If you place "root of 2" or "root of 3" into arithmetic, you will obtain 1, 414...., 1, 732.., unfinished numbers. Whereas graphically, "root of 2" and "root of 3" are perfectly exact. Therefore, geometry wins over the rest. It is a way of building in a right and convenient way, through ratios. But these ratios are also related to the universe, and it means going from micro to macro dimension to try and try and find the link that connects the building and the world surrounding it. And we’ll be able to do it through these harmonic relations! It is true that the whole medieval measurement system is based on the human scale, with inches and foot, etc: therefore, man projects himself in that building. But he does so because he is made to the image of God. Therefore, that geometry and those proportions found in the human body can also be found in all our buildings up to the end of the 18th century. This stops with the Revolution, the metric system changes everything in conception. It is a non-religious form of measurement, so to speak, it is more thoretical but it isn’t connected to the universe any longer.

Thus, in Evreux’s cathedral, the regulating layout is clear, it is very simple. And we used the proportions of the building in the conception of the organ.

So the proportions of the organ case are those of the cathedral!

Indeed, we used some of the building’s proportions for the organ, absolutely. I am very intrested in that kind of practice. I can’t say I have done it in a very thorough way, but we used some of the main proportions.

When we look at the nave towards the church, it shows.

It is true that a way of integrating an pobject in an old building is to use its conceptual logic. It is much more interesting than to try and imitate a shape. The object will be much more in agreement with the building if one finds the basis of its fundamental conception, rather than tries to imitate shapes that are subjected to current trends. The building’s proportions, however, are not subjected to current trends. For instance, Mozart could not finish the Requiem, so he called Sussmayr and told him: here are the harmonic rules, finish it, and Sussmayr completed the Requiem, and it all went quite well. We try and work in that frame of mind. The continuity might not be striking as far as materials are concerned, but I think there is a resemblance between the existing building and the instrument.

And more practically, as an architect, how do you work? Do you use a ruler and a pair of compasses, like they used to?

We still use the ruler and the pair of compasses, but now we also have a computer that integrates both of these. Architects also use software like AutoCad, etc (Pascal Quoirin has the same software). That kind of software is interesting insofar as they esentially calculate proportions.
Whereas for a time, we used a ruler and a pair of compasses, but because the ruler had graduation marks, people tended to think in terms of centimeters and meters, and then the concept of ratio had disappeared.
Now this system through conception itself and the use of drawing enhances ratios, which makes it all more interesting. We divide in a certain number of parts, we know this part is inside that one, etc…What makes the whole of a conception becomes a mechanical device, because, each part is inscribed in the whole and vice versa.

The acoustic quality of the cathedral is very a very absorbing one. Indeed, because of the materials that were used to build it and of the general shape of the building, a big part of the sound is lost, especially in the lantern tower. The previous organ had been built directly in a platform under the vault, without an organ case: since the sound wasn’t directed anywhere, the acoustics were very poor. From the platform the sound was fine, but at the other end of the church they couldn’t hear anything. Thus, one of the main issues today is to build an organ that will be loud and have good acoustics. You used a louver. More generally, how did you conceive the organ in order for the sound to be well directed into the nave?

I am not an expert in acoustics, but I think in terms of acoustics. I reckon sounds can bounce the same way light does on mirrors, but it is rather complex…Do you know the Sydney Opera House? With that kind of conch? It is true that there is an expressive aspect about the instrument, and a will that the sound that comes out be sent in a particular direction, so that it won’t be lost…The cylindre, by definition, is a centred shape which would send sounds flying all around, if it wasn’t for the shutters: the fact that you can open and direct them turns the instrument into a sort of wall which directs sound back into a given direction.

What is the shape of the bottom?

The bottom inside the organ is flat, which we did on purpose in order to avoid any loss of sound.

How did you design the louver?

The louver is a curve which protects the top of the organ and directs it. The sound coming out of the top will be directed back to a horizontal level instead of hitting the vault.
The louver has an acoustic fonction, but it also plays with the light. The light from the Rose must be reflected, the louver must have a presence, it must be made iridescent by the light.

Hence the small openings that we can see on the drawing…you made changes to the first plans.

Yes, indeed. The project, you will see, is still based on the same principle. But in the detailed project we have particularly made changes to the footbridge which is around the louver, we thought of something a little more baroque.
We still have this crown, but it seemed to us a little rigid: so we changed it and it now looks a bit like a wedding veil. We will add be a kind of draped fabric which will be a little more poetic. This is not very functional any more, we wanted this small footbridge which allows access to the organist to have something a little more sensual about it.

It is from there that all the circular lighting will come.

That’s it!

You are now going to assemble the organ in Pascal Quoirin’s workshop. How are you going to proceed? The workshop isn't as big as the cathedral.

I think that it will be pre-assembled in the workshop, in three separate parts of about 6, 6 and ½ meters, which will then allow transport to the cathedral. The assembling will be done quite quickly. After that the adjustment itself will last another while: it should take more than a month.

We can’t finish this interview without talking the spiritual aspect: you were alluding to it when discussing your search for verticality characteriscally found in gothic style. In a lot of baroque organ cases, the religious presence is figurative, it is expressed through sculpture. Your organ case, however, is entirely abstract, it is made of plays on shapes, lights and colours.
How do you feel the religious aspect in your organ case?

Yes, you’re right, there is no figurative illustration in that organ case. The instrument is stripped to the minimum. It is limited to its basic needs. It draws its sacred aspect more from its proportions and its style than from its decorations. But I was telling you about the wedding veil: there is a very evanescent side to this instrument, we had in mind an aspect almost virginal. But not directly. No figurative decoration is going to express it but this very metal veil drawn across, with its virginal look. The rest is more abstract.

It’s a reference to Notre-Dame (the Virgin Mary). It’s Notre Dame cathedral.

Remarks collected by Guy More and Yves Laot on October 24th, 2001 in the presbytery of Evreux cathedral

Translated by Elise Leclerc