Sunday, November 27, 2005

An Atheist Ponders the Pipe Organ, Acoustics, Electronics, etc.

I have nothing on my mind to write about lately, so I'll put out a segment from a diary entry from August of '04. I had spent the day roaming Manhattan and had bought a couple interesting CDs, one of which sent me down this path of contemplation.

...I found an especially intriguing disc of Tournemire played on the new Fisk organ at Oberlin college, an organ which unabashedly copies a Cavaille-Coll instrument. Or, more accurately, is a speculation of what Cavaille-Coll would have built in this case; the Fisk shop had access to resources of the Cavaille-Coll shop and used his pipe scalings and design preferences (layout, wind pressures)and construction techniques and his same basic machinery (i.e. a Barker Lever) and a stop list which reflects C-C’s practices. Very interesting. This Fisk instrument took me by surprise; I had no idea it (Op. 116, installed 2002) even existed. (I'm spending too much time around airplanes.)

But the recording itself then gets on board and goes a step further: they include a bonus disc called “What the Oberlin Fisk would sound like in Chartres Cathedral.” For this second disc, they basically run the data of the original digital recording through an acoustic program which applies the same alterations to the original data as the acoustics of Chartres have been shown by measurement to alter test sounds played there.

I’ll quote from the liner notes:

“Recently, several companies have released a new type of tool for creating virtual acoustics. This new class of computer program takes actual measurements of specific rooms to create mathematical models. Any sound can be given as input to the model, and the model responds as the room’s acoustics do. In this CD, the acoustics of Chartres Cathedral were measured using a tone sweep generator (a device which “sweeps” in pitch up and down in a predictable pattern) played thru three Genelec S30 monitor speakers. The sound was recorded using Danish Pro Audio 4006 omni microphones (the same microphones used to record in Finney Chapel) at a distance of 11 meters. The recording was sampled at 48 kHz per channel using 24-bit words. The difference between the sweep tone (the loudspeakers) and the recording (the microphones) represents what Chartres Cathedral does to a sound in the room. Because both the recording and the sweep tone are represented numerically in the computer, it is relatively straightforward to create an algorithm that represents the transformation of sound. We selected this model in the computer, and gave it the Oberlin recording as a sound source. The result was what the Oberlin organ would sound like if it were in Chartres--almost! To be precise, the result is similar to what the Oberlin organ would sound like if it were placed in Chartres exactly where the loudspeakers were (in the crossing). Added into the result are also the sound of Finney chapel and the inherent distortions of the loudspeakers and measurement microphones.”

He then goes on to talk a bit about numbers--sampling rates, etc.--in the context of crediting modern computing power with the existence of this tool, and says that “for each second of stereo sound, the computer had to generate 38,896,200,000 numbers”!

Talking about exactly what happens in the acoustic of Chartres, the program tells us that the low frequencies are enhanced while higher frequencies are absorbed a bit more, and of course reverberation goes from a couple seconds in Oberlin to 10 seconds at Chartres, which has a more complicated effect than just the sustain of the original sound. The typical powerful French reeds gain in fundamental and lose in rattle, and the ensemble loses some and gains some.

The resulting CD is really interesting, and there is no hint that any processing has occurred. Though it sounds delicious, to my ear it does not sound like any Cavaille-Coll instrument I’m familiar with, which makes one wonder whether A) the original instruments have changed over time or, more likely, B) whether there is some further (probably human) element--voicing or something--which was responsible in part for C-C's sound and which has not been captured by the Fisk shop. And then there is the question of whether the Fisk shop might have voiced the instrument differently or altered the stop list if the organ were intended for Chartres’ acoustic rather than the relative deadness of the Oberlin recital hall. This is probably an important element: the organ was not voiced around this adopted acoustic.

The liner notes express concern that this technology might lead to the accelerated obsolescence of the concert-going experience, or a further dilution of our reverence for fidelity and for live performance, all valid questions, I suppose. For my part, I wonder if digital technology has not finally reached the point where--heresy! Especially coming from me!--the pipe organ is an obsolete relic. This was of course the threatened outcome when the electronic organ was invented, and it has not thus far come to pass--though surely it will eventually. Electronics get better and better, cheaper and cheaper; at some point the collected expertise of a centuries-old industry will fade out and a very few hugely expensive pipe organs will be built as exercises in Nostalgia, like Harley Davidson. The piano has certainly faded in prominence in the past 50 years because of electronics, and the once-booming industry which makes them is but a shadow of its former glory. (Though I should note that several piano manufacturers are still going strong--Steinway, Yamaha, Kawai, several Korean firms.)

I think there are a couple main things keeping the organ alive still. There is the practical matter of the existence of many thousands of instruments, which require players of pointed technical skill, and thus an educational / training structure with deep roots. This is somewhat self-sustaining, since the existence of organs and people to play and maintain them causes new ones to be built. This whole business creates / sustains fans of both the machinery and of the sounds produced. And of course, there is the magic of the sound itself, a complex and highly variable sound covering several octaves beyond the range of a piano keyboard and in many different timbres and covering a huge dynamic range.

I also think there is a sense of history and a conservatism which attend the circumstances where organs are typically installed and used (i.e. churches and universities--organs are all but extinct in public, civic spaces now) which create a resistance to using an undignified modern keyboard as a replacement. Lastly, I would speculate that most electric sound-reproduction systems would have difficulty with really high-quality production of such powerful sounds, especially the low tones. Even a very expensive speaker system, while it might reach the 16-18 hertz range, could not do so very loudly. Speaker cones would be highly challenged to move as much air in a huge cathedral space as the huge blowers moving thru sequoia-sized pipes can do. Low organ bass is as much felt as it is heard, and I think this is what speakers have trouble with unless you have a rock concert setup. (And maybe even then: a bass guitar is an octave or more above organ bass, and bass drums seem not particularly challenging.)

I used to wonder whether we might not eventually be able to simply “create” beef by synthesizing the actual atomic compounds which make up beef (but maybe without so much fat or cholesterol, or with other alterations) or other foods without having to grow them. (Is this like Soylent Green?) I now wonder whether we're not nearing the point where we can easily synthesize whatever sounds we want, even complex ones. And now with this program we can reproduce faithfully even the effects of the space in which the music might have been played. A virtual space, virtual acoustic. I suppose the better analogy is with digital alteration of a photograph, but many scenarios of virtual reality seem to come into play when one contemplates the issues.

But to return to the Cavaille-Coll knock-off above (just like a Tiffany’s bracelet from Chinatown!), one does marvel at the subtlety of things that we attach ourselves to, sometimes passionately. There is a fabulous brashness about the St. Sulpice organ or St. Sernin, Toulouse, which I think contributes to their personalities. To my ear, the hugely brassy, even harsh, reeds play a role, and some of C-C’s upperwork is downright shrill. But there is such a soul in the shrillness, a personality which emerges when one is not so concerned about filing off every rough edge. And that’s what's missing when I hear this Fisk: it sounds like an instrument which has strenuously had anything which might be deemed a defect cleansed from its character. In this it reminds me of the smoothness of a big Aeolian-Skinner. But even the Skinners gained personality by their impossible variety and dynamic range, and by the absolute round, hugeness of some of the open-voiced stops. Both builders had really beautiful individual sounds in their instruments, but the C-C organs have such a compelling tutti.


Heather B. said...

Why is it that even when you have nothing to write about, you find something to write about? where as when I don't have anything to write about, I try to pass off randomly strung together thoughts as an actual entry and call it "writing". And posting a former journal entry would be the equivalent of posting hastily put together explicitives.

wunelle said...

Well, this actually IS a bunch of randomly strung together thoughts ;-)

I have a zillion such diary entries from the past decade, each of which will hit on just the right audience of three people on the planet (unfortunately, it's always a different three!). But that's OK; it's just what struck me today, and I happened to be listening to that disc.

You get brownie points for reading even part of it!