The project Sonus paradisi is concerned with recording, documenting and archiving the sound of old and significant church pipe organs in the Czech Republic and in Europe making them available for software samplers like Hauptwerk. In this way,  playable "images" of the original instruments are offered to users. The sound of each individual pipe of a particular instrument is recorded and all these recordings are ordered and stored in a set of audio files with metadata (the sample set) which is available for purchase from this web site. The original recorded audio data are free to consult for all those who want to examine the sound scientifically and who visit our labs in the Czech Republic. We employ a variety of the ambiental recording techniques (based on multi-channel, recently also employing a "sound holography" 3D recording technique especially developed by us to capture the information about the sound of the pipe propagating through the church space) to store all the aspects of the sound being that especially the interactions between the pipes and the original church reverberation (acoustics) - including the differences in the ambient response to the long or short tones, subleties of the start and end of the pipe speech, minor wind oscilations of pipes in the steady state, even slight instabilities of pipes and similar. We believe that all these contribute to the "realism" of the sound. The main purpose is to make the (as much as possible) exact sound image of the current state of instruments and to conserve it for future.

As the consequence of this, the purpose of the project is threefold:

  • documentary: to archive (conserve) the sound of the historical organ for future in the form of digital data.

  • practical: to offer a playable virtual organ in the form of a sample set for the use of organists and other interested personnel. These digital documents are playable for those who want to play such a virtual organ via MIDI capable electronic instruments connected to a PC.

  • popularizing: to awaken the public concern for the historical instrument by means of providing a demo pieces with the organ music on the internet. By creating these digital documents we want to call the public attention to these historical organs and perhaps also to find sponsors for the restoration of them.

Digitizing process details

We use the technique of recording long samples (usually 6-11 seconds per pipe) with the original church ambience. Several different recording techniques are used (from close up recording to multi channel surround). High quality Apogee, AKG, Beyerdynamics, Digidesign, Forssell, R.M.E., Sennheiser, and Schoeps equipment is used for recordings that preserve a high degree of fidelity. In our opinion, the beauty of these instruments consists in their minor irregularities of the sound. Hence, we do our best to preserve all the proprietary quality of each pipe, initial and stopping transients, the fluctuation of the amplitude and the pitch as well as the "noise" accompanying the sound of the pipe, especially that of the air passing through the pipe. In addition to that, we also record the response of the pipes to the wind changes due to tremulants.

In some cases, multiple samples are taken of the same pipe so that the sound is more variant. This we call "multi-sampling" technology. The tracker noise and the blower noise is also reproduced in most cases. Also the "depth" of the instrument (e. g. the space difference between the Great Organ and the Rückpositiv, Oberwerk or similar) has been preserved in the recording. We believe that listening to a recording made with such a "virtual organ" in decent conditions can be really close to the listening to the recordings of the original instrument.

As the extraneous noise and hiss is the biggest problem in sampling, our primary target when creating the sample set is to preserve the original sound as much as possible while removing the disturbing extrinsic noise as much as completely. We developed over the years a dedicated technique (a multi-step procedure) of denoising the samples which we call virtually "noiseless" so that our sample sets have pristine and at the same time very clean and balanced sound. This essentially mean, that you will not be disturbed excessively by hiss when playing the sample set and at the same time you will not get the impression that the sound of the virtual organ is dull or destructed due to over-denoising. (Well, to obtain the best from the samples in this sense, it is necessary to load them at least in 20-bit depth, loading in 16-bit depth will give rise to a digital hiss because of the noise floor of the 16-bit technology.)

The relation of the original instrument and its digital "copy"

A word has to be said of the correlation of the original instrument and its digital "copy", i.e. the sample set derived from it. The digital "copy" of an instrument is in no way a replacement or a substitution of the real instrument. In fact, the relation between the original and the digital is very weak one. The digital is only a model of the original even if it conserves its tonal properties in great detail with a great precision. To put it into philosophical terms, there is a "substantial difference" between the two. Nevertheless, it must be stressed that the technology we use to capture the sound image of the instrument is an advanced one. In fact, human ear usually does not usually recognize the difference between the original recording and the virtual one. At the same time, the high quality sample set is very good presentation of the tonal qualities of the original instrument too. So, the virtual model of the original organ is also very good promotion of the real instrument in the same way as various musical CD recordings.

Over the years, an analogy came to my mind to illustrate the relation of the digital to the original: I am always saying with a strong emphasis that the relation of the original and the digital is similar to a photography compared to the original photographed object. This observation comes from many years of background (not necessarily only from my own experience) of digitizing the cultural heritage of our country which I am involved in the Academy of Sciences of the Czech Republic. It is now widely agreed that the "digital copy" is a different product from the original (historical manuscript, book, sculpture, organ sound...) It is a product of its own. Partially, it is a model which tries to represent faithfully the qualities of the original object and partially it is a "stand alone", independent new product. To speak about the organs only, the sample set producer is always in the temptation and feels the necessity to "improve" the original instrument (the tuning of pipes, voicing problems and errors, bad pipes) so the product then sounds in some ways much better than the original.
On the other hand, there are "dimensions" of the original instrument which are lost for the very nature of the recording. Especially, the sound is due to the finite number of samples and due to the digital regularizations applied always more "polished" and therefore flat than the original. Concerning the ambience, the original sound is also always more vivid. Just imagine that there are many and many positions from which you can record the instrument and none of them can be said "the only right one". Also, observe, that when you are in the church listening to the organ and you are for example walking around the church, or you simply turn your head a bit, the sound perception changes. There is no way how this can be reproduced in fine detail. And still, there are some other details of the real instrument which can consciously be omitted when making the model or which are even better to avoid.

So, even if you can now acquire a sample set of a given instrument, it is by no way comparable to transferring the original instrument into your living room! It is even only very partially true to say that when playing the sample set in your room, you feel like being in the church. This has nothing to do with the capturing technique used, this comes from the very nature of the original and the digital. To put is simply in an example: when you buy a sample set of an Antegnati organ, you will not have the Antegnati instrument at home, you will have just a model of the Antegnati organ at home.

A member of the team for the Documentation and Research of the cultural heritage of the Czech lands of the Academy of Sciences of the Czech republic (Institute for Classical Studies).