Properties of a Pipe tone

By pressing a key the recorded sound in the sample with all its properties will sound exactly as the pipe in the church has done. This takes as long as the button is pressed and because the sound was recorded on average ten to fifteen seconds in the sample, it suffices to play a sound. In a pipe the air column will sound as long as the key is pressed, but it makes it floating, there's always some movement. A short or long press of a button on an organ makes the sound different and this difference can also be heard in a Hauptwerk organ.

When you release the key it immediately switches to the end of the sound. The characteristic way in which the pipe stops a sound and the reverberation in the acoustics of the room is set separately in the memory. This part, added to the sound, is called the reverb tail. When the key is released, it is switched inaudible.

          A sample is an identical sound copy of a pipe tone

The samples determine the quality of the sounds that Hauptwerk represent and there are large differences between the providers of sample sets. But even the best sets do not come to an optimal reproduction of the pipe sound, if the samples with the sounds of a large church organ are not perfectly voiced to the dynamics of the small room of the home environment. The Hauptwerk IV Advanced offers the possibility to voice the samples. Thus, the dynamic conditions between the large room of the church and the living room are bridged.

Sounds of Hauptwerk

In the book Sounds of Hauptwerk, I write why the sounds stored in the samples are better represented as original pipe sounds when they are voiced to the organ. The sample set of the historic Coci-Klapmeyer organ in Altenbruch is a good example to explain this voicing. It is not necessary to buy the whole set immediately as there is a free demo at Sonus Paradisi.                                                                              Sonus Paradisi
The style of this organ was determined 500 years ago by the pipes of Johannes Coci. Centuries-old pipes make sounds with a special resonance that never can be aroused by new pipes. Later organ builders added registers that harmonized well with the old pipes. The sounds are perfectly stored in the samples, but to sound exactly the same in the living room, an adjustment is necessary.

The samples contain the loud sounds of the organ in the large church and they must sound at a lower volume in the living room. Lowering does not work on all tones to the same extent. Highs are more weakened than low, powerful sounds of reeds need to be weakened more than the sweet tones of strings and flutes. An adjustment is needed to display the sounds at a low volume in the same proportions as in the church. A sample set whose sounds are well adapted gives the organist the feeling of playing the organ in the church.

Voicing = adjusting
Adjusting the sounds is called voicing, but should not be compared to the voicing of pipes. The sounds of well-voiced pipes are stored in the samples and these need to be adapted to the living room. The book shows the adjustments I've made. By taking that literally it will sound just better, but more importantly the organist hears the effect of changing the sound. He can then decide whether he wants to apply the effect in his own organ more or less. By always comparing the sound per key with the adjacent key and correcting the difference, an even gradient is obtained.

Hauptwerk V  in de praktijk
                                    Evert-Jan van der Leij

The voicing of the pipes is the most beautiful phase of organ construction. Then the sounds will be heard and the goal is achieved. A long way preceded it, with countless parts having to be carefully made. It is a craft on which many books have been written. The Hauptwerk organ is a new way to make pipe sounds audibly and for a living room this organ has great advantages. The organ is based on a completely different technique, but unfortunately there has been not much written about applying that technique.

The program comes with the User Guide that someone with knowledge of the English language can easily read, but it is not always understandable. The people who are so smart that they can invent Hauptwerk are not so smart that they can explain this wonderful system in an understandable way.

Reading the User Guide and then experiment with computers, the Hauptwerk program and audio systems is the only way to find out. Several people manage to achieve their dream organ. However, it is not given to everyone to describe the method followed, so that it becomes clear to others.

Evert-Jan van der Leij has a thorough experience with Hauptwerk. For years he has adequately answered every question at the PCorgan Forum. Not only he does understand all aspects of the system to the finest points, he is like no other able to explain it clearly.
Three years ago, his book Hauptwerk in de praktijk was published in which he meticulously described how installing and configuring had to be carried out in order to make the most of its possibilities.

Just a few months after the release of Hauptwerk 5, he published his second book, an adaptation and extension of his first book: Hauptwerk V in de praktijk. The many new possibilities offered by the system are also described in detail.

To prevent the illegal use of sample sets, the Pace/iLok license system is used. With the clear explanation, anyone can add their new sample sets without any problems.

A difficult subject is the bus system with an almost infinite number of audio channels. Its use requires a lot of insight from the organist, but with the description of Evert-Jan it is excellent to understand, even though because of the many pictures of the screens that emerge. The book gives an all-encompassing description, with which each organist can compose the organ of his preference:
Stereo 2 channels, Surround 4/6 channels or any configuration that will be desired.

How the acoustics can be added to the sounds with Impulse Response will be clear after reading this chapter. As a copy of the acoustics of the church where the sample set is included, it forms a beautiful unit with the sounds. The acoustics can be arranged in length and effectiveness.

Whatever the organist will prefer, the organ only can make it if the technique is applied correctly and for that purpose Evert-Jan van der Leij wrote this book.

In conclusion, I note that a user of Hauptwerk can look forward to a unique book by an expert who not only fully understands his profession, but is also able to explain it crystal clear. No such book has been written in any language. All organs differ because each organist has his or her personal preferences. With this book, everyone can make their own choice. It is an excellent help for the self-builder, but also for the organist who wants to get to know his organ better.    


The sounds are presented with loudspeakers, but here the speaker has a different function than an audio device. The requirement that the loudspeaker should play a wide range of sound evenly is not applicable here.

All sounds can be adjusted separately, so that the organist is able to achieve an even reproduction. With a good sample, there are two microphones at the point where the organist in the church hears them and these sounds are stored.

When the Hauptwerk organ has two loudspeakers on both sides of the organist, he gets the feeling of playing at the console in the church. It makes no sense to use more speakers. However, a second set of speakers can be used to replay the recorded samples with the acoustics at the same time.

Hauptwerk has an extended control panel to insure that each sound can be voiced independently and sounds like the original pipe. This compensates for the deviations in the samples as well as the deviations of the loudspeakers and so it sounds just like the sound of the pipe.

After voicing the speakers and samples form a unit. By replacing the loudspeaker, all sounds have to be voiced again.

Normal loudspeakers with voiced tones produce the same sounds as the pipes.

 Without adjustment, this cannot be achieved
                                  with even the best hi-fi speakers.

Ordering the book

The book has 238 pages in color on A4 format. To be able to use it conveniently, it has a ring band, so it always stays open. The pages are printed on sturdy paper. A very comprehensive index makes searching easy. The language of the book is Dutch. The many images are as you see them on your organ screen.

The book can be ordered by sending an email with the address details to:

hauptwerkbook (at) telfort (point) nl (words replaced by punctuation marks and the e-mail address without spaces).

The book costs € 30.50 and the packaging and shipping costs are € 5.50 for an address in the Netherlands.
For Belgium, shipping costs are € 14.00
For other countries on demand.

Coci - Klapmeyer organ

One of the most beautyful organs is the Coci - Klapmeyer organ in Altenbruch. The metal of a pipe that has produced the same sound for centuries is metallurgical altered. The most beautiful sound is achieved when the pipe is precisely tuned to its original pitch, the resonance is then maximum. It is comparable to the sounds of a Stradivarius. With time and use, the sound matures and gets a special resonance.
The specifics are present in the samples, but because the sounds in the living room sound at a much lower volume, the character needs to be voiced.

The Hauptwerk books are provided free of charge if the applicant mentions two things:
e-mail and the full mailing address. That is not for economic purposes, but because I want to know which people are interested in Hauptwerk. My data can be seen on the page  Contact                                            
                                                                                      Mail naar: John Boersma

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