02 March 2011

Urs Langenbacher: Tradition and Applied Physics for the Guitar I

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An interview with Urs Langenbacher

Hajo:
If one regards Urs Langenbacher from the distance, it is noticeable that the guitar seems to be only a by-product of its work. Your name appears on many restorations of historical instruments and you are also building also for lutes.

Urs:
And in addition I share my workshop with the master violin maker Pierre Chaubert. 
My main focus is on the guitar. But for my guitar concept the intensive study of historic and related instruments is of great importance. You become familiar with different sound characteristics and start to realize which factors are causing the difference.


Head stock © Urs Langenbacher

Hajo:
If you consider the construction and building echnique, how do the old instruments work compared to the modern guitar under constructional or in technical terms?

Urs:
Taking a closer look on Viennese instruments from the 19th Century, it is obvious that the surface and the response of the soundboard are generally different from modern instruments. Compared to the modern Spanish guitar, the coupling of the soundboard and body functions on such usually smaller instruments is completely different. I consider myself a traditional guitar maker and build my instruments largely without spectacular details. From the experiences with other instruments and physical and acoustic principles I am particularly concerned about the elaboration of the sounboard as well as their edge suspension.

"zugeschrieben Staufer" 1.Hälfte 19.Jh. Wien © Urs Langenbacher
Hajo:
Physical Acoustics and guitar craftsmanship guitar is a combination that you can not find that often. How much have you been influenced by the study of physics?
Urs:
If the craftsman wants to know how a guitar works it is necessary to care about the basics in physics of the guitar. During a longer stay in England I dedicated my time researching scientific papers in magazines ono stringed instruments. I created an Article Bibliography with over 2000 articles on stringed and plucked instruments and commented them briefly. Reading all the scientific work one recognizes very fast that the plurality of influent factors represent the actual problem. So they necessarily limit the issue closely, and thus reduce the problems. 

An isolated view of individual aspects is useful, in order to understand the influence possibilities of individual components. What is missing with such a viewpoint however is the representation of the network of the relations between individual parameters and components. Thus the results and conclusions of the research beeing done pass the goal. Nevertheless, it seems to me absolutely necessary to deal with this basic knowledge thoroughly. For my opinion it serves me to handle traditions of building classical guitars in a reflected manner. 

The guitar is an excellent example for it that the whole is substantially more than the sum of its individual parts. In former times I was quite keen on collecting building plans and accurat measurments, in order to collect facts. But in the meantime, I think this is no longer of importance. The plan of an old instrument is important information. But the interpretation of its function is only possible only when I have this instrument in my hand and can develop a sense for the quality of the material.

 Renaissancelaute angelehnt an Frei 1530 © Urs Langenbacher
Hajo:
Are there any instruments that had an influenced the sounddesign  of your own guitars?

Urs:
For sure there are some, but they are very different instruments. So e.g. a Garcia of 1912, whose sound took me nearly down. But there were also instruments from  lesser-known guitar makers. Some worked in quite a different way than the one I'm building. I once restored a Legnani model attributed to Staufer, which I found very impressive. Last year I first saw a Pietro Galinotti for the first time, model "Solero" from 1961, built plain and unspectacular and sounded fantastic. Also two Weißgerber guitars affected me with my sound conceptions. These are all completely different instruments, which have their advantages and naturally also weaknesses, which one ignores then gladly.


Hajo: 
Since I did not have the chance to hear these instruments, can you describe the characteristics of these guitars?


Urs:
It's strange: they are often constructed with a simple design and without ornaments. Besides that they are built very light weighted. This reminds me of a Weißgerber (1937), which has for example, absolutely no soundboard decorations. What distinguished these guitars however was a delicate appearance and a good responsiveness. They have a high sensitivity and however a voluminous bass grounded sound at the same time.

 Musikinstrumentenpreis 2008 © Urs Langenbacher

Hajo:
If you have such a sound in mind, is a guitar with these characteristics suitable for many styles of music, or should a guitar sound like a piano, as neutral as possible?
Urs:

No. An instrument with a soft soundboard as I am used to build has its own character, a typical color and warmth. Also on such an instrument one can also draw clear percussive registers. But regarding playing techniques you have  you have to look elsewhere for an instrument with less than mellow character. I build guitars. Even if Smallman guitars fascinate me with their unwillingness to compromise, but this is not my way.

Konzertgitarre eigenes größeres Modell © Urs Langenbacher

Hajo:
Does the guitarist need several guitars nevertheless?
Urs:
Not necessarily. There are instruments that have a large bandwidth. But there are limits. Comparing a low tuned guitar with a lute, problems in the representation of polyphonic music may emerge. On a lute this music workss completely different. Not for nothing is a lutanist busy to damp down notes which are not provided in the score. He wants to keep his music clear, precise and transparent. A lutanist would run into trouble with a  "flabby" guitar. For this task, an instrument with the character of a boy's voice would be better suited. The instrument must not be depending on deep  fundamentals.
Hajo:
In order to be understood we should before we come to your peculiarities in the construction of your guitars, before discussing a few parameters in the assessment of a guitar. What role plays the volume of a guitar?
Urs:

The concept of volume requires a more precise definition: It is not adequate to only use the sound pressure level to describe what a musician interprets as volume is inadequate. More important is the temporal variation of sound pressure level. The subjective volume is not experienced in the high value peak at the beginning but more in the slow decay of the sound pressure level. The subjective loudness, however, can also be enhanced by certain playing techniques. A guitarist with a very sensitive instrument has the ability to use resonances deliberately. He can plug a string and bring with the left hand the sound to the resonance frequency and thus encourage other strings to resonate. He is able to produce a sustained resonance wave targeted in time, in which this tone stays a lot longer and thus can appear subjectively louder.
Hajo:
How should an envelope for the sound pressure look like ideally?
Urs:

That depends on the preferences and the way the guitar player plays his instrument. An instrument, whose initial peak is very high but caused by the initially increased height looses its power very fast, usually sounds quite hectic. I can imagine that a guitarist can also need such an instrument. Some tremolo passages could be presented with such an instrument more lively, faster or more aggressive. In my opinion however it does not depend however on this very high initial peak. I would rather take it into account that this peak is smaller and the energy is reduced but stays for a longer time so that  the instrument develops more smoothly.


Hajo:
Your development target is not a volume as large as possible?
Urs:

No. I have no problem with a guitarist working with acoustic amplification. But  it has to be adapted to the room where he plays. When we are talking about a duo with different guitars or other instruments the case is slightly different.  In that case it is the task of the guitarist or the string player to adjust his play to the partner not only musically, but also concerning the volume level.

Modell angelehnt an Jean Voboam 1687 Paris © Urs Langenbacher
Hajo:
What about sustain?
Urs:
The Reverberation has mainly to do with the freedom of the diaphragm and  a controlled energy transition from the string to the soundboard. If the energy is reduced and projected too quickly, it evaporates immediately.  This happens for example when the Helmholtz-resoncance frequency  of the corpus is unfortunately exactly the one of an empty string. The sound is loud, but dies immediately. 

Somewhat simplified the process can be described as follows:  I force the vibrating string through a loosely coupled mass (the bridge with the soundboard), to release its energy over a longer period of time and take the same time the "needle" of the mentioned initial peak. But we must not forget: The player has so many technical options with his style of playing to influence the initial peak and the sustain of the tone.  This influence is greater than what can be constructively achieved e.g. by the change of the mass of the bridge.
Hajo:
Are crisp articulation and sustain possible at the same time ?

Urs:

Yes of course it is of course possible. Generally speaking, if an instrument has a good  response in the high trebles, a crisp articulation is evident. The sound is always clear. Even when playing the lute, you can certainly have a long lingering tone and the selectivity at the same time. May be that I do not achieve the warm, full  mellow sound. But this is based on the fact that the soundboard reacts substantially more rigidly and the material thickness of the soundboard is much weaker compared to most guitars.
Hajo:
Time to put it positively: How does the sound of your ideal guitar look like?


Workshop © Urs Langenbacher

This is the first part of the interview of an updated artikel I wrote several years ago for the german magazine "Gitarre Aktuell", but I thought that the subject is still up to date. 


Here you find the second part!