Workshop: Overtones and their influence on the choir sound

(In-house => dates on request)

In this workshop I would like to give choir singers and conductors tools that lead to a homogeneous choir sound and to a reliable, pure intonation. In addition, sound perception and mutual listening will be trained.

The awareness of overtones helps to make the choir sound more homogeneous and fuller, and above all, to improve intonation and stability. You don't need to be a real overtone singer for this, it is enough to develop a more conscious hearing and perception of the overtones, and with this you get better control over the nuances of vocal colours. By choosing the appropriate vocal colours, the correct intonation between the voices can be made much easier. You get a purer, cleaner choral sound with little effort.

What do overtones have to do with choral singing?

Every tone sung by a person contains - without us normally being aware of it - a multitude of overtones in addition to the fundamental tone. This means that it is in reality not just one tone, but a whole, complex chord consisting of up to 70 partials(1). This chord is always in absolutely perfect, pure tuning. It contains the major triad, the natural seventh, the ninth and other intervals.
The overtones are normally not consciously perceived because we usually do not focus our perception on them. Although the overtones arrive in the ear individually, they are then combined by the brain, and we receive, for example, the information "Someone sings a tone at the pitch C, with the vowel O". However, it is relatively easy and quick to change our perception so that we perceive more individual overtones again. In the next step, this new ability to perceive offers us great opportunities to influence the choir sound and intonation.

Vowels control the overtones - Overtones control the vowels

The singer's sound is created in the larynx - along with all the overtones. Here all overtones are equally loud, i.e. they continuously decrease slightly towards the top. This is the "neutral" sound of the voice, but we never hear it in this way. Because before the sound reaches the eardrum of a listener (or fellow singer!), it first passes through the singer's so-called vocal tract, i.e. throat and oral cavity. There the sound is coloured into a so-called vowel. From a physical point of view, this happens by filtering certain frequencies, i.e. by amplifying or damping them through resonance. For each vowel, such as A, E, I, etc., resonance spaces are altered by muscular settings in the vocal tract (tongue, mouth, lips, etc.), thereby amplifying very specific frequencies and damping others.
When the "neutral" sound from the larynx passes through this filter formed in the vocal tract, certain overtones are amplified or attenuated. This effect is subtle but audible, and always occurs when we sing(2). By choosing a specific vowel and automatically amplifying a particular overtone, we can influence two different effects that are crucial for the sound of a choir:

(1) The perfect alignment of the vowel within a group of singers (e.g. within a vocal group, but also across vocal groups). This makes the sound homogeneous and harmonious.
(2) The support of a clean, pure intonation without effort - by skilfully exploiting the natural harmony of the perfectly pure overtone structure contained in our voice.

We practise this in this way:

Step 1: Vowels control the overtones:
In the first step we use the normal German vowels we are all familiar with and "produce" the overtones with them - just as we have always done when we sing different vowels, only with the difference that we learn to consciously hear the overtones more and more from the sound of our voice.
Step 2: Overtones control the vowels
In the second step, we take the opposite approach, i.e. we use the idea of certain overtones and observe which vowels result from them.

Now the choir singers have created the basis, they have learned how to adjust the vowels exactly and align them exactly with each other, and they can subtly emphasize a selected overtone in order to do justice to the harmonic function of a sung note and to enable themselves and the other voices to "lock in" their notes in the chord.


Contents of the workshop:

  • Introduction to the phenomenon of overtones [Lecture]
  • Perception psychology, hearing experiment - learning to hear overtones [Exercise]
  • Controlling your own overtones / Preliminary exercises for overtone singing [Exercise]
  • Demonstration and exercises with the Analyzer
    (Computer program for real-time frequency analysis) [Lecture/Exercise]
  • Phonetics - the Vocal Diagram [lecture]
  • Matching of vowels: In pairs and in groups [Exercise]
  • Further exercises in vocal phonetics [Exercise]
  • Physical acoustics and its relation to music theory:
    The overtone series, structure of our tonal system [lecture]
  • Small Interval Lore - Interval Lore and its Overtone Relationships [Lecture]
  • Singing Pure Intervals [Exercise]
  • Intervals and scales, solmisation with hand signals [Exercise]
  • An experiment: Piano tuning versus overtone tuning [Exercise]
  • Digression: Modern vocal techniques - the DJ filter effect [Exercise]
  • Major and minor [recital/exercise]
  • Application of what has been learned using examples from choral literature [Exercise].


Practical information about the workshop:

  • Duration of the workshop: 1 day (e.g. 9:30 - 12:30 and 14:00 - 17:00)

  • Room: a suitable choir practice room

  • Equipment: video beamer; flipchart; piano or Clavinova


Trainer: Timber A. Hemprich – overtone singer, composer, performer

  • Music studies: Jazz&Pop, as well as music theory and new media at the Stuttgart University of Music

  • Studies in overtone singing and overtone singing pedagogy with Wolfgang Saus

  • Further training: Lichtenberger Method (with Gisela Rohmert), Roy Hart voice work, Estill Voice Training Level 1&2, Touch your Voice (with Christian Zehnder), Voice Balance & Improphysis (with Iris Hammermeister), Private studies in opera singing (with C. Schuhmacher, Opera Heidelberg)

  • Coaching trainings: Coach for The WorkTM (vtw) ; DES-Mentor (Academy for Essential Psychology)

  • Worldwide concert activity, appearances at numerous international festivals (Smart Light Sydney, Collision Festival London, Marina Bay Festival Singapore, Steirischer Herbst Graz, Stuttgarter Jazztage and many more)

  • Commissioned compositions (Expo2000 Hannover, German Maritime Museum Bremerhaven 2019, 200th anniversary of the University of Hohenheim 2018, BUGA Koblenz 2011 etc.)

  • Overtone soloist and choir singer with the European Overtone Choir (EOC) 2018

  • Overtone choir composition for the EOC 2019

  • Foundation of the experimental vocal trio Vocaltribe 2019



1) The number of audible overtones depends mainly on the sung pitch; furthermore, it also depends on the chosen vowel, the degree of closed quotient, etc. With a low bass tone (e.g. "G2") more overtones fall into the audible range than with a high tone from the soprano (e.g. "F5"). Measurements with special measuring microphones have shown that the overtone spectrum of the human voice extends over the audible range into the ultrasonic range.

2) I am talking here about quite normal, natural-sounding vowels, not about the extreme amplification of overtones as is practiced in actual overtone singing. The latter is achieved by extreme, "unnatural" vowels (in the sense of: vowels not found in our European languages), which is not the subject of this workshop.