So it’s been a long time coming, but Kerry and I would like to share the outcomes of our research.

Title

Exploring the benefits of the silicone phonation tube for singing teachers and students: an initial study of use over a three-month period.

(keywords: singing, teaching, phonation tube, SOVTE)

 

Abstract 

This study explores the initial introduction and use of a silicone phonation tube with a range of singing students working in one-to-one lessons, and one community ladies’ choir. Existing research suggests that vocalising through a tube into water can help to relax and reduce tension in the voice, allowing a more safe and efficient use of the voice (Sihvo 2017). In this study, a phonation tube was used over a three-month period in lessons and rehearsals and participants were surveyed to explore their experience. The study findings suggest that using a silicone phonation tube in water has significant potential as a tool for use in singing tuition, enabling students to develop greater understanding of the physical aspects of vocal technique and work more effectively and safely as independent learners.

Introduction

As singing teachers working in a range of educational contexts, we are each committed to finding new and effective ways to support the technical, artistic and musical development of our students. We recently explored the use of the phonation tube in a range of vocal lessons to assess the effectiveness of this tool for singing teachers and students. This article presents the background to the study, including the development of the phonation tube as an approach for helping voice-users and its potential for helping with some of the most common concerns for singing teachers and students. We will also present findings from a survey of singing students and singers, completed after the introduction and initial use of the tube in singing lessons and practice sessions. In conclusion, based on the study findings, the article will provide recommendations for the potential use of the tube as a teaching tool for singing teachers and effective practice device for students.

The phonation tube and semi-occluded vocal tract exercises                                                                                                                                             

Phonation into glass resonance tubes was introduced as a form of voice therapy by Professor Antti Sovijarvi at the Department of Phonetics at the University of Helsinki during the 1960’s. Initial research explored the impact of glass tubes with various lengths and diameters on children and adults with a range of voice problems. Sovijarvi (1965) made recommendations concerning the inner diameter and length of the glass tube according to the age and voice type of the patient. These glass resonance tubes were used for the treatment of professional singers and patients suffering from vocal fatigue as well as those suffering from vocal nodules and vocal fold paralysis (Sovijarvi 1977, 1989).

 

This form of device continues to be used in various types of treatment, whether the aim is to achieve a normal well-functioning voice or as Simberg and Laine (2007) suggest, in the case of patients with neurological disorders, to help delay the deterioration of the strength and quality of the voice (2007, p.166).

 

In 2004/05 Marketta Sihvo, a Finnish Voice Therapist working at Tampere University Hospital, researched the effectiveness of a silicone version of the tube, which she called the Lax Vox© in helping referred voice patients recover the use of their voice (Sihvo 2017). In Sihvo’s approach, a length of silicone tube of 35cm with a diameter of around 1cm inserted into a receptacle of water of varying depths, although 3-5cm depth was suggested initially. Patients are encouraged to phonate through the tube, whilst keeping the water bubbling constantly. The device is recommended for those who have existing vocal problems and also for general use in warming up, cooling down and relaxing the voice and also for the prevention of vocal problems and incorrect vocal habits. She also advocates use of the tube to maintain the voice as ‘a functional tool of vocal communication’, and ‘when learning to control your voice and your behaviour’ (2017, p.68). Her work provides a record of improvement and rehabilitation for patients suffering from a range of voice complaints including fatigue and loss, hoarseness, laryngeal sensations, effortful speaking and voice break. While the introduction of a silicone version of the tube can be regarded as a positive development since the tubing is readily available and affordable from hardware stores, is easily stored and reduces the risk of breakage, it is worth noting that Simberg and Laine (2007) suggest that the use of silicone tubing may not be as effective as the glass tube since the material seems to absorb the sound, which they suggest ‘makes the auditory feedback blurred’ (2007, p.169).

In addition to developments around the use of the resonance and phonation tube, a wealth of research has taken place to explore the effectiveness of using semi-occluded vocal tract exercises(SOVTE) in voice training or as part of voice therapy (Simberg and Laine 2007, Titze 2006, Dargin and Searle 2015, Fantini et al. 2017). According to Simberg and Laine (2007), exercises of this kind used in voice therapy can have ‘a positive effect on the voice because they enhance a more efficient and economic voice production’ (2007, p.170).

Titze (2006), explored traditional exercises of this nature used widely by singing teachers, including lip trills and humming in voice training (spoken) and therapy, concluding that ‘a semi-occlusion in the front of the vocal tract (at the lips) heightens source–tract interaction by raising the mean supra-glottal and intra-glottal pressures’ (2006, p.448) Phonating whilst using any exercises where the vocal tract is occluded, practically-speaking, involves a raising of glottal pressures which in turn allows for a more efficient use of the vocal cords.

In a study of voice users by Calvache et al.,(2019 in press) it was concluded that ‘Phonation into a tube submerged deep in water promoted the highest increase in vocal economy’ with the ‘benefits of increased acoustic output, non-proportional increase in vocal folds adduction and an effortless voice production’ (https://www.ncbi.nlm.nih.gov/pubmed/30738783). Most interestingly, perhaps, is that this conclusion was not limited to those with impaired speaking voices, as healthy subjects were also used.  Similarly positive findings are presented by Fantini et al., (2017) in a study of a trained commercial singers who used SOVTE, ‘showing immediate advantageous effects on singing voice of a semi-occluded vocal tract exercise with a ventilation mask in terms of acoustic quality, phonatory comfort, and voice quality perception’ (2017 p.336). The Fantini et al. (2017) research chose a group of singers to establish whether a SOVTE helped the voice immediately after use and did not explore the longer-term effectiveness of this approach.

A recent review by Mendes et al. (2019), concluded that ‘phonation into glass tubes immersed in water, straws, and Lax Vox tubes promoted positive effects on the voices quality in singers, such as more comfortable phonation, better voice projection, and economy in voice emission’ (2019, p. 381.e1). Similar findings were reported by Goncalves et al, (2019), who found that ‘phonation exercise into a silicone tube caused an immediate positive effect on gospel singers’ voice and comfort phonation’ though both the Mendes and Goncalves et al, studies focussed on the immediate impact of such devices rather than potential for use as a tool in singing tuition and practice.

The findings in this study, inspired by existing work around the benefits of SOVTE for singers (Chapman 2012), suggests that the phonation tube can be a useful addition to a singing teacher’s tool kit, as well as a device that can offer its user and observer/teacher significant insights, via bio-feedback into important aspects of fundamental technical issues. The use of the device for student singers and singing teachers can perhaps be further refined, not just to increase voice efficiency but to aid with more intricate issues involving understanding and control over the unseen vocal instrument and supporting respiratory system. As Shewell (2009) describes, teachers ‘encourage clients to listen in a different way, by feeling a sensation. Clients need to ‘tune into’ body or breath, or the link between voice and feeling’ (Shewell 2009, p.20). This study suggests that the phonation tube is a tool which can be useful in relation to the specific technical concerns and issues experienced by singing teachers and students.  

Common technical concerns for singers and singing teachers

It is accepted that as teachers, we are committed to ‘bringing out the best possible voice in a student and to knowing as much as possible about the field’ (Shewell 2009, p.8). The active role of the teacher is central in the process of developing technical skills and understanding in student singers. Rose (1971) highlights the significance of the teaching process, suggesting that ‘knowledge alone is not enough’ and proposing that the teacher must have, ‘the ability to observe, analyse and reject that which does not produce results’ (Rose 1971, p.22).

Fundamental vocal issues highlighted in the literature in this field include efficient breathing, dealing with constriction, register breaks and maximising resonances within the vocal tract. It is generally agreed that effective voice production requires a healthy degree of tension (Shewell 2009). In many vocal pedagogy guides, the skills needed to produce optimum voice, singing or otherwise, are explored in specific order, with a general agreement on those suggested by Houseman in ‘Finding your Voice’ (2002) – body, breath, support, releasing the sound, resonance and articulation.  

Being able to use the full range of voice including high notes is an issue all singing teachers need to address with their students. Husler and Rod-Marling (1976) suggest that the ‘high range is the product of a special co-ordinate action of various muscle-systems’ and ‘a number of actions can easily obstruct it’ (1976, p.104). Rose (1971) also highlights the need for increased tension in the breathing muscles but recognises that the untrained singer ‘rarely increases these tensions sufficiently’ (1971, p.147). Smith and Chipman (2007) also address the technical issues students can experience with singing higher pitches. Here, the pedagogic response is ‘it’s not how high you get- it’s how you get high…without the sensation of resistance, with the air-flow lifting the soft palate… the goal is to get the sensation of free-flowing air’ (2007, p.73-74).

Smith and Chipman also offer the following observation on soft-singing: ‘We learn…and develop a habit of decreasing airflow and increasing tension whenever we sing softly. Unfortunately, decreased airflow and increased tension are the opposite of what we need to do’ (2007, p.73-74). The idea of airflow being essential to producing a tone of quality is backed up by Rose (1971), who proposes that ‘correct breath flow through control of inspiration and expiration’ is necessary in producing a good quality sung note (1971, p.261).

The phonation tube submerged in water provides the opportunity to view the free-flowing air in its flow of bubbles during phonation. The tube inside the mouth around which the lips are required to make a seal for the device to function properly, also provides a basic mouth position which cannot easily be altered and gives enough space ‘to keep the jaw joints relaxed during the exercise’. The fluttering sensation, felt within the cheeks during use, makes for relaxation of the musculature of the mouth and cheeks which can be areas of tension. Using the tube, individuals are able to identify and resolve areas of tension through bio feedback, allowing greater vocal and facial resonance. 

The study

The aim of this study was to explore the potential of the phonation tube as a tool to help singing teachers and students address technical issues in lessons and practice sessions. The key research questions relate to whether students find the device useful and whether they perceive any benefits in their singing as a result of using the tube.

The study involved singing students in a range of teaching contexts where the two researchers are involved as singing teachers, including private students of varying age and ability, students aged 7 – 18 in an independent school, individual singing students in a girls’ grammar school, undergraduate singers in a university music department and members of a local ladies choir. The researchers introduced the device in lessons over a period of three months in Spring 2019, working with a total of 62 individual singing students plus 12 volunteer members of the ladies’ choir.  Singing teachers working in the same institutions also agreed to introduce the device to students during the same period. Participating students received a tube which was used during lessons and were given instructions on its use in independent practice sessions. Each individual was encouraged to practice exercises and sections of repertoire, alternating between singing into the tube (with one end submerged in water) and singing without the device. During lessons the researchers as practitioners demonstrated using the device and observed progress, sharing experiences and feedback with each other during the process. Volunteers from the ladies’ choir were each given a tube and instructed on its use. They were then encouraged to use the device during choir warm ups and in independent practice sessions.

An online survey was designed and distributed to students via email towards the end of the three-month period to address the initial research questions. The survey link was sent directly to older students and choir members (with the appropriate permission from each institution) and via parents to younger participants. The survey asked participants to reflect on their initial impressions of the device, any notable impact from use and the use of the tube in practice. Finally, participants were asked whether they would recommend the device to other singing students / singers. While some questions, such as the age and gender of participants gave a selection of possible responses, the majority allowed for comments to allow greater insights into the experience and perceptions of participants. The survey findings were analysed using comparison and filtering tools to establish general trends and explore the responses of participants where relevant. Where responses were missing the analysis was performed using only existing responses rather than making any attempt to infer or generalize from any missing data.

Ethical issues

The researchers were aware from the outset that their position as teachers in this context could compromise the validity of any findings as the students involved might be unduly influenced by the teaching relationship. Specifically, the student (especially a younger or more impressionable student) may seek to provide a favourable response for the teacher or the response they think is correct, rather than reflecting openly on their own experience and perceptions. It was therefore vital that the survey was anonymous and that the teacher was removed from the completion process. For this reason, the survey was only available to complete online and student participants were reassured that their responses would be anonymous and that all views were valid and vital to the study. Furthermore, the researchers were conscious that as singers and singing teachers, each also working with the device during the period of the study, their perceptions might influence the outcomes of the study. For this reason, the survey design allows each participant to be able to comment, in an attempt to fully represent their voice in the findings rather than the perceptions of the researchers.

Care was taken to ensure the positive experience of participants, specifically in relation to the perception of the project goals as relating to the potential use of the device rather than the ability of the individual student. It was anticipated that some individuals may feel that a less favourable response might imply some lack of progress or practice on their part. Participants were reassured that their perceptions of the phonation tube were the focus of the research rather than their ability or performance and the survey questions focussed on what participants thought of the device rather than on their perceptions of their own singing or progress.

The sample

The survey was sent out to all students using the tube in lessons and rehearsals over the three-month period. There were 43 survey responses in total, of which 84% were female and 16% male students, corresponding with the male / female ratio in singing students involved in the study. The age range is also representative of the sample, with 7 participants from the under 12 age group, 15 aged from 13 to 18, 9 from 19 to 24, 3 from 25 to 50 and 9 aged 51 and over. The age range therefore reflects the various contexts in which the device was introduced.

Participants were asked to identify their level of experience or expertise from three given options. The responses reflect the age range and institutional contexts of the survey as 17 participants identified as beginner singers, 22 as more advanced singers or singing students and 3 as professional voice users. The majority of participants participated in singing lessons and additional singing activities such as choirs and singing groups. While most were introduced to the phonation tube by a singing teacher or choir director, the device was recommended to some by participants in the study and they subsequently volunteered to take the survey.

Using the tube – experience and perceptions

Asked to reflect on their initial impressions of the tube, participants commented that it seemed strange or weird but most were intrigued to explore the possible benefits to their singing. The responses with regard to the experience of using the device in the first session reflect an immediate impact with participants describing ‘immediate freedom in movement and tone’ and ‘a ‘freeness’ and ease in the voice that is otherwise very difficult to recreate’. Participants also describe feeling ‘significant increase in sound production’ and the majority describe experiencing an immediate impact on breath control and projection during the initial use of the device. For some, the introduction of the device was transformative, as described in the following response, ‘I found that the strain I was putting on my voice in order to sing higher notes was reduced and phrases and shapes of the music became easier especially regarding to breathing’. Others describe a physical response as the phonation tube ‘instantly engaged the core area’, helping participants to ‘figure out where to sing from’ and identify what they had been ‘doing wrong for so long’.

Asked whether they have continued to use the device in their practice since the initial introduction, 8 suggested that they use it in every session while 33 respondents indicated that they had used it sometimes or often. Only one participant suggested that they have not used it in practice. Participants suggest that the device is easy to use in practice sessions, with most using it during warm-ups and to work on problematic passages or phrases as described in this participant’s response, ‘It is very easy to use – a tube in a water bottle! In practice I have used the tube to work on reaching higher notes that I normally find difficult to sing. I have also used it to see my breath control – more so the lack of it- as this can be seen in the bubbles that singing into the tube creates’.

With regard to more general impact on the singing voice as a whole, the majority of participants describe improvements, including an increase in tone, sounding ‘richer and stronger’, feeling the breath coming ‘from the stomach area’ and greater freedom across the vocal range. In addition, responses suggest that the device ‘immediately relaxes the tone and helps ease and place the voice’ and is helpful with ‘finding ‘space’ in the upper register and creating a sense of ease in more difficult passages of music’.

41 of the participants suggested that there has been a positive impact on their singing as a result of using the phonation tube with improvements including a clearer, stronger tone, increased support and less strain, a more relaxed sound and more freedom on the whole, especially in the upper register. 40 respondents stated that they planned to continue using the device in their regular practice routine and all 43 participants confirmed that they would recommend the tube to other singing students and singers.

From the teachers’ perspective

The original idea for exploring the phonation tube as a singing teaching tool came from a desire to help students develop a much deeper understanding of the use of relaxation within the vocal mechanism. Existing research had suggested the therapeutic effect upon voices and increased voice quality brought about by increased vocal cord adduction (Mendes et al. 2019, Fantini 2006, Calvache et al. 2019). This study provides new evidence which confirms the benefits of the tube as a tool for singing students, singers and singing teachers.

As a learning tool, it became clear during this study that the tube helped separate the emotional and technical aspects of the singing voice, allowing students to explore the familiar physical act from a different perspective (Shewell 2009). This, in itself, was of enormous benefit as psychological issues can really interfere with the process involved in developing the voice. The novelty of the device helped relax the students and they seemed to enjoy this approach to technical work, engaging with the physical process and encouraged by the increased understanding of breathing through immediate bio-feedback. Using the tube in lessons allowed teacher and student to focus on the technical aspects of voice production in a relaxed and at times fun way while each were aware of the process and of the impact of the device. Once students understood that all postural habits associated with good singing applied, and that the mouth was to remain as relaxed as possible to enable ‘cheek fluttering’, using the device meant that further instruction could be given to develop even more efficient breathing. Furthermore, it was easier to correct errant posture and mouth tension habits because the focus was on the process rather than the product, allowing work on technical issues without the censure of an unpleasant outcome.

Breathing regulation is a potentially difficult area for student singers because until the individual understands the sensations and how to control various parts of the breathing anatomy, it can be a frustrating process which is not necessarily assisted by the audio feed-back gained from singing (Rose 1971, Smith and Chipman 2007). For many participants in this study, the phonation tube helped to identify where and how the breath was being used and enabled student and teacher to assess weaker or in some cases missing aspects of the process.  Students can potentially understand the theory of effective breath control but have little idea about how to affect this in practice and teachers commonly adopt a variety of strategies including imagery to be able to communicate technique, especially with younger singers (Emmons 1988, Peckham 2010). O’Connor (2019) suggests, ‘At first, most vocal students view breath management as a difficult, unnatural activity that they must somehow attempt to do while trying to sing, as though the two are separate tasks that they must train themselves to do simultaneously’, (Singwise 2019). The phonation tube provides immediate bio-feed-back in the production of a steady stream of bubbles, enabling the student to connect the breath and the voice in one physical act. The regulation of breath through the tube creates the correct muscular tension sensations which enable students to discover what they need to do without strain or damage. This in turn means that the student is able to work independently, reinforcing technical work without the assistance of the teacher and constantly developing both technical ability and understanding of the way in which their voice works.

Accessing the upper register and maintaining a consistent tone across the whole vocal range and into the upper voice can be a real concern for students and teachers of singing (Husler and Rod-Marling 1976, Rose 1971, Smith and Chipman 2007).  Sirening (sliding slowly up through the voice to higher pitches) using the device was a particularly helpful exercise in this respect. The use of sirening in combination with the tube is advocated by Sihvo (2017) and is also commonly employed as a warm up strategy by singing teachers, since as Williams (2013) suggests, the ‘higher range can be encouraged with the use of non-singing ‘noises’ such as whooping, wailing, sighing’ (Williams 2013, p.49). The use of sirening in combination with the tube revealed to some students that they often expected the voice to raise in pitch with very little breath support. Because of the tube and water, it was clear to see through the decrease or lack of bubbles in the water the breath that was passing through the vocal mechanism. In some cases, the bubbles completely stopped, showing them that if there was a product, it was produced without the necessary breath. It often came as a surprise that the notes did not function but pointing out the lack of air gave a tangible reason. This aspect of the device as a teaching and learning tool is particularly interesting, since as Kayes (2004) comments ‘during singing it is not always easy to monitor what is happening with the larynx’ (2004, p.18). For some students, the tube provided a real and useful indication of the physical process involved in the form of bio- feedback, and enabled them to monitor and regulate the connection between the breath and the voice whilst singing. As a result, high notes came much more easily through the tube which then gave increased confidence and most, if not all of the students were able to sing higher in their sung voice, as a result of phonating higher in sirens and other exercises though the tube.

One of the most noticeable effects of the use of the tube in almost all students was the immediate difference in the quality of the singing voice after using it for warming up. Voices responded by being more efficiently supported with fuller and better-quality tone in all registers, particularly middle and upper. Williams (2013) identifies inconsistencies in tone as a key area of concern with younger voices, suggesting that breathiness ‘is often an issue …the teenage girl will have a strong and well-developed lower range and a comparatively weak and breathy upper range’ (Williams, 2013, p.60). Working with the tube, students with ‘breathy’ voices were among those who seemed to benefit most. The simple fact that they found a much more ‘on the body’ support meant that their vocal cords had the required pressure to fully adduct freely. Existing voice breaks in the upper passaggio in younger female students were also tackled using the tube. Singing notes which were unstable and not fully functioning through the ‘break’ were sung with apparent ease through the tube. The combination of relaxation and increased breath support seems to have a particularly positive impact on work in this ‘break’, providing an essential confidence boost for the students.

Another benefit discovered whilst working with the tube was in the realm of resonance across the vocal range. The optimal use of the tube requires the cheeks and mouth area to be relaxed and slack. It was the freedom of these areas promoted by the need for relaxation which helped promote some students to find a much more frontal resonance area adding to the fullness and carrying-power of the tone. Using the idea of recreating the mouth position meant students with tight production in the jaw and mouth were able to experiment with a looser approach. In addition, the tongue position which can be an issue when using words, once tucked with its root at the bottom teeth seemed to be less of an issue when using the phonation tube.

Conclusion

As a voice therapist, Sihvo (2017) articulated her original aims in the development of her approach was, ‘to find some magic wand or something that people would always remember from the first session, and even after a single session understand more about their voice than they did before… They should take responsibility of the progress and the success themselves training every day at home’ (2017 p17). For many participants in this study, the phonation tube was indeed a ‘magic wand’, providing immediate and transformative help with technical issues such as breath control, support, tone and resonance. The most common feedback from participants relates to feelings of ease and freedom experienced as a result of using the device. This freedom and ease, along with an increased awareness of the way in which the breath connects with and supports the voice, represent real benefits for many participants and their understanding and confidence have been enhanced as a result.

 

Based on the introduction and initial use of the device, the study findings suggest that the silicone phonation tube can be a valuable tool for use in singing teaching and learning, allowing students to engage on a practical level with the technical aspects of their singing and facilitating increased independence in the development of safe, effective vocal technique.

 

 

Recommendations for further research

This is a small-scale study of singers in a localised area, already involved in some form of vocal tuition, the majority in traditional one-to-one formal singing lessons with a focus on more classical repertoire and technique. As already stated, the majority of participants were known to the researchers, who as singing teachers participated in the study through the introduction and use of the tube, monitoring progress and providing feedback throughout the process. Some survey participants however were not known to the researchers having been recommended the tube by fellow students or friends. The survey responses suggest that these individuals shared the positive impressions of the device as a singing tool.

The study is also limited in the time frame, focusing primarily on the introduction and initial use of the phonation tube over a three-month period only. Having established that there can be significant benefits involved in the use of the device for singing students of various ages and abilities as represented in this study, it would now be of interest to extend the research, perhaps across more institutions or organisations, or a wider network of teachers, to assess the impact of long-term use of the device as a tool for singing teachers and students. The smallest group represented in the survey sample is professional voice users. It might be useful in future to further explore the use and potential benefits of the device for this professional group, perhaps via a professional body.  There is also potential for a similar study to explore the use of phonation tubes for singers working in other styles and contexts such as pop singers, folk singers and in group tuition, voice workshops or choral warm-up sessions. Also, participants suggested that the device might be useful for players of brass and wind instruments, especially with regard to breath regulation and support. This study concludes that there is clearly potential for further research regarding the effective use of the phonation tube in a range of contexts.

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