Key of T research

When Ari decided to take testosterone to relieve their gender dysphoria, there was little to no research that had been done on what might happen to their singing voice. So they decided to document their voice transition for those who might be facing the same hard decisions.

As a result, Key of T is the first rigorous, empirical research on transgender singing voice transition with external testosterone.

Their findings were published in the study, “Exogenous Testosterone and the Transgender Singing Voice: A 30-month Case Study,” which appeared in the Journal of Singing in March/April 2022 (volume 78, No. 4, pp. 441–455).

If you can’t get the article from your local library and you’d like a copy, please contact us.

Plain Language Summary 

Study Subject and Researchers

I’m Ari Agha, I am both the lead researcher and the “subject” of the study. I am genderqueer and use they/them pronouns. I was 39 years old when I started taking testosterone (or T). While I had sung in choirs my whole life, I had not had many private voice lessons before the study started.

In addition to being transgender, I have a Ph.D. in sociology and lots of experience doing research and studying gender. Laura Hynes (she/her) worked on the study with me. She has a D.M.A. (Doctorate of Musical Arts) and is a professional singer and voice teacher. Together we make a great team to do this research!

I did this study because I was worried about how my singing would be impacted by T and wanted to document my experience so others could learn from it.

Gender Identity Terms

We use the term “transgender” for people whose sex assigned at birth (typically determined by biological characteristics like reproductive organs or chromosomes) does not align in traditional ways with their gen­der identity (sense of themselves as a man, woman, or something else). For example, a person who was assigned female at birth and identifies as a man would be considered transgender. This use of transgender includes people whose gender identity is nonbinary, meaning they do not identify as either, or entirely, a man or a woman. There is disagreement about whether nonbinary identities should be included under the transgender umbrella, but in this article, they are. The term “cisgender” is used for people whose assigned sex and gender identity align in traditional ways. For example, a person assigned female at birth who identifies as a woman would be considered cisgender.

How we collected information about my voice change

We started collecting information about my voice before I started taking testosterone and kept tracking things for 2 ½ years. As part of the study, I took weekly voice lessons with Laura. We collected information on three key factors:

  1. My singing voice – tracked with video recordings of weekly voice lessons
  2. My testosterone and estrogen levels – tracked with blood tests
  3. My feelings about my changing voice – tracked with written journals and video blogs

Anatomy of singing

Before we get into how my voice changed, let’s start with the basics of how voices work.

(Image from

The windpipe (or trachea) is the tube that connects our lungs to our mouth and nose. Vocal folds (also called vocal cords) are mucus membranes that stretch across the top of the windpipe. There’s a picture above. We make sound by bringing our vocal folds together and passing air through them, which makes them vibrate. These vibrating vocal folds are how we speak and sing. Longer and thicker vocal folds create lower pitches, while shorter and thinner folds create higher pitches. Cis men tend to have longer and thicker vocal folds than cis women, which is why their voices tend to be lower.

As kids, there aren’t many differences in how high or low our voices are. When we go through puberty, our vocal folds get longer and thicker, and our voices get lower. We hear more about boys’ voice changes, but girls actually go through a voice change, too,  it’s just that the change tends to be more dramatic for cis boys.

Role of Testosterone

When trans folks who are assigned female take testosterone, our folds get thicker (similar to what happens when cis boys go through puberty) which is why our voices get lower. Sometimes this voice change goes smoothly, but not always. There isn’t very much research on trans voices, but what we have shows that for some people, testosterone can lead to hoarse, weak, and unstable voices. Most of this research focuses on speaking rather than singing.

My singing goals and approach to HRT

My goal was to maintain a healthy singing voice. While I knew my voice would get lower, I wasn’t going for a traditionally “masculine” sounding voice. I loved the sound of the higher part of my range and worried about that changing. Unfortunately, I knew I couldn’t pick and choose how testosterone would impact me. With that in mind, my plan was:

  1. Start on a low dose of testosterone and take a year to get up to a maintenance dose. (NOTE – While this was my plan, it’s not what actually happened, more details below!)
  2. Keep singing throughout my transition, unless it started to hurt.
  3. Keep taking voice lessons throughout my transition. I trusted Laura to help me learn how to use my voice as it was changing, to notice if any voice problems came up, and to help me solve them.

How my voice changed

My voice started changing five months after I started T. The changes leveled off by 14 months. While the physical changes to my voice were done at around 14 months, it took longer for me to learn how to sing and get comfortable singing with a different voice.

Singing range got lower

This keyboard shows my singing range pre-T, the purple and red sections, C3 to C6 and after 2 ½ years with T, the purple and blue sections, G2 to G5. My voice shifted down five ½ steps at the top and at the bottom. While the changes at the top and bottom are important, the purple section is the notes that I could sing both before and after T.

Some people who take T stop being able to sing in the high part of their range altogether, and gradually get those notes back. This didn’t happen for me, though, for me it was just a gradual shift down at the top and bottom of my range.

Tone changed

We focus A LOT on voices getting lower with T, but another really important change was in the tone of my voice. The higher part of my range went from sounding bright and “fluty” to sounding heavier and richer. The tone of the lower part of my range changed, too. It became fuller and sounded more “brassy.” (Below is a table with audio clips of my voice at different points in time.)

Learning to adapt to changes – muscle coordination

We use our muscles differently when singing in the lower part of our range (chest voice), than we do when singing in the higher part of our range (head voice). As my voice got lower, I had to learn this different muscle coordination (also called registration). This process took practice and time and my voice lessons with Laura were helpful in figuring this out.

Examples of my singing voice

Throughout the study, I sang the song “Simple Gifts” as a way to track how my voice was changing. At every point in time, I was able to sing the song in many different keys. Below are clips of me singing in the highest key (D), middle key (A) and lowest key (F) at several different points in the study. You’ll hear that my voice is unstable and cracking as it starts getting lower. You can see that at the end of the study I was still comfortably able to sing in the highest key, but the tone was different. Click ‘X’ to hear the clips.

Clips of my singing voice

 Months with testosterone
      Pre    8.4    9.2    28.4
Highest key (D, range A3 to A4)       X         X
Middle key (A, range: E3 to E4)      X  
Lowest key (F range: C3 to C4)       X       X

How my voice physically felt as it was changing

Beginning at about the same time that my voice started getting lower, both my speaking and singing voice started getting tired much more quickly, after a regular day at work or a regular choral rehearsal. The fatigue did start to get better over time.

I didn’t notice much change in how it felt to sing in the higher part of my range, it still felt easy and resonant. Singing in the lower part of my range felt very different though. I had a lot more power in my lower notes (chest voice). At the same time, though, my voice got very unstable in the area where my voice shifted from chest voice and head voice (A3 to E4 on the keyboard). While I’d sing like I always had, the sounds that came out were not always what I expected. I didn’t have the same control of my voice that I did before. It often felt like my voice would “flip” from chest voice to head voice. It took time and practice to learn how to find a mix between the two and for the transition to be smoother.

How hormones relate to voice changes

While I started on a low dose of T, my bloodwork showed that my testosterone level was within the cis-male reference range from the beginning, 1.5 months after my first dose. This was very unexpected, as the plan was to take 12 months to get up to that level. My T levels stayed within cis-male levels for the entire 2 ½ years of the study. Even though my T levels jumped up faster than we had planned, my voice change was gradual.

Typically, estrogen levels go down when taking T, but that did not happen for me. My bloodwork showed my estrogen level was also higher than the cis-male reference range throughout the study. These higher levels of estrogen may help to explain why my voice change was gradual, even though my T levels increased more quickly than planned. We cannot be sure until there are more studies to see if this pattern holds for others, though.

How I felt, emotionally, when my voice was changing

My emotional experience of voice change was complicated, it was not a simple story of being unhappy before it changed and happy after it changed. In this write-up, I just focus on some of the highlights.

Both before I started T and throughout my transition, I felt a lot of uncertainty. I loved singing and I worried about whether I’d still be able to sing once things started changing. I also worried about whether I would like my voice and feel connected to it, once it started changing. This feeling of uncertainty was with me throughout the process. I had to accept that some amount of uncertainty was normal, even if it was uncomfortable.

I was incredibly excited when my voice did start to change! My voice was one of the first physical changes, so it was a big relief to notice the testosterone having an impact. Right after the excitement, though, the worries came back. Here’s a quote about how I was feeling:

It’s exciting that things are changing, and that’s great, and at the same time, it’s like, “Oh my god, things are changing!” I want them to change, and at the same time, it’s frightening that they’re changing.

As I mentioned above, I really enjoyed the high part of my singing voice and was worried about that part of my voice changing. I was relieved that, for the most part, I continued to be able to sing in that part of my range. Here’s a quote about that:

It felt really good, in my body, to produce those sounds. . . With all of the ways my voice has been changing, it was reassuring that I’m still singing alto . . . I felt this connection with my voice and with what my voice has always been.

As I said already, as my voice was changing, it got tired more quickly than it did before. It was also unstable with a lot of cracks and breaks. This part was very frustrating. Here’s one example of what that was like:

I try never to push my voice beyond what is comfortable. This is much easier said than done, though, because I love to sing. I want to sing. In (choir) rehearsal, I’m surrounded by singing voices, and it’s frustrating to have to stop for a while or hold back.

What we do, and do not, know from this study

Here’s a summary of my singing voice changes with testosterone:

  • My range started getting lower five months after I started to take testosterone and continued getting lower until about 14 months after I started, when it leveled out.
  • My range shifted down five ½ steps at the top and the bottom.
  • In addition to a change in range, the tone of my voice changed with my higher notes getting richer and my lower notes getting fuller and more brassy.
  • It took time for me to adjust and learn some new technique to make it easier for me to sing as my vocal folds got thicker.
  • As my voice was changing, it got tired more quickly and it was hoarse, weak, and unstable. This got better with practice and over time.
  • Emotionally, it was hard not knowing what my voice change would be like. When changes did happen I was both excited and happy and also unsure, because part of me was sad about missing the way my voice sounded before.

This is ONLY my experience, though. Knowing what happened to me is useful, but it doesn’t mean the same thing will happen to other trans folks who take testosterone. My experience is just one example.

A few suggestions

While we still have a lot more to learn about how external testosterone impacts singing, here are some suggestions for folks thinking about taking testosterone or who have already started:

  1. Keep singing throughout the process, as long as nothing hurts. It can be disappointing when your voice is feeling shaky, but continuing to exercise it can help you get used to the changes. If anything hurts, get connected with a voice teacher for help.
  2. To help with the tiredness, drink plenty of water and take speaking/singing breaks when you are able. Consider adding a warm-down after you’re done singing. If you sing with a choir, consider doing some extra warm-up before rehearsal.
  3. Tell the doctor who is prescribing your testosterone that singing is important to you, so they can keep that in mind.
  4. Get connected with a voice teacher, especially one who has experience teaching trans/non-binary singers. This is a list of singing teachers who want to work with trans singers. Some choral directors can also be helpful in learning to adjust as your voice changes.

Blog posts about Ari’s experience

Ari’s blogs at . These three posts are especially relevant to their voice transition:

To T or Not To T? (September 11, 2016) – This essay was written before Ari began taking testosterone, in it they reflect on their gender, their voice, what singing means to them, and the complex decision in front of them.

A Farewell to Altos (and Sopranos) (May 16, 2017)- This essay was written eight months after Ari started taking testosterone. Their voice had begun to change and here they explore some of their feelings of loss and grief associated with that change.

Singing in the Cracks (April 21, 2018) – This essay gives a detailed description of how Ari’s voice has changed in the first 15 months of testosterone therapy and reflects on the emotional ups and downs of singing through these changes. It draws parallels between having both a voice and a gender identity that do not fit into existing categories.

**Bonus Resource** Making Your Chorus Welcoming for Transgender Singers – An article Ari wrote for Chorus America’s magazine, “The Voice”.

Other resources

These are some additional sources that provide useful information about external testosterone and transgender sing, but not all of them are grounded in a sound understanding of gender. For better information about transgender and non-binary experiences and terms, we recommend readers consult resources focused specifically on these topics, like those listed in the Transgender and gender-expansive identities section below.

Adler, Richard K., Sandy Hirsch, and Michelle Mordaunt. (2012) Voice and Communication Therapy for the Transgender/Transsexual Client: A Comprehensive Clinical Guide. San Diego: Plural Publishing.

Constansis, Alexandros N. (2008) The Changing Female-To-Male (FTM) Voice. Radical Musicology, 3.

Constansis, Alexandros N. (2013) The Female-to-Male (FTM) Singing Voice and its Interaction with Queer Theory: Roles and Interdependence. Transposition, 3, p.1 – 22.

Damrose, Edward J. (2009) Quantifying the impact of androgen therapy on the female larynx. Auris Nasus Larynx, 36, p.110 – 112.  

Davies, Shelagh. (2016, April 14). Training the Transgender Singer: Finding the Voice Inside. What’s New, National Association of Teachers of Singing website.

Davies, Shelagh, Papp, Viktória G. & Antoni, Christella. (2015) Voice and Communication Change for Gender Nonconforming Individuals: Giving Voice to the Person Inside. International Journal of Transgenderism, 16(3), p.117-159.

Graham, Felix (2022): To t or not to t: The transmasculine singing voice on hormone replacement therapy, Voice and Speech Review, DOI: 10.1080/23268263.2022.2038349.  

Hearns, Liz Jackson and Kremer, Brian (2018) The Singing Teacher’s Guide to Transgender Voices. Plural Publishing. ISBN13: 978-1-63550-093-6.

King, A., Ashby, J. & Nelson, Christella (2001) Effects of Testosterone Replacement on a Male Professional Singer. Journal of Voice, 15(4), p.553-557.

Manternach, Brian, Michael Chipman, Ruth Rainero, and Caitlin Stave. (2017) The Independent Teacher: Teaching Transgender Singers. Part 1: The Voice Teachers’ Perspectives. Journal of Singing 74(1), p.83-88.

Manternach, Brian. (2017) The Independent Teacher: Teaching Transgender Singers. Part 2: The Singers’ Perspectives. Journal of Singing 74(2), p.209-214.  

Saurland, William (2002). Queering Vocal Pedagogy: A Handbook for Teaching Trans and Genderqueer Singers and Fostering Gender-Affirming Spaces. Rowman and Littlefield.

Sims, Loraine. (2017) Teaching Lucas: A Transgender Student’s Vocal Journey from Soprano to Tenor. Journal of Singing 73(4), p.367 – 375.

Transgender and gender-expansive identities

These websites are a good place to get started learning about transgender and gender-expansive identities.

About Transgender People Resource Hub – National Centre for Transgender Equality    

Nonbinary 101 – Seattle Nonbinary Collective    

Transgender 101: A Guide to Gender and Identity to Help You Keep Up with the ConversationEveryday Feminism, by Sam Dylan Finch (August 10, 2016) 

Transgender FAQGLAAD