For a youthful new member of the Barbershop Harmony Society, an honest mistake leads to a gesture of careful teaching and a lesson in kindness, discretion, and respect.

It was 1 am. I was twelve.

I was at a weekend gathering of a few thousand men who stood in small groups, much closer to each other than many men would feel comfortable, making music with their voices. It was my first full experience of the fellowship and family atmosphere of the four-part a cappella style called barbershop harmony.

Most of the 35,000-plus members of the all-male Barbershop Harmony Society in the us—the largest singing organization in the world—sing for pure, personal enjoyment, but they can’t do any of it alone.

Ensemble singing is all about collaboration: each person plays an important role balancing and tuning, relative to the key and each chord. We form a bond when singing together, becoming one voice, one instrument, but that voice falls apart when even one person doesn’t do what he is supposed to. Understanding your place within the group, the role you play from first breath to last chord, as well as your responsibility to the other singers in your group and to the audience, is just as important as singing in tune.

I was up late that night singing tags, an aspect of the hobby to which only members are typically privy.

To fully grasp how thrilling tag-singing can feel, you need to experience it and be a participant. A tag is, to paraphrase the society’s oft-quoted historian David Wright, a short passage consisting of an arrangement’s ending, learned and sung in sessions of informal chord-ringing. Instead of requiring the foursome to learn an entire song, the tag allows the singers to quickly blend their voices in a few seconds of what he calls “blissful harmony.”

I’d been a member for a few months, singing with the local chorus in preparation for competition. We sang tags outside the rehearsal hall after each Thursday night meeting, so the process was familiar. As with any collaborative endeavor, tag-singing is replete with unspoken, unwritten rules we must understand in order to fit in, to be part of the group—rules that often take time to learn and understand. Many types of vocal harmony thrive throughout many genres of music; barbershop has especially strict rules and traditions.

Standing with me that night were four men who, including the director of my chorus, Ed Knight, were each old enough to be my grandfather. Ed must have been in his late fifties back then, graying and balding, and at well over six feet he towered over everyone, especially a twelve-year-old who hadn’t hit his growth spurt, but that didn’t bother me. I had been made to feel an equal in my few months as a member, and though I had only just met the other men in that room a few hours before, I didn’t feel out of place. I was deeply enjoying every minute, realizing that I had discovered something I wanted to do for the rest of my life.

My mistake was simple enough. As the other men were singing a tag Ed had just taught them, I too had learned the tenor part and was standing next to them singing along very quietly. Most of my experience as a barbershop singer had been with a chorus of a few dozen men, so singing along seemed perfectly normal to me.

I was, however, joyfully unaware that I was committing tag singing’s cardinal sin: adding my voice to the four parts already in play. By singing along, I was interrupting the delicate interplay of tuning, vowels, balance, and placement that contribute to the perfect alignment of each voice’s harmonics—the almost magical effect of physics that makes the sum of four voices sound greater than its parts.

The next week a postcard arrived from my chorus director thanking me for my participation in the weekend’s festivities. Ed explained what a joy it was for the chorus to have my younger brother and me on stage with them, that he hoped I enjoyed myself, and that he was proud of us. He then added, almost as a postscript, that singing along with a foursome’s tag is not appropriate and that he knew I’d not do it again.

That postcard also included five simple words I’ll never forget:

“Don’t be a fifth wheel.”

Teaching is about tone and timing as much as it is about the subject itself. Ed could have scolded, discouraged, or intimidated me. But though direct in his speech, he was kind, and this allowed me to feel comfortable enough to approach him at the next rehearsal to ask for more detail and to apologize for my misstep. By allowing me to enjoy the moment, he protected my positive association with the act of singing. My lesson arrived later: privately and when the time was right.

Teaching—or collaborating, as I have learned in my design career—with kindness and respect allows the other person to learn or act without fear. We can positively affect the behavior of others by building them up rather than tearing them down. We should be looking for more ways to work together and make each other stronger, even when pointing out a fault or mistake.

I still have this postcard tucked safely away in a box of my life’s most treasured memorabilia. Its tone still teaches me twenty-one years later as I interact with other people in my role of collaborator, teacher, designer, singer, friend, and perhaps one day, father.

Dan rubin

Dan Rubin is a designer, photographer, and barbershop harmony aficionado based in London. Founder and creative director of webgraph, Dan speaks at conferences around the world, writes about myriad topics, and works with good-looking clients including The Guardian, Red Bull, MailChimp, Google, Yahoo!, Microsoft, Geffen/Universal, IDEO, and Nokia.

Read Next: Dan Rubin’s Article

Portrait by Ping Zhu