(piano playing) - You can hear once you go back up in here, it's nice and bright again, but there is a a darkening of the tone through that region that we need to address.

- [Narrator] It is two hours before curtain at Pittsburgh's Heinz Hall and Peter Stumpf is making the piano concert ready.

Peter is a piano technician and on this night he is tuning the concert grand piano, recently purchased by the Pittsburgh Symphony Orchestra.

- It's an honor.

I feel very grateful.

Every time I come out on this stage, I tingle a little bit.

You look out and you see all the lights and it's like stars in the sky.

- [Narrator] The work is delicate, almost surgical in its precision and Peter performs his craft in much the same way it's been done for generations.

- [Interviewer] Do you have perfect pitch?

- I do not, but my tuning fork does.

- [Narrator] For the next hour, Peter will hone the instrument, coaxing music from the metal and wood and felt and from time.

(relaxing piano music) - [Peter] And when we hear concerto 5 or 10 years from now, we need to keep in mind that it was the brushstrokes of dozens of artists before them that helped to build that tone.

(relaxing piano music) Someone can use an instrument that I've prepared to that level.

It's terrific.

(orchestra music) It moves me like nothing else.

It's like painting on time.

(orchestra music) This orchestra paints on time so beautifully.

- [Narrator] The pianist is Martin Helmchen, the visiting artist for this performance of Schumann's Concerto in A Minor.

It was one of the first public performances on the new piano.

Peter has tuned pianos for the best musicians in the world, but he spent much more time tuning the pianos of less renowned players in private homes all over Western Pennsylvania, as many as 40,000 pianos.

This time of year is always busiest.

- Typically, I do the first tuning using an electronic tuning device.

Give my ears a break.

It's much like chipping onto the green and then the second tuning, I come back orally and do a good tuning on it.

So many people are putting so much energy into decorating their homes and planning programs and things that I get to participate in.

It's fun going from place to place, from churches into schools.

- [Narrator] A few miles and a few days later, Peter was at First Baptist Church in Oakland to tune the piano for a holiday concert by the Pitt Men's Glee Club and Women's Choral Ensemble.

(piano playing) - [Peter] In this case, it's a big, beautiful open space.

- [Interviewer] What can cause a piano to go out of tune besides time?

- Oh, a lot of things.

Temperature, relative humidity changes, you know, a good bump, heavy playing.

New pianos are gonna go out of tune just because the strings are still stretching.

Well, the piano's gotta be spot on.

There's no way it can be anything else.

But that's gonna make it a great event.

- [Conductor] We go from this alpha.

(choral group singing) - You want to hear the piano, but it's very easy to, in this kind of a very vibrant space for it to get too loud.

So having a good instrument that you can actually regulate all those different dynamic song is important.

(choral group singing to piano) - It is a beautiful moment when the things are right.

When the piano is right, and the literature is right, and the mood is right, and it's all coming together.

It's a beautiful convergence.

- [Narrator] His work is not just tuning.

He also makes mechanical adjustments as with this piano that will be someone's Christmas gift.

It was mechanical work like this that led Peter to prepare a piano that was used in the film "It's a Beautiful Day in the Neighborhood" in which Tom Hanks portrayed Fred Rogers.

- They wanted to film without the pianos making any sound whatsoever.

So whenever Tom Hanks sat down at the instrument and played, they wanted to hear nothing.

But they wanted the piano to function fully and then dub the music over later.

So I had to put a 90 gram weight on the back of each key on the back check to weigh it down so that it would simulate the proper touch weight on the front.

I have a lot of gray hair and when you've been around for a while, opportunities tend to present themselves.

- [Narrator] And maybe Peter's favorite work is the work that takes him into somebody's home.

- And if there's a little four year old starting lessons or if there's a 60 year old woman that loves to play Christmas Carol, they're all wonderful.

Everybody has a different thing that connects 'em to the instrument.

(orchestra music) - [Narrator] For every concerto performed by virtuoso hands on a grand piano in a grand concert hall, (piano music) there are a thousand quiet little songs played by humble hands on an old upright in a living room somewhere.

(piano music) And they sound even sweeter because the piano man touched it.

(piano music) - [Peter] Absolutely lovely.

This is why I do this work.

(piano music)