Baritone Not Tenor

I think I'll ask Mac
To sing a duet with me
We can talk about the song
It must have perfect harmony

Mac can sing the melody
With his voice in Tenor true
I will sing the harmony
In my pure Baritone for you

I used to think I was Alto
But soon found out this wasn't right
Many years later I was told
You're a Baritone whose voice is bright

So I enjoyed my singing
In the Church choir
Standing with the other men
Didn't exactly make me inspire

But never the less I did sing
For many years and so
Cantata's came around each year
And my Baritone voice did flow