Random Riddle: 11-19-2014

I’m full of keys whenever I’m made
I came about wooden when the Renaissance played

Hundreds of years later, I was divided
And two new keys to me were provided

Then in 1760, and that’s forty years later
Three keys were added by Florio, Gedney, and Potter

Around the 80’s of the century mentioned
I was used by Mozart and Haydn

Over the years, new keys were gained
In the 1830’s, Beethoven used me to entertain

Near the end of the 1800’s, or the 19th century
I was used by Brahms, Strauss, and Tchaikovsky

Now, modern renditions are made of me
Without my holes, I wouldn’t be

What am I?
 

Riddle