Beethoven's Symphony No. 10 in E flat major is a hypothetical work, assembled from fragmentary sketches left by Beethoven, by Barry Cooper in 1990.

Beethoven never completed a Symphony No. 10; indeed, he may never have started one. After completing the Ninth Symphony, he devoted his energies largely to composing string quartets, although there are contemporary references to some work on an orchestral piece; allegedly he played some of his ideas for this piece for his friend Karl Holz. Calling Barry Cooper's work the "Symphony No. 10" has proven to be rather controversial, since it cannot be proven that all the sketches assembled were even intended to be part of the same piece. Cooper claimed that he found over fifty separate fragments which he wove together to form the symphony.

Though this work remains controversial, there is a consensus that Beethoven did intend to complete another symphony. There are numerous references to it in his correspondence (originally, he had planned the Ninth Symphony to be entirely instrumental, the Ode to Joy to be a separate cantata, and the Tenth Symphony to conclude with a different vocal work.) Most scholars consider Cooper's work to be a useful work of scholarship, but do not consider the Tenth Symphony to be an authentic addition to Beethoven's canon.

"Beethoven's 10th Symphony" is also an appellation given to the Symphony No. 1 of Johannes Brahms, due to its often-perceived similarity to the Beethoven Ninth, including a thematic similarity between the principal subject of the final movement in both works. The nickname was originally given by Hans von Bülow, and it is still used today.

Cooper's realization of the Beethoven Tenth lends some credence to calling Brahms's First "Beethoven's Tenth". For example, notice the very Brahmsian use of the clarinet in the Cooper realization (at about 10:30 in the Wyn Morris recording).

External links

• Article on methods behind construction of 10th symphony
• Amazon.com page