Wikipedia
The contraforte (spelled Kontraforte in German) is a proprietary instrument with a similar range to the contrabassoon produced by Benedikt Eppelsheim and Guntram Wolf. It is intended to have improved dynamics and intonation over the distinctive but sometimes reticent sound of the conventional contrabassoon. The contraforte uses a different and wider bore than the contrabassoon to produce a distinct tone.
Wolf and Eppelsheim developed an accurate bore taper and precise keyworks in order to simplify fingerings in spite of the instrument's large size.
In October 2010 Lewis Lipnick, contrabassoonist for the National Symphony Orchestra in Washington DC, played it in a performance of Beethoven's Ninth Symphony. According to Lipnick, the other members of the orchestra, who used to make jokes about the sound of his old contrabassoon, praised the sound of the contraforte. As the soloist of the Helsinki Philharmonic Orchestra in February 2012 Lipnick also performed with the contraforte Kalevi Aho's extensive Contrabassoon Concerto, and as a solo instrument it proved to be superior to the traditional contrabassoon, because of its very wide dynamic range and clear, focused intonation.