Stroh violin
The Stroh violin or Stroviol is a type of stringed musical instrument that is mechanically amplified by a metal resonator and horn attached to its body.[1] The name Stroviol refers to a violin, but other instruments have been modified with the amplification device, including the viola, cello, double bass, ukulele, mandolin, and guitar. Johannes Matthias Augustus Stroh, an electrical engineer from Frankfurt, invented the instrument in London in 1899.
Invention[edit]
On 4 May 1899, Stroh applied for a UK patent, GB9418 titled Improvements in Violins and other Stringed Instruments which was accepted on 24 March 1900. This described the use of a flat metal (other materials are also mentioned) diaphragm in the voice-box (reproducer) of a violin to mechanically amplify the sound.[3] On 16 February 1901 he applied for a second UK patent, GB3393 titled Improvements in the Diaphragms of Phonographs, Musical Instruments, and analogous Sound-producing, Recording and Transmitting Contrivances which was accepted on 14 December 1901. This effectively extended the first concept to now use a conical resonator with corrugations at its edge, allowing a more 'rigid' diaphragm. His failure to register his inventions in the USA allowed John Dopyera and Geo Beauchamp to subsequently obtain US patents for the tricone and single cone designs used in National brand instruments.
Romanian horn-violin and its bow
The diaphragm of an old-fashioned gramophone serves as the receiver of the vibrations that are transformed into sound waves in the horn
The Romanian horn-violin is similar to the Stroh violin. It was built through the 20th century. It has the same length as the Stroh violin, but its horn is narrower and yields a more directional sound. The structure of the instrument is based on the tungsten element of a gramophone. Amateurs or small workshops could easily build it and, perhaps for that reason, many variants exist in Eastern Europe.
The vibrations of the strings and bridge are transmitted by a thin rod to the membrane of the gramophone-element. The membrane transforms these vibrations into sound waves, which are amplified by the horn or beaker.
The horn-violin is harder to play than a normal violin because the reaction of the bow on the strings is less flexible, and the instrument's weight is less evenly distributed. This causes an imbalance on the shoulder.
The instrument is still used in Romanian folk-music for playing horas and doinas, and mixes well with the characteristic sound of the pan-flute. It is generally used sparsely due to its tone. Instruments like the Stroh violin and other types of horn-violin remain a curiosity; they are quite rare in the orchestra.
The horn-violin is especially used in folk music of the Bihor region of Romania. Famous practitioners of this music style include fiddler Gheorghe Rada, singers Florica Bradu, Florica Ungur, Florica Duma, Leontin Ciucur, Cornel Borza, Vasile Iova, Maria Haiduc, Viorica Flintașu, and renowned folk ensembles Crișana or Rapsozii Zarandului.