Lloyd Allayre Loar (1886–1943) was an American musician, instrument designer and sound engineer. He is best known for his design work with the Gibson Mandolin-Guitar Mfg. Co. Ltd. in the early 20th century, including the F-5 model mandolin and L-5 guitar. In his later years he worked on electric amplification of stringed instruments, and demonstrated them around the country. One example, played in public in 1938 was an electric viola that used electric coils beneath the bridge, with no back, able to "drown out the loudest trumpet." In 1898 Orville Gibson had patented a new kind of mandolin that followed violin design, with its curved top and bottom carved into shape, rather than pressed. The sides too were carved out of a single block of wood, rather than being made of bent wood strips. The instruments were already unique before Lloyd Loar came to work for Gibson. However, it is the Loar-designed instruments that became especially desirable. First made famous by Bill Monroe, Loar's signed mandolins today can cost as much as 200,000 dollars. The L-5 guitar owned by Maybelle Carter, which was made after he left Gibson, sold for 575,000 dollars. Among the changes that Loar introduced was the f-hole instead of a round or oval sound-hole, another violin-family feature imported to the mandolin. He also "tuned" the tops of the instrument and the sound chamber (by removing bits of wood from sound bars and from the edges of the sound holes) so that the instrument's sound chamber was resonant to a particular note. Another change that Loar introduced to the Gibson line was a tone-producer, a circle of wood inside the instrument on the underside of the sound board that produced "overtones." His idea was to have a more complete set of these overtones with the carved top instruments. The result was an instrument that, like Stradivarius’ violins, has presented challenges to duplicate. Luthier-researchers such as Roger Siminoff have worked to understand the fine details. Gibsons' and Loar's mandolins were instrumental in displacing the round-backed instrument from the American market and influenced mandolins worldwide. He also developed keyboard-stringed instruments. According to Roger Siminoff, he developed unique mechanisms to create sound. One plucked strings, the other struck metal reeds. Loar was also a well-regarded musician on mandolin, viola, and musical saw. He traveled the United States and Europe in several musical groups. In one group, he performed with his