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. The L-5 guitar owned by Maybelle Carter, which was made after he left Gibson, sold for $575,000.