Grossman Music Co. (or Corp.) is a musical instrument distributor based in Cleveland Ohio . It was founded by brothers Henry and Julius as Grossman Brothers in 1922 to distribute "only Stringed and Band Instruments" and as still in business today. It appears that at some point in the past Grossman took over Grover another Cleveland manufacturer famous for their tuning pegs, banjo tailpieces and other musical accessories, (it should be noted that Grover has only ever been used to brand the machine heads and has never been used to brand actual instruments though some people have mistakenly attributed instruments to Grover because of the then name on the parts), and this seems to be a major part of today's business, along with some band instrument and drum distribution plus a budget Chinese import Soprano they brand Trophy Music. 

Like most distributors they never actually made the Ukuleles or Banjoleles under their own name but they did register and brand a lot of the instruments they distributed. Brands that they registered over the years include KlearTone (reg. 1923 and nothing to do with Kleertone strings), Champion (1932), Capitol (1933), Duplex (1937), Masterfonic (1937), Trophy (1945), Dixie (1948) and Crestline (1957). Of these brands, I have seen KlearTone Ukuleles and Banjoleles, (as well a Guitars and Mandolins), from the 1920's and 30's plus Champion, Capitol and Crestline Ukuleles, but all dating from the 50' and 60' and made in Japan. Grossman did also have a manufacturing division called Trophy Products which primarily made plastic "novelty" musical instruments but also made the all aluminium Dixie Banjo. In 1950 Josephus Thompson, (an associate of Henry Grossman who ran Trophy with Henry's nephew Ben Straus), applied for a patent for an all metal "Banjo-Ukulele" (I believe it was granted in 1954). The parts for this were made in aluminium foundries and plated using outside sources with the final assembly in Covington and later Cleveland. (How the later Werco Banjolele ended up using a lot of the same parts as the Dixie is something I still don't know; anyone?) Then there are some brands I have seen them associated with but not the actual registration, brands like Buckeye and Red Dragon and Little Pal. They also distributed instruments endorsed by celebrities, including Kenny Roberts the Cincinnati Cowboy and his Little Pal line. They also owned the famous drum maker Rogers for a while too.