Back in the mid 70s, KJ Leisuresound used to sell their 'own brand' speakers, most notably the 'KJ Sonata', a simple little two way bookshelf selling for around £30pr.
They also employed Robin Marshal as a sort of all round technical wizard. They decided to make some rather more upmarket speakers that he designed and sold them under the Audiomaster brand name. As noted above, they also had a license to built LS3/5As and tried to market Audiomaster separately from the whole KJ empire, it was not very successfull.
Marshall left to become pretty much a designer for hire, some of his designs for monitor audio have been discussed in another thread, and Audiomaster withered and died.
The Stereophile link above will give you more detail.