[Could you mention the source please? In the text of "Вишневый сад" on the link I gave above, there is no this word. It is said there, "Слышно, как в передней играет
еврейский оркестр, тот самый, о котором упоминается во втором акте."
Rafael, could you tell us about your source, too? Is it a book or a source on the Internet?
P.S. Google gave me only ONE page with the word combination "тройский оркестр", and that was
http://ilibrary.ru/text/472/p.3/index.html
Obviously it is a OCR mistake, otherwise it would be much more results.