Stacy Tolman was based in Boston when he painted this, and he liked to depict artists and musicians at work. The setting is most likely the studio he shared with another artist.
Artists in the 1880s often decorated their studios with beautiful objects that they had collected on travels, to show that they were very cultured, and other interesting things that they might want to use as props in their art. For example, there's an Asian parasol on the wall in this scene.
Westerners (including Americans) were very interested in Japanese art, in particular, during this time. You will see other Asian-inspired furniture and objects near this painting.
Did the artist actually know how to play the violin?
I wonder if Stacy Tolman actually could play the violin! The person he depicts playing the cello is actually Bicknell, an artist who was a friend of Tolman and also a talented cellist, so if Tolman could not actually play the violin, he is putting himself in good company!