(Image Credit: ABC News)

A symphony of negative comments left on review sites about a Chicago violin store were likely all left by one person, and now the store's owner wants to unmask the anonymous critic and also make him or her pay.

The person used a handful of pseudonyms, including TRUTHETELLER1790, TRUTH TELLER and TRUTH T to review Guadagnini Violin. All negative reviews using these various nicknames were traced back to the same IP address.

One review on Yelp asked if anyone wanted "to buy a gold mounted tortoise shell bow for $4,500 that's actually worth $800 and made of gold-colored metal and faux plastic shell," the Associated Press reported. If so, the the review said, "then please go to this shop!"  That review and other negative posts have since been deleted.

James Branit, a lawyer for the shop's owner Cunyee Lu, said the reviews crossed the line into falsehoods,  and therefore are not protected speech.

"[The reviews] contain false statements of fact that slandered the shop and Mr. Lu by saying he engaged in improper business actions," Branit told ABCNews.com. "I believe there is a possibility it is a competitor [who posted the reviews]."

But before there can be dueling violins in a Cook County, Illinois courtroom, Branit still has to unmask the anonymous critic.

Under an Illinois law, Branit was able to obtain the IP address from Yelp through the courts, he said. From there he traced it to the cable provider RCN.

"Here's the problem," Branit said,  "Sometimes the IP addresses are IP routers, such as if a person connected in a coffee shop. I don't know yet whether we'll be able to identify them."

Branit said his client is asking for damages "in excess of $50,000?.

"Reviews can be a good thing if they are honest and done by actual individuals who identify themselves," he said.