Jiji Press/AFP/File
Mamoru Samuragochi said his impairment had improved in recent times, but when he first paid part-time music school teacher Takashi Niigaki to pen works in his name, he had been unable to hear.
"I feel deeply ashamed of myself for living a false life," Samuragochi said in a hand-written statement.
"I also apologize to Mr. Niigaki, whose life went wrong because of complying with my demands for 18 years.
"In recent years I have started to be able to hear a little bit more than before... since about three years ago I can hear words if people speak clearly and slowly into my ears.
"It is true that I received a certificate proving I had a hearing disorder and that I couldn't hear anything up until three years ago," he said.
The scandal broke last week when Samuragochi, who is credited with being behind an anthemic tribute to the tenacity of Japan's tsunami survivors, admitted he had been paying someone else to write his music for nearly two decades.
Deafness 'an act'
A day later, Niigaki came forward to hold a lengthy press conference in which he revealed he had earned just seven million yen ($70,000) for writing more than 20 pieces and claimed Samuragochi's hearing disability was an act.
"I've never felt he was deaf ever since we met," Niigaki said last week. "We carry on normal conversations. I don't think he is (handicapped)."
His lawyers said Wednesday they had also been duped by his pretense.
"We had explained to journalists that he was mostly likely deaf, because he had an official certificate showing he was hearing-impaired," they said in a statement.
"In addition to that, we had taken on board what a sign language interpreter had said and what our own impressions were. As a result we were wrong."
Japan's often sentimental media had previously lapped up Samuragochi's story, feasting on the narrative of a tortured genius robbed of the ability to hear the beautiful music he made.
Samuragochi's star burned all the brighter after a documentary entitled "Melody of the Soul", was shown on NHK last year.
Cameras followed Samuragochi, whose long, flowing hair and permanent sunglasses made him look the part, as he toured the tsunami-battered Tohoku region to meet survivors and those who lost relatives in the 2011 catastrophe.
The film showed Samuragochi playing with a small girl whose mother was killed in the disaster and apparently composing a requiem for her.
"I'm determined to quit telling lie after lie," his Wednesday statement said.
"I swear by heaven and earth that what I write here today is the truth."
And, in a move that will have set pulses racing in newsrooms across Japan, he pledged to appear in public to offer contrition in person.
"I feel I am finally ready, so I promise I will make my direct apology publicly sometime soon."
The public apology is an important ritual in Japan for shamed company executives or pop stars who have fallen from grace, attracting a room full of photographers eager for a shot of the requisite deep bow.
Meanwhile, Japanese Winter Olympics medal hopeful, figure skater Daisuke Takahashi, said this week the revelation that "Sonatina for Violin" had not been composed by Samuragochi would have no bearing on his use of it during his short programme on Thursday in Sochi.
"I wasn't sure whether I could still use this music or not," he told reporters. "I didn't know the background when I chose it; I just liked the music.
"It wasn't something I was aware of. I hope this problem will be solved, but I am still happy to be able to use this music for skating."