'I told my wife I thought I could be a great composer. Understandably, she thought I was deluded. I couldn't even read music, let alone write it'

I grew up being told I had all the musicality of a brick. I couldn't read or write a single note; music just didn't feature in my early years. Instead, my life followed a traditional path – I married my wife, Jo, at 21 and our daughter Emma soon came along. We were expecting another baby when things took an awful turn.

During labour, the contractions stopped and the doctor couldn't find the baby's heartbeat. He performed an emergency forceps delivery, but there were terrible complications. Our baby died and Jo suffered serious injuries during the birth. Her life was in the balance and she needed major surgery.

I was devastated beyond words. I felt like giving up, but I had to hold it together for both Jo and two-year-old Emma. I felt utterly crushed and empty when I went to bed that night.

But as I fell asleep, I had a wonderfully comforting dream. All I could hear was music. When I woke up, I couldn't stop replaying it in my mind. It wasn't just a simple melody, but a symphony. And somehow I could identify each instrument and every note.

It felt very odd suddenly to have this awareness, and I wanted to see if I could make something of it. But I was working as a cook in a rural pub in Leicestershire and couldn't just drop everything.

Jo and I never discussed the death of Ben, our baby son – it was just too painful – and we focused instead on bringing up Emma and our new daughter, Kate, whom we adopted shortly after Jo had recovered. Without an outlet to process what had happened, the music in my dream was a way of grieving for Ben, and the longer I put off recreating it, the more frustrated I became.

I felt desperately trapped and unhappy, and started to drop hints to Jo. "I think I could be a great composer," I'd say. Understandably, she thought I was deluded. I don't blame her – I couldn't even read music, let alone write it.

I loved my wife and children, but I really wanted to see if I could be a composer. Jo reluctantly agreed to let me go to London and she gave me six months; I would keep in contact regularly.

I had nowhere to stay and ended up living in a squat, earning a few pounds here and there. One day I sat on a bench outside BBC Television Centre and a man stopped to chat. He was a musician called Anthony Wade and after I told him my story he listened to the very rough recording I'd made using a guitar I'd bought for 50p. He was amazed by it and told me that it could be magnificent if it was orchestrated, but that would take hundreds of thousands of pounds.

This was a blow, made doubly worse when I discovered that Jo had met someone else. I was devastated, but it made me even more determined to achieve my goal. I set myself the task of earning enough money to hear my symphony played by an orchestra. It took 15 years of working 20 hours a day as a business consultant, but finally I was able to search out Anthony Wade again, who was dumbstruck to discover the homeless person he'd chatted to had raised so much money.

He helped me put together a demo tape and put me in touch with the conductor Allan Wilson, who was initially deeply sceptical. After he listened to the demo, he told me that I had done the equivalent of brain surgery without going to medical school and that it could be a masterpiece.

Allan booked the Philharmonia Orchestra and finally, more than two decades after my son's death, I would get to hear the music played as I'd dreamed it. As the musicians arrived at Abbey Road Studios, my heart was pounding so much I could barely stand it. I had sacrificed so much to arrive at this moment. Then the baton was raised and I heard my Angeli Symphony for the first time. I was incredibly moved. It was like seeing the birth of a child, as the notes were released from my dream at last.

The orchestra gave me a standing ovation after it was over, but I was so overwhelmed that it was hard to appreciate it. Fifteen years on, I have written another four symphonies: somehow musical ability has been released in me. I will never forget that first one, though – I still can't quite believe I wrote it.

• As told to Emily Cunningham

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