ISLAMABAD - Moments before dawn, Noor ul Islam ascends the steps of one of the world's biggest mosques, enters its cavernous hall and says a private prayer before a faintly buzzing microphone.
Then, the 32-year-old gulps down a deep breath and makes the morning's call to worship -- a forceful yet lilting chant amplified across Islamabad, Pakistan's capital, marking the start of daylight fasting during Ramadan.
"The voice is a gift from God," Islam told AFP at Faisal Mosque, a towering marble monument to the nation's devotion to faith.
"If your intentions are genuine, your voice will have the power to touch people's hearts," he said.
All across the Muslim world, men like Islam, known as muezzins, broadcast the "adhan" call to prayer, five times a day.
In the month of Ramadan, where prayers mark the start and finish of 14 hours of fasting in Pakistan, the faithful are particularly attuned.
The script and rhythm are the same everywhere.
Intoned in Arabic over minaret loudspeakers, it reminds Muslims: "God is the greatest" and they should "hasten to prayers".
But there is a quiet hierarchy among muezzins.
A particularly melodic caller can increase the standing of a mosque. House hunters might judge the neighbourhood adhan before making an offer. And at prestigious mosques, the job is highly coveted.
The three muezzin roles at Faisal Mosque -- a national emblem opened in 1986 with a fabled capacity of 300,000 worshippers -- are among the most prized outside the holy sites of Mecca and Medina.
Some of Islam's fellow muezzins coddle their vocal cords like rock stars and theatre performers, drinking honey-laced beverages, and avoiding cold breezes and oil-drenched Pakistani cuisine.
Devotees travel for miles to hear the call at Faisal Mosque, peer through the windows to watch Islam at work and ask for selfies afterwards.
Back home in the town of Swabi, he is considered a local hero.
Now Islam aspires to secure a further promotion to muezzin at the Grand Mosque in the holy city of Mecca.
"I can't explain these feelings," he said. "Every Muslim should try to make this bond between him and God."
"There is peace in this."