Sudan's musicians have gone from persecuted outcasts to high-profile stars. Now, as a referendum on the south's possible independence approaches, there are fears that the same combination of ideology and politics might send them packing again, writes the BBC's James Copnall in Khartoum.
When hardline Islamists took control of Sudan in 1989, they made it clear that a lot of music was not acceptable.
"Women and the arts are the two great casualties of the Islamists," says Sudanese human rights activist Albaqir Alafif Mukhtar.
Songs about that old musical staple - romantic love - were particularly frowned upon.
Some musicians were banned from staging concerts and many musicians, artists and intellectuals fled the country.
At the time the Muslim north, which implemented Sharia law, was engaged in a devastating civil war with the south, where most people follow Christianity and traditional religions.
The Comprehensive Peace Agreement (CPA) signed in 2005, brought an end to what was Africa's longest civil war. It also opened northern Sudan up.
Now cool young Khartoum-ites dance at rap concerts, while traditional singers earn good livings from performing at weddings.
"This is beautiful, it's magic," one young man said, at a recent concert.
"I'm so happy, because I'm free to dance, there's no law and music is an international language," he added, thrusting his shoulders back rhythmically to the beat.
Mr Albaqir says Sudan's new willingness to listen to this international language is due in part to growing economic prosperity.
Then there are the effects of the peace deal - which brought non-Muslim southerners into national government.
"The CPA came with openings and freedoms," he says.
"Also it brought new ideas because when Sudanese people left the country the intellectual vacuum was being filled with Islamist thought."
But the freedom is not absolute.
All large gatherings have to stop at 11pm - sometimes the Morality Police break up events.
But northern Sudanese can now appreciate - and make - music in public in a way that would have been inconceivable a few years ago.
Now you can listen to Western and Arabic pop music on the radio, or go to spoken word poetry events or open mic nights.
But it would be wrong to conclude that Sudan has totally changed.
Imams still regularly condemn music as un-Islamic.
Outside the al-Shahid mosque - a vast structure on the banks of the Blue Nile, draped in decorative lights - young men said they felt their society had gone too far.
"Songs are forbidden under Islam," said one, adding that music encouraged the intermingling of men and women.
"If I was in charge I would ban all concerts," said another.
He might just get his wish.
In January Southern Sudanese will vote on possible independence, as part of the peace deal.
Already in the semi-autonomous south, you can drink a beer in a raucous nightclub, filled with sweaty, scantily-clad dancers near the River Nile.
The concern for many in the north is that if the south does split away, the Islamists who still control Khartoum might re-establish their previously dominant vision of society.
"I do think the government will try to clamp down on society and the rules and regulations," said Mustapha Khogali, a drummer and concert promoter.
"They have even made statements saying they will ban the wearing of shorts and men having long hair and stuff like that."
But Mr Khogali is optimistic that Sudanese society has changed so much that there can be no going back; whatever the results of the referendum.
Fresh from firing out his lyrics in a bedroom rehearsal for his rap group, Rezoulution, 23-year-old Ahmad Mahmoud agrees.
He is uncertain about the future, as speculation that the south will secede continues to spread.
"Some people say that Sudan - the northern part - is going to be like an African Afghanistan. That would take us back to the Stone Age.
"But I'm going to speak my mind about the situation - I'm just going to take it down underground again and just try and rise from there."