Promising Melbourne buskers will need to impress judges in public auditions if they want to secure a prized spot in the Bourke Street Mall, as new permit regulations come into effect.

Twenty musicians will today take part in stringent 10-minute auditions in the hope of receiving a three-year premium busking permit.

While the city has about 2,000 registered buskers, only 140 of the best performers are allowed to play in the mall.

An updated busking rulebook by Melbourne City Council will also detail tougher noise restrictions in response to complaints.

Musicians in the mall will need to keep the volume of their performances below an average of 79 decibels from a three-metre range, down from the previous 82 decibels.

Other performers around the CBD will need to stick to an average of 72 decibels from three metres.

Street poets like Alex Wilkinson will no longer receive busking permits under the new rules. ( ABC News: Nicole Mills )

Acts including portraiture, caricature, balloon twisting and calligraphy will no longer be classified as busking, and these performers will need to obtain street trading permits from late June.

Councillor Rohan Leppert said the new system would prevent large concentrations of street traders in one place.

"We just want to make sure places like Swanston Street have a significant element of music on them," he said.

"We're not trying to stop any of the people going into street trading permits from plying their trade.

"It is about a distribution thing, mainly. It's also about how we regulate street trading, because there's a much more commercial element to it."

For now, the premium busking permits only apply to the Bourke Street Mall, but Cr Leppert said other high-traffic locations could be added in future.

'Amazing' performers expected

Folk-blues singer Aaron Pollock will be auditioning for a premium permit and believes a spot in the Bourke Street Mall will grow his fanbase.

"It gives you a lot of freedom to play whatever you want — it's your spot there for three hours," he said.

"It gives you a lot of leeway to master your show."

Simon Paparo, a current Bourke Street Mall busker and audition judge, said he hoped to see talented female and jazz musicians on show.

"Melbourne is the musical city of Australia, if not the Southern Hemisphere, so I'm expecting some pretty amazing stuff," he said.

Securing a spot in the mall will boost the artists' profile, and Mr Paparo expected they would also earn "a bit more" than other spots around the CBD.

But he said it was difficult to predict how much income an artist could generate from a performance.

"You could earn anywhere from $15 up to maybe $100. It depends on the act and how much of a crowd you're drawing," he said.