MediaWorks says it has boosted twenty-fold the power of its smallest station - George FM - increasing competition in Auckland's congested commercial radio market.

The new transmitter for FM 96.8 off the Sky Tower boosts the station's output from 25dBW to 39dBW.

George FM station manager Emily Turnbull said it had changed the dance music station from "an urban station" limited to the city's inner west to a competitor in the commercial market for greater Auckland.

MediaWorks - owned by Australian private equity company Ironbridge Capital - bought George FM in February this year, a year after it obtained independent station Mai FM.

Both George FM and Mai FM operate on radio frequencies controlled by Maori tribal authorities.

After MediaWorks took over, George poached DJs Nick D and Aroha from alternative station bFM.

George FM's low-powered transmission and alternative dance music fare has had a tiny audience

There is some programming crossover with bFM - which also has a small, loyal audience and has recently had a shakeup.

BFM is run by a non-profit trust and is not active in the commercial radio market. BFM spokesman Chris Hocquard said that George FM was attempting to be more like bFM, but he was not concerned by the change.

All radio broadcasters were facing a difficult advertising market, he said.

Hocquard said corporate ownership would inevitably change George FM on air but bFM would remain independent.