• by Erik Sass  @eriksass1, May 2, 2012

Satellite radio broadcaster Sirius XM has recruited a record number of subscribers, growing 8.3% to 22.3 million for the first quarter. Total revenues jumped from $724 million to $805 million over the same time period, the company revealed in its first-quarter results.

A large part of the company’s growth came from new vehicle sales and vehicle trial subscriptions converting to paying subscriptions, with 45% of all new vehicle owners deciding to convert to paying subscriptions -- the same as first-quarter 2011.

Looking to the future, Sirius XM CEO Mel Karmazin said improving car sales will continue to drive growth for the satellite broadcaster in 2012, projecting total subscriber growth of 1.5 million by the end of the year -- revised upwards from the company’s earlier forecast of 1.3 million net additions.

Subscriber churn, an important measure of the company’s stability, decreased slightly from 2% in 2011 to 1.9% this year, reflecting the increased share of vehicle-based subscriptions, which tend to be less volatile. Karmazin noted that churn decreased despite an increase in the subscription price.

Advertising revenues remain a fairly small part of Sirius XM’s business, growing from $16.6 million in the first quarter of 2011 to $18.7 million this year (remaining stable at 2.3% of total revenues).

Karmazin said the company hopes to woo new subscribers and retain existing ones, with a range of new content and features delivered via satellite and Internet: “We are rolling out more satellite channels via factory-installed 2.0 radios, and we are improving our online offering by delivering even more live sports coverage, updated apps with enhanced features, and later this year, on-demand content and personalized radio.”