Internet simulcasting — a terrestrial station streaming its over-the-air signal online at the same time — has become the default for nearly every broadcaster in the United States and Europe. What began in the mid-1990s as an experiment by a handful of stations is now standard practice, and it has rewritten two things at once: who can hear a local station, and what that station owes for the music it plays online. The legal basis is a statutory license Congress created in the Digital Millennium Copyright Act of 1998, administered through royalties that do not apply to the over-the-air signal.
AA Digital Sound is a magazine about radio culture, not a broadcaster; this primer explains how simulcasting works, what it costs stations, and where it is heading, drawing on copyright law and documented industry practice.
What is the difference between simulcasting and an internet-only station?
A simulcast is the same program, at the same moment, on two delivery systems: the transmitter and the stream. An internet-only station — often called a webcaster — has no transmitter at all and exists purely as a stream. The distinction matters legally and creatively. A simulcast inherits the terrestrial station's clock, break structure, and local ads; a webcaster can program however it likes, skip the transmitter entirely, and in some cases serve a global niche too narrow for any frequency. Many broadcasters now run both: the FM signal simulcast, plus one or more online side channels — all-news, all-classic-soul, holiday music — that could never justify a license.
Why does streaming a radio signal cost more than broadcasting it?
Because U.S. copyright law treats the two signals differently. Over-the-air broadcast pays composers and publishers through performance-rights organizations, but pays no public-performance royalty to the owners of the recordings themselves. A digital stream pays both: the composition and a statutory sound-recording royalty for noninteractive webcasting, set through proceedings before the Copyright Royalty Board and collected largely by SoundExchange, the nonprofit designated for that purpose under provisions of the DMCA. Those statutory rates — set in five-year cycles, with per-song or per-listener formulas — are why a small station streaming a few hundred simultaneous listeners can face online music costs that rival its entire over-the-air budget. Public and noncommercial stations pay reduced rates, and small webcasters have at times had special statutory options.
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What does simulcasting do to a station's audience?
It removes the transmitter's border. A talk station in one city can now be a daily habit for a listener on another continent — the documented pattern behind diaspora audiences keeping home stations alive online. It also lets the audience choose the context: car, kitchen, phone, smart speaker. The trade-offs are real, though. Stream listeners are counted differently from over-the-air listeners, and most stream ad inventory is sold separately and cheaply, so a station can add thousands of online listeners without adding much revenue. Measurement firms treat streaming audio as its own ecosystem for this reason, and stations increasingly program for both audiences at once — the local listener in the car and the distant one on an app.
How has simulcasting changed what stations sound like?
Subtly but steadily. Many stations insert separate ad breaks into the stream so local over-the-air commercials do not run uselessly to a global audience. Some replace broadcast content that cannot be streamed at all — play-by-play rights for sports, in particular, are frequently blacked out online, a familiar frustration for stream listeners. Station clocks have been rebuilt around these drop-ins, and a generation of radio staff now thinks of every break as two products: one for the transmitter, one for the internet. The stronger long-term effect may be competitive: streaming put every terrestrial station in direct competition with on-demand audio, and it made station archives, replays, and podcast versions of shows almost free to offer.
Where is simulcasting heading next?
The documented direction points toward convergence rather than replacement. Most listening still happens on traditional receivers in cars, but dashboard systems increasingly treat FM and streams as one menu, and station groups have built their own apps and aggregated platforms to keep that menu from being owned by someone else. Hybrid radio — broadcast signal supplemented by internet-delivered artwork, metadata, and interactivity — has been deployed in several countries, combining the reliability of a transmitter with the flexibility of a stream. What looks least likely, on current evidence, is a mass switch-off of transmitters: simulcasting has mostly made the internet a second tower rather than a replacement for the first one.
What does it mean for listeners and artists?
For listeners, simulcasting means access — a hometown station kept for life, a genre signal from another country, a live show heard on a phone. For artists, it cuts both ways. A stream play generates a sound-recording royalty that an over-the-air play never did, which is why labels and performers have supported digital performance rights since the 1990s. At the same time, streaming costs push some small stations toward talk or toward reduced music hours. The balance keeps shifting with each royalty proceeding, and the stations in the middle — community, college, and small commercial outlets — feel every adjustment first.
Quietly, simulcasting has become the bridge between two eras of radio, and nearly every station now stands on it.