View Full Version : FM vs. Digital Radio

2006-01-03, 11:16 PM
I have received word that recordings from digital radio are technically superior to recordings from regular FM radio. The reasoning behind this is that "FM compression negatively alters sound quality far more than the streamed mp3 lineage." What is the validity to this statement? I know of course that both broadcasts are compressed, but what is the lesser of the two evils? And the SA of two samples from both sources point to FM as being the superior recording. Digital radio broadcasts are broadcast at 192 kbps, but what is the approximate bitrate of an FM recording? I've read anything from 96kbps ( :confused: ) to 256 kbps. Thanks.

2006-01-04, 03:13 PM
And the SA of two samples from both sources point to FM as being the superior recording.
Thing is that you usually listen to your recordings, rather than watching their SA. ;)

That aside, short answer: Depends.

Long answer: Unfortunately this is not entirely a "black & white" issue. The final quality of each recording depends on a lot of factors. For example the quality of the FM broadcast depends on the quality of the reception, on the source of the broadcasted audio (remember that it might just be a decoded version of the digital broadcast stream), the gear used for recording on your end, etc. On the other hand the quality of the digital (mp2) stream depends heavily on the bitrate (even though 192kbps seems to be the most common bitrate at the moment, a digital radio broadcast can actually have 128-384kbps) and the quality of the mp2 encoder.

Generally digital broadcasts do have an edge though, because given enough bitrate (preferably 256-384kbps) it's relatively safe to assume that they'll sound better than FM. No reception / noise floor issues etc.

2006-01-04, 05:15 PM
well, analog FM is dynamically squashed quite a bit and everything above 15kHz is pretty much gone. so its sorta like a little below 128kBps cbr mp3 in terms of frequency cutoff. but lame also digs in an removes stuff below the cutoff that the encoder figures you won't notice is missing. but the dynamics aren't crushed. so there's sort of a tradeoff there. would be great to hear samples of the same broadcast in analog & digital and have a little listen. When I think of digital radio I think of lossy webcasts and rm and such and that's probably not fair.