Radio vs. Digital vs. “Real Music”?
2013-07-25 — Original posting (on Blogger)
2014-11-09 — Re-posting as is (WordPress)
2016-07-13 — Brushed up for better readability
Posting #101, on the occasion of reaching 30,000 visitors to the blog — thanks to all readers for that many visits: this is an excellent motivator to continue!
- Analog Radio vs. Digital Recordings
- Channel Separation, Dynamic Range
- Radio vs. Podcast vs. DAB(+)
- Previewing Digital Recordings
- Full Quality Digital Downloads / Previews
- Conclusions / Recommendations:
Analog Radio vs. Digital Recordings
Recently I was listening to a CD comparison on the radio (in the form of a podcast). I wanted to verify the findings of the discussion members, as well as my own impressions. I did this by by listening to a longer section of the piece under discussion from my (digital) library. It was the very same recording in my collection, i.e., its ripped tracks in my electronic library. My library uses Apple’s lossless compressed format, i.e., its audio quality should be identical to the one on the original CD.
Channel Separation, Dynamic Range
I was well aware of the fact that analog radio stations are using compression in order to keep their radio signal within the licensed frequency bandwidth (particularly in Europe with its high density in radio transmitters, using a frequencies spacing of 100 kHz only). But even in Europe this should allow for an audio bandwidth of 15 kHz — not that much below the typically 18 kHz available in standard CD recordings. That presumably should be acceptable for the majority of the listeners. But audio frequency is not the only concern. The analog broadcasting also restricts other audio features. In the direct comparison it was amazing to hear how much the channel separation, as well as the dynamic range, suffered in the radio broadcast:
- Channel separation: my impression was that there is about as much difference between “CD stereo” and (analog) “radio stereo” as there is between the latter and a mono recording. The spatial width and resolution were clearly reduced on the radio.
- Also the dynamic range was clearly more limited. The piece in question may have been demanding (I think it was Hector Berlioz’ Requiem op.5). However, the radio clearly has limitations in reproducing a proper ppp as well as fff!
Radio vs. Podcast vs. DAB(+)
None of this should have been news to me. Still, it was amazing to hear how big the restrictions are. Many European countries (including the one I’m living in) are now also offering digital audio broadcast (DAB or DAB+) — but most or all of them still also serve analog FM channels, and as long as that is the case I doubt that these are yet offering “true digital quality”. If this was the case, I would expect podcasts to offer “digital quality” rather than just digitized analog radio, and that clearly is not the case in Switzerland. I’m exaggerating slightly: the bulk of the radio production is handled digitally these days — but that doesn’t mean much in terms of quality, obviously!
What lessons did I learn from this?
- Radio broadcasts may give a reasonable impression about an interpretation, but they can hardly be taken as indicative for the audio quality of a given recording.
- Recording / ripping audio broadcasts (or storing excerpts from podcasts,where appropriate) is likely a really poor substitute for a “real” recording (CD, high quality audio download).
Previewing Digital Recordings
Are there alternatives for previewing a recording? It’s not easy: with many (most) download sites, audio previews (if present at all) are either very short (30 – 60 seconds), or they are poor MP3 quality (e.g., 32 or 64 Kbps) — if not even both! CD shops where you could listen to longer samples have essentially ceased to exist.
Full Quality Digital Downloads / Previews
Magnatune (www.magnatune.com) does offer full quality / full length previews. These include “spoiler ads” that one cannot remove without crippling the audio tracks. Fair enough, but then they have that strange subscription model, which may not be to everyone’s taste (unlimited downloads for subscribers). Also, their repertoire is limited, both in terms of music and artists.
YouTube offers free viewing, but the audio quality is typically fairly modest, even if it’s not an amateur recording. It may give a good impression on an artist’s abilities and performance style. If it is a live recording, it will usually be quite different from a studio recording, not just in the sound quality.
For myself, these findings don’t utterly worry me. It’s just good to know, but for the true audiophiles out there things may be a bit tricky. For me, the interpretation is far more important than the ultimate audio quality. My ears are not the same as when I was 20 anyway! In my opinion, what the sound engineer messed up during the recording sessions cannot be corrected. Not even with 20- or 24-bit ADCs, SACD, and perfect, expensive audio equipment. Microphone quality and placement, sound balancing, and the acoustics of the recording location are key to a good recording. The rest is “good to have”, but not really prerequisite (again: audiophiles may not agree here).
Conclusions / Recommendations:
- get to know your artists! Artists that you are familiar with, and whose interpretation / taste / attitude you trust can guide you into repertoire that you are not or less familiar with. This way, new CD recordings are less likely to be disappointing.
- look for trustworthy labels! There are some small labels (ECM comes to mind) that may have a small, restricted repertoire only. These are often able to produce consistent, good quality recordings. They may feature a small, but excellent selection of artists (and composers). And they are less likely to disappoint than selecting an arbitrary recording from the huge production of one of the market leaders.
I don’t mean to imply that big labels don’t produce good recordings, too. I have many excellent recordings from labels such as Harmonia mundi, Virgin classics, DG, Decca, EMI, SONY, etc. — but when you don’t have the chance to preview (particularly if you don’t know the artists), the label may not be the best guide when trying to explore unknown repertoire or artists.
- the price of a recording on CD is not a guarantee for satisfaction. It’s maybe an indication that you might get a decent booklet, cover, etc. — but the price might just as well be mainly market hype!