Archives for October 2009

Upgrading to BBC iD

Tristan Ferne | 17:17 UK time, Thursday, 29 October 2009

BBC iD is the new sign in system for BBC Online. It's currently being rolled out across all services that require a user to register or sign in. But Radio Labs is in the vanguard and has already switched systems. So if you want to comment on the blog you will need to use the new BBC iD system. If you have an existing BBC membership, you can use your existing membername and password to sign in to BBC iD. The first time that you do this you'll be prompted to upgrade to a BBC iD and update and confirm your personal details.

You can read more and comment on the Internet blog and there is more help on BBC iD here.

Immersive audio for Planet B

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Caleb Knightley | 10:31 UK time, Thursday, 29 October 2009

Planet B is a science fiction series on BBC 7, the second series starts on the 29th November. You can read more about series two of Planet B on the Radio 4 blog.

Before you read on, you should put your headphones on and listen to this...

In order to see this content you need to have both Javascript enabled and Flash installed. Visit BBC Webwise for full instructions

With any luck you should have just had an interesting if not mildly disturbing sonic experience. And - by the way we don't really have your brain on a database; it was all just a sonic illusion..... As with all great Sci Fi special FX techniques it was done using a technique that was created a very long time ago and then re hashed in the 70s. The technique is called Binaural and has more or less been around since the dawn of broadcasting, when the French used it to broadcast operas though the telephone network to paying customers. It was originally patented in 1931 by Alan Blumlein as part of his pioneering research into Stereo for EMI.

Now if your not really interested in recording techniques you can stop reading now, as the rest of this blog will be as painful as sitting next to the really boring guy at a dinner party who talks about how the ABS in your car works...for hours. For those of you who are interested, you can read this and laugh at me, saying 'no, no, no - you so called BBC so called expert, you clearly have done it all wrong!'

Anyway, Binaural is a stereo recording and playback technique that tries to recreate sound in a three dimensional way. Surround sound for headphones. For true modern binaural recordings a 'dummy head' should be used with microphones placed inside replica ears, but there are a few variations on that theme. The basic idea is that two omni-directional microphones are placed a heads-width apart and are separated by a head-like object. So when listened to on headphones the sound appears as it would if you where really there. The drawback is that it only works on headphones and is in no way compatible with summed mono, i.e. the single speaker DAB radio in your kitchen. Also, as it is still just an illusion that tricks your brain, people can experience dummy head binaural in different ways. A common complaint being that all the sound seems to be coming from behind the listener.

A clever person has already written this wikipedia page on Binaural if you are interested in finding out more. And there's more on Dummy Head recording here. And a clear demonstration by a very nice chap on YouTube here. And there are other binaural shorts on You Tube including a virtual haircut which is fun;

BBC Radio Drama did an excellent play using binaural called The Revenge in the 70s with no dialogue. It's totally gripping and well worth a listen if you can find it. There are also many music recordings using binaural including some tracks on Pearl Jam's 'Binaural' album.

For the Planet B Immersive trail you just heard we actually used three different types of stereo. Those being 2 track Mono, L and R stereo and Quasi Binaural stereo.

The Quasi Binaural elements were captured in a few different ways. For the opening scene the voice of planet B says 'Thank you for choosing to upload your brain' while the probe moves around your head - we used two different techniques. For the vocal element I recorded the actress in a standard voiceover way with a Mono cardioid large diaphragm condenser mic; in this case a Neumann U87. This was then played back through speakers in the studio's live area positioned at opposite poles around a Jecklin Disk microphone array. (The disk was chosen over the dummy head for its better compatibility with data compression techniques).

The probe effect in the first scene was achieved by playing back the probe sound FX through a Fostex self powered speaker which was moved around the mic array manually. In the end it took three very quiet people to move the speaker, and my Phillips Shaver for extra intensity.

For the three scenes Spy world, Jurassic Adventure and Operation Extreme Glory, all the vocal elements were recorded using the Jecklin Disk, including the background voices in Spy World and the screaming soldiers in Extreme Glory.

The final binaural elements are the brain removal sequence. We again used the three person Fostex speaker dance for the sawing of the skull. The disk was then replaced by a melon and a coconut. These were operated upon with various implements and much fun was had by those of us listening on headphones to the squishing and scraping.

The rest of the sound design was done in L and R Stereo, and panned Mono using some spatial plugin's. It was all recorded, designed and mixed within the excellent Pro Tools HD. The in-studio SFX playback was done using Spot On play out software. We monitored using Sennheiser HD25-1s and Beyerdynamic DT250s. The recording console was a Studer Vista 6.

For me it was an interesting experiment in sound, combining different stereo techniques to create a unique listening experience. But really it was all down to the BBC Radio Drama Development team in coming up with such an excellent idea, and a brilliantly imaginative script!

Caleb Knightley is a Senior Studio Manager and Sound Designer for BBC Radio Drama.

What happens to The Proms after the Royal Albert Hall?

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Mark Kortekaas Mark Kortekaas | 16:17 UK time, Monday, 19 October 2009

Earlier this year, we broadcast another fantastic season of the BBC Proms. Every concert is broadcast live on BBC Radio 3, with some concerts also broadcast on television - mainly BBC Four, but also BBC HD, BBC Two and BBC One. That meant many live broadcasts live from the Royal Albert Hall - a building which is a number of miles away from Radio 3's studios in Broadcasting House. So how does the audio get from the Royal Albert Hall into my FM/DAB/Internet Radio at home? And what happens to it along the way? How much is the audio in the Royal Albert Hall "dynamically compressed" (where the quiet bits get louder and the louder bits get quieter), and is any of the audio signal chucked away by using bandwidth limiting? And how might you get the best quality from our Proms coverage? I've always been interested in this; so here's what happens: For Radio 3 transmission, on iPlayer and others
  • The Radio 3 stereo mix is sent from the Albert Hall to Broadcasting House via a high-quality 24-bit 48 kHz digital circuit and then fed to Radio 3 FM, DAB, Freeview, Freesat & Online services. The microphones within the Royal Albert Hall handle frequencies from a few Hertz to over 20kHz and there is no LF or HF filtering added to the main microphone feeds.
  • Radio 3 FM is bandwidth-limited to 15 kHz, with DC filtering applied. The FM signal has dynamic range compression applied via an Optimod processor. The signal is NICAM encoded at 676kbps and fed to the FM transmitters via the BBC's distribution network. No further bandwidth limiting is applied.
  • The feed from the Royal Albert Hall is also fed to Radio 3 on DAB, Freeview and Satellite. These operate at 192kbps, although this reduces to 160kbps on DAB at some points in the schedule to accommodate 5 Live Sports Extra on the DAB multiplex. There is no other processing applied to the signal.
  • On the BBC iPlayer's listen-again services, Radio 3 is available at 192kbps AAC. This is processed in the same way as DTT ("Freeview"). Live streaming is also available, at 192kbps Windows Media and other versions.
For BBC Four transmission
  • BBC Four uses the same stereo mix that's used for Radio 3. It's combined with the pictures and sent back to Television Centre via an MPEG2 (MPEG1 Layer II) link at 384kbps. No additional processing is carried out before encoding.
  • BBC Four sound on Freeview, Freesat and Sky is transmitted (using MPEG2) at 256kbps with no processing or bandwidth limiting.
For BBC Two and BBC HD (also BBC One) transmission
  • Proms on BBC Two (and BBC One) use a dedicated sound mixing truck, to ensure that audio is mixed in a complementary way to the pictures broadcast. Proms also transmitted on the BBC HD Channel are usually mixed in surround sound using Dolby 5.0, though broadcast in Dolby 5.1 for technical reasons.
  • Stereo for BBC One, BBC Two and BBC HD is sent back to Television Centre via an MPEG2 (MPEG1 Layer II) link at 384Kbps.
  • When available surround sound is sent back in the same link using Dolby E encoding at 2Mbps (Dolby E can support up to 8 channels).
  • Stereo is transmitted on BBC One, BBC Two at 256kbps (MPEG2), and 256kbps (MPEG4) on BBC HD.
  • Surround sound is transmitted on BBC HD at 384kbps using Dolby Digital encoding. Dolby Digital has a frequency range from about 3 Hz to 18 kHz.
  • Only the surround sound mix is transmitted on BBC HD. If an HD set top box is set to "Stereo" it uses the additional data (Dolby Metadata) we send in the Dolby Digital signal to create a stereo mix.
  • BBC television analogue services use NICAM-728 encoding the stereo signal at 728kbps for transmission.
Of course it should be noted that various transmission chains have their own issues depending on the output. For instance the Freeview signal is MPEG coded, filtering happens as part of the coding process, in a 32 segment polyphase band pass filter. The AAC encoding does its own thing, etc. With that in mind, the feeds are really filtered to you as the end listener. I'm grateful to Andy Quested from BBC HD, and Neil Pemberton from BBC Radio 3 for compiling these answers.

RealMedia - an update

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Mark Kortekaas Mark Kortekaas | 15:23 UK time, Wednesday, 7 October 2009

Editor's note: this is a joint posting from: Mark Kortekaas (BBC Audio & Music), Ian Myatt (BBC Nations & Regions) and Karl Kathuria (BBC World Service)

At BBC Radio we try to deliver the best experience for users of our streaming services. We constantly review our services to make sure they deliver 'public value'. The four drivers of public value are: Reach, Quality, Impact and Value.

When streaming services are evaluated against these measures, we take into account where different formats might need to be implemented, evolved or deprecated.

The streaming service provided in RealMedia format has been with us at the BBC since 1996. At the time it was the best option available, but more recently alternative methods of delivery have become just as important. These include Windows Media and Flash.

When evaluating services with our public value tests, which includes the costs of the services, we came to the decision that RealMedia was something we needed to phase out.

The actions to phase out RealMedia are broken down as follows:

  • National networks - e.g. Radio 2, Radio 6Music, Asian Network, etc
  • Nations - e.g. BBC Radio Scotland , BBC Radio Wales, etc
  • Local Radio - e.g. BBC Cumbria, BBC Bristol, etc
  • WorldService - the English language streaming service in iPlayer only - international World Service streams are unaffected.
National networks

It was clear that we could easily plan for a migration period for National networks during which RealMedia and alternatives will be available and allow for our audience and third-parties to make changes in a reasonable period.

So we'll be phasing out RealMedia by 30 March, 2010 for National networks.

In order to improve the experience in the BBC iPlayer web interface, we'll change the lower bandwidth option from its current RealMedia offering to a new Flash offering at 48kbps. We hope for this to be completed in October.

The legacy RealMedia streams will continue to exist on our systems until the March deadline, so that it gives those who still use them time to migrate to using the alternative:

  • Windows Media for Live streams - available globally for these services
  • Windows Media for Listen Again streams - will phase in over the next few months and be available globally.
Nations & Local Radio

The technology used for Nations and Local Radio services is more restrictive and a more difficult decision had to be made. A migration period would not have been possible without a significant increase in equipment which could not be justified. We had to make the unfortunate decision to switch off RealMedia as we simply could not offer both RealMedia and Windows Media at the same time.

In addition to the disruption caused to the Listen Live services, an unforeseen dependency means that the Listen Again service in Windows Media won't be operational until November.

World Service

Due to differences in production, World Service live and on-demand streams will continue to be available in Flash, RealMedia and Windows Media formats. However, if you access our content through BBC iPlayer it will only be available in Flash. Links to RealMedia and Windows Media versions of our programmes will be available from

Mark Kortekaas is Future Media Controller, A&M and Mobile Media

Further help

Fun with Quartz Composer in Snow Leopard and the BBC Radio Schedule

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Duncan Robertson Duncan Robertson | 12:20 UK time, Wednesday, 7 October 2009

Quartz Composer [QC] comes as part of Apples Developer Tools on OSX. It is described in Wikipedia as 'a node-based visual programming language'.

I think the easiest way to understand it, is it lets you plug things into other things to produce very cool things, without the need to write a single line of code. These things are called patches and Apple provide a whole library of them (even more in Snow Leopard). These patches wrap low level functionality in them like OpenGL , Core Image, Core Video, Bonjour Services, Apple Remote Access, Midi, XML loading and parsing etc, without you needing to understand the underlying technologies. You can also write your own patches including the ability to incorporate JavaScript to effect the patches results. A patch is like a function, you pass it some information and it returns results, without you needing to care what happens inside.

So, with all these patches, you create a composition, which is a file with a .qtz extension. Here's an example of what a composition looks like:

Quartz Composition

A composition can be ran stand-alone, exported as a QuickTime movie, or used in a Cocoa application. It can also be used as a Screen Saver or iTunes visualization simply by dragging it into the correct folder on your Mac. A patch can also be nested in a patch, so as you can imagine the compositions can get quite complex.

One of the limitations of the initial version of QC was that you could only load RSS feeds and not arbitrary XML. Luckily this had been addressed in the new version, so as well as all the other awesome new patches, there's one that lets you provide a path to some XML, and handles downloading and parsing into a structure, as well as download progress information and a flag for when the data is ready.

With this new functionality as well as other new patches, I have created a composition that rolls through the BBC's National Radio networks and displays who is currently on air, as well as downloading and displaying the network logo and a pretty image for that show. Here's a screen grab:

Quartz Composition

You can download the composition here:

To install you need to:

  1. Make sure you are running OSX 10.6 (It won't work otherwise)
  2. Unzip the downloaded file
  3. Move the BBC Radio Now.qtz file into your Screen Savers directory.
    /Users/<username>/Library/Screen Savers
  4. NOTE: You may need to create the Screen Savers directory if it doesn't exist

Now you can go to the Screen Savers settings page in system preferences, and you will be able to choose BBC Radio Now from the left hand menu. You can also adjust the duration in which the radio stations are switched via the options tab. Oh and remember, if you're not connected to the internet then you won't see anything.

Disclaimer: I made this as an unsupported demo for my own learning. If you find any problems and fixes, please post them in the comments

What's your musical taste?

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Tristan Ferne | 12:08 UK time, Friday, 2 October 2009

I’ve been thinking about musical taste and how to describe it so I asked the team here “…to describe your musical tastes, however you like, and then send/give it to me”. Responses ranged from Spotify playlists to descriptions to diagrams and I thought they were interesting enough to share.

From in-depth description …

"Some bands in no particular order: The Beatles, Elvis, Bowie, Talking Heads, Elvis Costello, Jonathan Richman, Orange Juice, Iggy Pop, Velvet Underground, The Specials, The Only Ones, The Clash, Radiohead, The Pixies; generally I like all Punk and New Wave (especially the one-hit wonders) between 76 and 84 - after that the horror of the New Romantic era put me off listening to music on the radio; another strand is early 60s girl bands like
The Shangri-Las, The Crystals, The Shirelles - well, all of them really; also a big fan of Louis Jordan and that whole 40s jumpin’ jive sound. I used to do the Camden live music pub circuit, both playing and to listen to the other bands. My classical taste is limited, though I know I’m more Beethoven and Bach than Mozart or Schubert.

"Interesting… when I started thinking about my taste I often like specific artists, but not necessarily the whole genre they’re in, e.g, in jazz music I like Monk and Bill Evans, in jazz funk I like Herbie Hancock and Mahavishnu Orchestra. In dance music I like specific DJs like Sasha, John Digweed, but not Judge Jules or Pete Tong. Here it’s the DJs that are important, more than individual artists and producers. Deep house and garage - the early-mid 90’s US variety, not the later UK garage, or any of the other myriad garage genres. I like Tangerine Dream (before they went bad in the mid-90’s) and Klaus Schulze - “Berlin school” electronic music. What else? Classical music - Bach, Mozart, Beethoven (but more the string quartets than the symphonies)."

To brief ones…

" Eclectic, Eccentric and Elitist."

Then there was a bootleg album cover with "Lou Reed at a tacky Adelaide hotel (with - I think - Malcolm Young from AC/DC) after the first (and best) concert I ever went to". Or more visual representations…

Connecting moods and music

"Here’s a stab at my taste. I realise that my taste is pretty much completely mood based. I have used genres to stop this taking months. I also kept it top level, as I could also have joined things like “Happy” and “Busy” together to produce a different result."

Connections and influences

“I had to stop at some point so it’s not comprehensive. But it’s all about connections”

Record diary

“If asked i’d show people last fm i suppose but thats not entirely accurate.this is a bit more reflective [a spotify playlist of my 500 favourites] and this [photo above] is highly accurate for one period in my life - my record diary when i was 13-17. or in least today I like late80sindiepop,beatles,sunshinepop,folkrock,northernsoul,ska,late70sandlate80shiphop,70sdisco,abba,spectoresquegirlgroups,and cilladustysandieuk girlgroups, the first 50 releases on creation, roughtrade, postcard, 4AD, and Mute and lots of versions of Amazing Grace.”

Graphing taste

"I like nothing from before 1960. First attempt had 1930 as year zero, but I realised I didn’t like anything from then! X axis shows when the music’s from, Y axis shows the time I first liked the group. I have been ruthless about exercising things I don’t like anymore. This isn’t to show how cool I always have been, but because this is a snapshot of ‘now’"

Obviously this is a small and select sample but some common themes emerged. About half were discursive and half were visual in some way. Most people mentioned specific bands or artists and musical genres, followed by record labels, songs and albums. There were lots of tag-like descriptions, “early 60s girl bands” for instance, identifying more niche genres or scenes and also mood-like descriptions. And there was quite a lot of personal history, obviously your taste changes over time. Also interesting was that some people defined their taste in terms of dislikes.

Paul over at the Music Machinery blog noticed I’d posted my musical taste to Flickr and he asked his readers to send him their representations of musical taste. So I thought I’d do the same over here. What are your musical tastes? How would you best describe them? Do you feel comfortable telling us? Is it too hard to describe? Answers in the comments or on Flickr (tag them MyMusicTaste) please.

BBC Radio Waves - exploring what we play

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Tristan Ferne | 12:09 UK time, Thursday, 1 October 2009

What kinds of music does BBC radio play? Which bands are played most? Which DJs play 70s music? Radio Waves is a prototype visualisation that takes data about music played recently on BBC Radio and creates a time profile for any individual radio network, musical genre or radio show. The graph shows, year by year, how many albums were released by the artists recently played on BBC Radio.

BBC Radio Waves

Click here to explore the visualisation or read on to find out more.

After our recent hackday on music visualisation we ran a quick two week sprint with the R&D Prototyping team to develop a combination of the best and the most feasible of the ideas that came out. Radio Waves is the result of that sprint.

What it does

Initially the visualisation represents all four of the BBC radio stations we are using; BBC Radio 1, BBC Radio 2, BBC 1Xtra and BBC 6 Music. The graph represents how many albums were released by the bands and artists recently played by shows on that network - so if it has a peak in the 1950s then that network has played artists who were active in the 50s. The visualisation can then be filtered to show the graphs for a particular radio network, a genre or show. BBC Radio Waves - Steve Lamacq - 1995

Individual years within the graph can be selected to show a list of artists who released albums in that year and have been most played by the selected radio network or show. Clicking on an artist will show more detail about them and reveal the complete list of albums they released and when.

How it works

We start by collating the data for what music BBC Radio has played over the last few months - from tracklistings like this. Note that this prototype is only using a static data set for now. From this we can link to /music data about these artists, and from there to releases from each artist. From the complete list of releases we try to only use albums, not compilations, EPs or singles, as we believe that albums sufficiently represent an artist’s historical profile (this is arguable). We can then take the release dates of all these albums, and the number of times each artist has been played on that radio network or show, to draw the graph. In total we're using about 300 shows, each with a play count and top artists for every year and a list of about 9000 featured artists.

We have to tidy up the data a bit; not all tracks played have MusicBrainz IDs attached, we have to remove duplicate releases (there are lots of “disc 1” and “disc 2” in the MusicBrainz data) and we also remove any albums from “Various Artists” because that's not particularly helpful for our purposes. And we've left out Radio 3, Asian Network and the regional services because we don’t have that much play data from them at the moment. Radio 3 in particular would be difficult because the "releases" they play don’t represent a composer’s active career in the same way as releases for pop and rock bands do.

It’s a prototype

Radio Waves was built so we could explore the possibilities of visualising our music data and we deliberately constrained ourselves to only use data that we have available right now. We think it has one major but surmountable problem. Our current architecture and data mean we can only go from a show » songs » artists » albums » release dates. So this doesn’t actually represent the release dates of the music that is played on the radio, rather it represents the careers of the artists whose music is played and that’s not completely intuitive. Ideally we would go directly from show » songs » release dates, and at some point, with the help of the MusicBrainz next-generation schema and some dedicated volunteers, we should get this data.

BBC Radio Waves - Elvis

As an end note, we probably also need to tidy up which album releases we use. If you look at the graph for Elvis you can see his original career (he reportedly died in 1977) and then a resurgence in popularity (and therefore re-releases, sessions, best-ofs…) in the last decade. So maybe we should limit the data to releases within the artist’s (or bands) lifetime.

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