The tech behind U2's record-smashing tour

The Edge and Bono perform before 96,000 fans during the U2 360 concert Sunday at the Rose Bowl in Pasadena, Calif.

(Credit: Daniel Terdiman/CNET)

PASADENA, Calif.--If you were one of the 96,000 people packed into the Rose Bowl Sunday night for the U2 concert--said to be the largest concert ever held here--you were sharing the experience with at least a few other fans off-site.

There's no way to know yet how many exactly, but it's safe to say millions of people around the world were also watching the concert live on YouTube, a potentially server-crashing Webcast that may have been the biggest live-stream yet.

For months, the band has been on tour with its U2 360 concerts. And to top off the grand claims, it has been called the biggest rock tour in history, at least as measured by the size and cost of its infrastructure--more than $750,000 per show, according to Rolling Stone.

Only days ago, the band announced that it would share the Rose Bowl concert live, with fans across the globe. Just before the band came on stage, a roadie calling himself Rocco got up in front of the crowd of 96,000 and said, "Tonight, you are the ones making history," shouting out that those in attendance would be joined by viewers in "North America, South America, Europe, Africa, Asia, Australia, and Antarctica."

Photos: U2 goes global via YouTube

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For its part, YouTube wasn't sharing much about how it put together the live stream. Before the show started, there was some discussion among reporters on hand at the Rose Bowl about whether YouTube would be up to the task of delivering the show to so many people, live, on so many continents. But if Twitter is any judge, the live-stream went off almost without a hitch. More to the point, a Twitter feed set up on the official YouTube U2 page showcased comments in a wide variety of languages from Webcast viewers.

Back at the Rose Bowl, in an effort to rally the capacity crowd, the concert-goers were told why this show was chosen by YouTube: "Because right here is where the greatest singers of U2 songs are....Tonight, we need to hear your voices, and to hear you sing. Can you do it?"

In response, the crowd roared its agreement, and indeed, throughout U2's approximately two hours on stage, there were several emotional moments when U2 leader Bono stopped singing and let the audience take over the vocals. These were truly beautiful and awe-inspiring moments, as there is very little on Earth like the sound of nearly 100,000 people singing together.

Ironically, no connectivity
These days, you can find out what's happening at just about any event by turning to Twitter. But at the Rose Bowl, this wasn't the case. It turned out that there was nearly no connectivity, and so there seemed to be a dearth of tweets sent from inside the concert. Still, because the show was being watched by millions of people around the world, there is certainly no shortage of posts on Twitter about what was happening.

That's an ironic turn of events, though, and not at all what I expected. I thought there would be a steady stream of tweets emanating from the Rose Bowl, and I had expected to send many of them myself. Instead, this highly tech-centric concert was ground zero for a disconnected audience. We were truly "stuck in the moment," to quote one of U2's hit songs, though I doubt anyone wanted to "get out of it."

A YouTube representative did tell me prior to the show that the service was using 24 cameras to film the concert, as well as 24 additional closed-circuit TV cameras. Further, he said YouTube was offering its stream at three different qualities, so that almost anyone could watch, regardless of the speed of their Internet connection.

The YouTube U2 page with the stream of the concert, albeit a rebroadcast. But millions around the world watched the Rose Bowl concert live on YouTube.

(Credit: YouTube)

Having YouTube produce such a major Webcast is fitting, given the size and scope of the U2 360 tour. Among its facts and figures are tidbits like this: the 360-degree stage--which allowed huge numbers of fans to watch from behind--featured a 90-foot-tall steel structure, topped by a center pylon reaching 150 feet in the air; the innovative video screen atop the stage weighs 54 tons, is 4,300 square feet when closed, and is 14,000 square feet when opened; the screen itself is comprised of more than a million pieces, including components to illuminate 500,000 pixels, as well as 320,000 fasteners, 30,000 cables and 150,000 machined pieces.

The incredible expanding screen
The video screen, according to information provided by the band's publicists, is "broken into segments mounted on a multiple pantograph system, which enables the screen to 'open up' or spread apart vertically as an effect during different stages of the concerts."

I didn't think I'd ever seen such a thing before, and it just about made my jaw drop when I noticed it. Already, the screen was a sight to behold, but it didn't seem all that big, especially when I thought back to what I'd seen the band do with video during its U2 3D film.

The U2 360 video screen featured an expansion system that allowed it stretch to a size more than three times what it is when closed.

(Credit: Daniel Terdiman/CNET)

Well, it turns out I was right: I hadn't seen anything like this before, and neither had anyone else who hadn't been to one of the U2 360 shows.

"The video screen is the first LED screen to be based on a geometric system that allows it to expand in two directions simultaneously," U2 360 architect Mark Fisher told CNET News in an e-mail interview. "Video screens are normally flat panels that track like closet doors, or slatted panels that roll up like garage doors. The 360 degree screen uses a scissor-like motion to expand in two directions. It starts as a solid elliptical ring approximately 20 feet deep, and transforms into form a cone-shaped mesh 60 feet tall."

Fisher added that this is the first time such technology--what he called "transforming geometry"--has been used to "change the shape of a video screen."

And while Fisher said that, in general, the technology behind U2 360 isn't in and of itself new, the way it's being used during the tour most certainly is.

"The show employs a large number of computers and electric motors to control the motion of the screen, and there are large numbers of computer-controlled moving lights," Fisher said. "The video on the screen is also created using powerful computers that 'map' the picture onto the transforming screen. All of this automation and programming is possible because the computers available in 2009 and more powerful, and cheaper, than they were when we created the Vertigo tour in 2005."

Google Earth
Another piece of technology used for the tour--at least in a way that U2's fans can interact with--is Google Earth. Fisher explained that the stage's designers decided it would be fun for fans to see the huge structure on Google Earth.

"So we hooked up with the folks that run the operation, and they agreed to let us put 3D models of the stage into the 3D models of the stadiums where it plays," Fisher said. "The 360 degree stage is turned around in each stadium in six days (and) the models stay in each city on Google Earth for slightly longer."

U2 used Google Earth to give fans a sense of how the stage in its U2 360 tour was built. Here is the London site.

(Credit: U2)

On U2's official Web site, the band explained what is going on with the Google Earth project: "If you're following the tour as it moves around...there's a very cool new feature on Google Earth--a model of the 360 stage, in situ, at the venue, about a week ahead of each show."

The site also explained that the model that fans see could be red, green or blue, with each color corresponding to one of three "steel teams" that "leapfrog each other from city to city to build the stage in each stadium."

Fisher also weighed in on the site with the real reason why the band chose to implement Google Earth: "We thought it would be interesting to put up on Google Earth a piece of portable architecture, which is what this structure is," he wrote. "In a way it's got no practical purpose...except that it's fun!"

[MyRightEye]

Was great to see Bono and 96k people worshiping God last night.

[Paul_Christie]

lol. Your comment was funny for some reason...
I think its the way it was phrased.

[esierra1]

You mean it was great to see Bono and 96K people worshiping Bono, right?
:-D

[alstatr]

I saw U2 on 9.12.09 in Chicago and it was amazing. I also watched last night and I too intended sending some tweets but I was to busy enjoying the concert. It was cool to hear a few different songs from the set list they played in Chicago. If you thought the video screen was amazing on the youtube stream, it was even more jaw dropping in person.

BTW I would have gladly paid a small fee ($8-10) to watch the concert, maybe this could be a new revenue "stream" for bands and youtube...

[dbargen]

On Paying for Concert Streams:

Much of what a concert event is about is high quality live audio. Do we even have streams of that bitrate available via YouTube?

[alstatr]

I thought the audio quality was pretty good, I was streaming at 1000kbps.

[J. Blow]

Um, yea, another band ******** about the environment yet wasting an enormous amount of power for their show. Nevermind the fuel used just to move their crap from one venue to the next.

The hipocracy is mind numbing.

[alstatr]

I don't know about waste, I guess that's a matter of opinion. I do agree that their message of being net zero emissions is lame. There is no way they can make up for all the electricity used in their shows. I doesn't matter that much anyway because the climate is changing without our help.

[ikramerica--2008]

If you care about this sort of thing, which bands like U2 claim to, it's hypocrisy. "carbon footprint" is enormous, and no amount of tithing to the religion of environmentalism via creating net zero emissions trickery changes that they could not hold the concert, still do the "green" stuff, and make a positive impact instead of a net zero one.

[cosuna]

"...as there is very little on Earth like the sound of nearly 100,000 people singing together. "

Maybe, just maybe... that is the true voice of God...

Been a U2 fan since 1988 and I'm hoping they'll return to Monterrey soon. In the mean time, have to watch on "U2ube" (sic, from U2.com site)

[sting7k]

For someone who goes on and on about the environment I really can't believe the resources they put into moving this thing around so often. Is Bono planting trees some where to offset the carbon this stage generates each time they move? How much power does it use?

[AppleSuxLeo]

Smashing Pumpkins with a side of Cranberries please.

[Xtoo]

I can take or leave U2... but don't hate what the band and Bono have accomplished on and off the stage.

[ikramerica--2008]

This concert was two miles from me. Could hear it from my place. They blocked off all these side streets about 1 mile away that they don't block off for the Rose Bowl, and towed a bunch of cars in front of their own homes, even on streets where they didn't put up temporary no parking signs! But this event was no bigger than the Rose Bowl game, so what's up with that? Why did U2's people find it necessary to inconvenience the city of Pasadena's residents in this way when all other event organizers can do it better? And how much did they pay our police force to do this? And can people who had their cars unjustly towed send the bill to U2?

[dennisl59]

The Biggest Surprise?...The Edge can still form a basic "G" bar chord...what fantastic musician!!!

[luke_marsh]

With music It's vital that the Engineers and boffins act well to bolster the music industry. Later More artists will need to be brought to take advantage of cultural change and new thinking with a new keen eye for art being born.
It's called breaking away from the old model and the Music industry has more guts in many ways than the movie/television industry for this and is more flexible given the Internet model and capabilities of the net at present.
This is not someone controlling the back drop so much as it is timing and how long it takes for things to develop and occur. True the world market could be expanded right now and the stock and work market would fly as a result and some might argue that would be enough wind but really there is Progress issues and intelligence equilibrium issues. In other words man needs to evolve and it will take time. If the peak drops badly as a result of man incompetency at this the market can be altered to compensate.
There's the difference I'm not looking to feed off bad times to make myself look bigger I'm looking at the complexity of now which can appear like control but it actually goes deeper.
I'll work it from false economic ground, undervaluation or a fair straight line market plane I don't care the Economy must go on.
The biggest concern at the moment is a depression momentum causing a cancer from a blood clot in the financial district leading over time to ill economic health.

[romulus19]

I was at the concert and during the break between the Black Eyed Peas and U2 tried to connect to facebook - I had no service on my 3GS. Although that is not unusual for this device, I thought perhaps the cell towers in the area were overloaded with an additional 100,000 people in that locality. Reminds me of what happened at the south by southwest film festival recently.

[NervClaX]

Listening to U2 makes me want to watch "Blown Away" with Tommy Lee Jones and Jeff Bridges. And Jeff Bridges makes me want to buy Duracell. And Duracell, the most trusted brand according to Jeff Bridges, makes me want to waste some electricity and not recycle the battery. So U2 is definitely having a negative impact on the environment as far as I'm concerned.

[boyatheart]

I was really impressed with the quality of this webcast. What proves the magnitude of the excellence of its delivery is tha fact that the quality of the production, including the fact that it was free of technical hitches was so high I imagine most people didn't even think about just how much must have been frantically going on behind the scenes while we watched a uniterrupted show.

Credit to the engineers, organisers, programmers and runarounds who were involved. Even on my mediocre broadband connection (I'm in SE Asia), it was a joy to watch, only pausing to buffer the video a handful of times for a couple of seconds.

I'm excited because I'm a recording artist who would like to extend my reach playing live and in the not too distant future I imagine that the technology in use for the U2 webcast will be much more accessible to those with more modest budgets.

[nataliev39]

This concert was a brilliant idea. I also think that the comment about a disconnected audience was very interesting. There was no lack of Tweets about the concert., but not as many coming from inside the Rose Bowl. A disconnected audience means that the concert had the ultimate affect on the fans. The idea that this awesome concert was shown to anyone who wanted to watch it, is such a gift. I think that there should be more major live streams like this.

[owlflavored]

Doesn't sound like Natalie was actually at the show.

But as someone who was, and has been to many UCLA games at the Rose Bowl, I can tell you that the Arroyo that the RB sits in is Death Valley for mobile phones. I was shocked I actually had bars on my iPhone 1.0. I was able to make one phone call, but no texting/internet usage.
My buddy who has the newest iPhone was equally frustrated.

For the first-time U2 concert-goer, I'm sure it was amazing, but it was my 13th show, and easily a lower-tiered one. The band looked tired and they played to camera, v. the audience.