Inside Track: Queen 'Bohemian Rhapsody' Soundtrack

Left-right: Gwilym Lee (Brian May), Ben Hardy (Roger Taylor), Rami Malek (Freddie Mercury) and Joe Mazzello (John Deacon) recreate Queen's legendary Live Aid concert in Bohemian Rhapsody.Photo: Twentieth Century Fox

The highlight of Queen biopic Bohemian Rhapsody is a meticulous recreation of their most famous live show — using a fresh mix of the original audio recordings.

By the time you read this, Bohemian Rhapsody may well have grossed more than one billion dollars worldwide. It's already the highest-grossing musical biopic of all time, by a factor of five, and the highest-grossing drama film without action or fantasy scenes. Rami Malek has been widely praised for his astonishingly believable portrayal of Freddie Mercury, and at the time of writing, the movie had just won four of its five Oscar nominations. Queen manager Jim Beach produced the movie, and guitarist Brian May and drummer Roger Taylor were involved in almost all aspects of its making — which took no less than eight years.

The music of Queen, of course, is central to the film's success, and the band's original recordings were used almost throughout. The soundtrack has been honoured with a BAFTA Award for Best Sound to John Casali (production sound mixer), Tim Cavagin (re-recording mixer), Nina Hartstone (supervising dialogue editor), Paul Massey (re-recording mixer) and John Warhurst (supervising sound and music editor). The movie also won Academy Awards for Best Sound Mixing and Best Sound Editing, and the quintet clearly performed miracles with the dialogue and in putting the final movie sound mix together. The original Queen music, however, was supplied by the band's own sound team, consisting of Justin Shirley-Smith, Joshua J Macrae and Kris Fredriksson. May and Taylor are credited as Executive Music Producers, while Macrae, Fredriksson and Shirley-Smith are credited as Queen Music Co-Producers.

Joshua J Macrae is full-time engineer at Roger Taylor's studio in Surrey.Macrae is Roger Taylor's regular engineer and manager of the drummer's The Priory Studio, while Shirley-Smith and Fredriksson are Brian May's engineers and run the guitarist's private Allerton Hill Studio — both studios are located in Surrey. The three engineers enjoy mixing and co-production credits on almost all recordings that Queen, Taylor and/or May have been involved in over the last few decades, including 14 tracks on Bohemian Rhapsody: The Original Soundtrack — the other eight are original album tracks. The soundtrack album itself has reached number one in many countries, and got to number three in the UK and the US, and it still remains in higher regions of the charts four months after its release.

Needle-drops & More

The involvement of Macrae, Fredriksson and Shirley-Smith began with a visit from movie sound supervisor John Warhurst. Macrae: "When John came down to see us, the movie-makers had in mind to re-record all the Queen songs that were to be used in the movie. I think John had done a number of films where there wasn't a positive connection with the musical artist involved, and where they did not have access to the masters, so they were fully prepared to go down the route of re-recording every note and vocal. In fact, they had already hired an arranger who had a good understanding of Queen's music, and were discussing who to hire to replay the guitar parts and so on. When John came in with the script, he asked: 'What do you have for us?', clearly not expecting much."

Justin Shirley-Smith is one of two staff engineers at Brian May's Allerton Hill Studio.Shirley-Smith: "Some of what they wanted were what they called 'needle-drops', which is simply the original studio recording being played in the movie. The other ones were live performances. For the needle-drops his first question was: 'Do you have the original multitrack masters?' The answer to that was yes, and better still, we also already had pre-mixed stems from some of these masters, because we had reverse-engineered these original mixes in the past for other projects. To his surprise and delight, we then told him that we also have the multitracks of many live recordings, which meant that they also didn't have to re-record these.

"The live recordings we have are of pretty good quality, which was important, because the movie-makers were very particular about the quality needed. The recordings we have, for example of Hammersmith Odeon and the Rainbow Theatre in the 1970s, are really beautiful. As we spoke, John became happier and happier, realising how much original Queen material could be used. He then asked us whether we could make stems of tracks where there weren't any, and again we said we could. The film-makers could not believe their luck!"

Moving Mountain

To understand how and why Shirley-Smith, Macrae and Fredriksson were so well prepared when Warhurst came knocking on their doors, we need to backtrack a little. One essential bit of background is the fact that the three have worked for Taylor and May for a long time. "I have been with Roger since 1987," explains Macrae, "I played drums in a band with him, the Cross, until 1991, and then started engineering for him. We moved to the premises where we are now in 2004. The studio is private, with occasional use by friends. In the old studio we had a 56-channel Amek Mozart desk, but we are fully in the box here."

Kris Fredriksson, Brian May's other staff engineer, at Allerton Hill."I used to play drums and still play guitar and a bit of piano," continues Fredriksson. "I studied music and engineering, and I began working for Brian in 2001, having worked at Mountain Studios in Montreux before that. There's so much going on within the Queen world that it's a full-time job for all three of us. We do archiving, there are projects like the Bohemian Rhapsody film, Brian put out a new song on New Year's Day ['New Horizons'], he does guest appearances with other artists, and there's the Queen catalogue to look after, which involves remastering, remixing, reissues and so on. It's several jobs into one, with no time for anything else. Mad but good!"

Allerton Studios is based around a Neve VR console."I had piano, violin and 'cello lessons as a child," adds Shirley-Smith, "and then played guitar in a band and wrote songs. I applied for some jobs at recording studios in London, but got a job at Queen's Mountain Studios, at age 18, in 1984. I have been part of the Queen family for a long time now! Mountain Studios was a commercial studio, so I engineered many other artists there as well. David Bowie, who lived close by, was always in and out, and Chris Rea worked there, as did AC/DC, and so on, and there often was stuff happening related to the Montreux Jazz Festival. Brian asked me to come to the UK in 1991, even before Freddie died, to finish his solo album [Back To The Light, 1992]. We had a tiny desk and two Sony 24-track machines, and a massive billiard table which was pushed into a corner. After that Brian got a 60-channel Neve VR desk, which is still there." Today, Mountain Studios is a museum dedicated to Queen, with one poignant feature being the room where Mercury laid down his last vocals, in May 1991, recorded by Shirley-Smith and David Richards.

For Posterity

As Fredriksson explains, the trio's long service means that they have a deep knowledge of Queen's recording history. "All three of us, along with Queen's archivist Greg Brooks, are involved in the tape libraries, which is separate from our job of running the studios. Sometimes we do transfers in one of the studios, sometimes in other facilities, while the vaults themselves are in lots of different locations, depending on the formats, and for obvious reasons — we don't want to run the risk of losing everything! The aim is to preserve every single Queen recording, but because there's so much, what we archive at any given time is always project-driven. Years ago, we started with the important stuff, the stereo quarter-inch masters of the albums, and copied them to other analogue formats, and then later we copied them to digital when we had that, and in 2002, when we got 192kHz, we also started copying the multitrack masters."

Allerton Hill Studio is home to one of the last Studer A827 machines ever made.Shirley-Smith: "The funny thing is that the older the technology, the more robust it is, so in archiving we also focused on what we call eradication projects, for example U-Matic and DASH recordings. These are the most vulnerable, and also, we were not sure for how much longer we would have machines to play these things on. Analogue tapes, and in particular two-inch tapes, are the most robust, although we do have to bake them. We have an incubator that fits 12 reels of two-inch. We bake analogue tapes as a matter of course, four days at 50 degrees C, and these tapes always play back without any problems on our Studer A827 24-track, which is one of the last ever made. I think it's called a Gold Edition."

Fredriksson: "The later Queen albums were recorded on two 24-tracks, so we're dealing with 48 tracks of audio. If you also copy all the out-take reels, you end up with a lot of material! Over the course of the '00s there was an initiative to create 5.1 mixes for every Queen song that has a promo video, and we also delivered Queen songs for several movies — for example, Blades Of Glory [2007] used the song 'Flash'. In all those cases we had to create digital stems of the songs, and this meant that we had to reverse-engineer the mixes. This involved first of all carefully going through everything to make sure that we used the correct takes and edits."

Shirley-Smith: "The guitar, and especially the vocals, might take up six or seven tracks, and sometimes the comps were done on the desk, so there wasn't a single track on the multitrack where you could say: 'This is the lead vocal comp.' In some of the cases where there was such a track, we would unpick it, creating the same comp again from earlier generations of tape, because on some songs they had been forced to bounce from one multitrack to another. So we'd go back one or two generations, and once we had the correct performances, re-comp them, and often also apply CEDAR audio restoration."

Matching Mixes

Reverse-engineering the mixes didn't only involve retracing the often very complex overdubbing and editing steps taken by Roy Thomas Baker — and other Queen producers such as Reinhold Mack and David Richards — before compiling everything in a tidy Pro Tools session and restoring the audio. Macrae, Fredriksson and Shirley-Smith also had to remix these sessions, making their new in-the-box mixes sound exactly the same as the original analogue mixes.

Fredriksson: "Queen obviously put a lot of time into writing the songs, and then they arranged and rehearsed them before they went into the studio, after which they would record and overdub in incredible detail. Finally, there was the mixing process, which was a whole other performance in itself! They were all hands-on on the desk, and used every single trick in the book, vari-speeding things and just generally messing around with things in the mix. If you compare the naked tracks on the multitrack to the final mixes there often is a phenomenal difference. Plus a lot of these mixes were done in sections and then edited together."

Shirley-Smith: "In approximating their mixes, we had to look at where the song was mixed, what board was used, what outboard they had used, and so on, and this would give us a good starting point. We have the original stereo mix in the session and we then A/B that against the mix we are doing. It's a very painstaking process to achieve exactly the same mix, and then to print that in stem format. With later sessions there would be recall notes, but in the '70s and early '80s people were not doing that, although there would sometimes be an occasional EQ knob drawing on the back of some track sheets to give a bit of a clue."

Macrae: "Welcome to our world! Occasionally we would ask Brian or Roger if they remembered what went on, but of course, we've worked with them for such a long time that some of us were there at the original mixes. Plus, after all these years we know what Roger and Brian like, so we don't go down cul de sacs. In approximating these mixes many of the UAD plug-ins were very helpful. They have great channel emulation plug-ins and things like that, and once you find the right emulations of the gear used at the time, you can home in on the sound you're after much quicker than if you are using just a random plug-in."

Shirley-Smith: "I hate having to do things twice, so we were very systematic. We played every tape we transferred to WAV from beginning to end, including any blank bits and tones, not just the part that we needed, and logged what we had in the database, so we never have to go back to the original tapes again. For the same reason, after we reverse-engineered a mix, we would also print stems. This also meant that we had stems for many tracks. These pre-mixed stems can be used for any movie project, and of course the makers of Bohemian Rhapsody were very happy with that. With this head start Paul Massey was then able to add his magic in the dubbing theatre."

Get The Band Back Together

'Reverse‑engineering' past studio and live recordings was only a part of Fredriksson, Shirley-Smith and Macrae's work on the Bohemian Rhapsody soundtrack. The trio also mixed Queen's famous Live Aid concert from scratch, and did some new recordings, notably the opener, '20th Century Fox Fanfare' (see box). Another three songs on the soundtrack also contain newly recorded elements: 'Doing All Right', 'Don't Stop Me Now' and 'We Will Rock You'.

The latter two are among Queen's greatest hits, but 'Doing All Right' was originally written and performed by the group Smile, whose members were May, Taylor and bassist/singer Tim Staffell. Fredriksson: "'Doing All Right' is pretty much a brand-new recording. There's a small section in the middle that comes from an unreleased recording from Smile from 1969 — they had a recording contract, with Mercury Records! They are seen performing that song in the movie, and they wanted to re-record the song, so we did a session with Tim in Abbey Road, where he sang and played the bass. All three members of the original band sing a verse, so they were back together after 50 years, which must be record-breaking."

Shirley-Smith: "On 'Don't Stop Me Now', when we did the remasters in 2011, we unearthed all the rough mixes and outtakes and found this rhythm guitar that had not been used for some reason. At the time we did a mix including that guitar, and then for the soundtrack album Brian overdubbed all the guitars from scratch the way he plays them today, which gives a whole different feeling to the song. The 'movie mix' of 'We Will Rock You' is steered by what happened in the movie. In the original script it starts off with Brian teaching them how to start the song, in the studio, and then it cuts to live performance. So that's how we did the song. But in the movie they then changed it: first there's the scene in the studio, then it cuts to live performance and then back to the studio. However, this would not make any sense if you listen only to the audio, so Roger and Brian decided to put the original edit on the soundtrack album."

History In The Making

On to the centrepiece of Bohemian Rhapsody: the band's legendary Live Aid concert. It is both the climax and the emotional resolution of the movie, and the most important segment of the soundtrack album, with four songs (out of a total of six performed). Queen's set left a huge impression on the audience at Wembley Stadium, despite the fact, remarks Fredriksson, that "Queen weren't on the original bill. They were added after the concert sold out, so it wasn't even a Queen crowd!"

The multitrack that shouldn't have existed: Queen's iconic Live Aid performance was captured on a single reel of 24-track two-inch tape.The concert has never before appeared on an album, but the original stereo mixes and footage were released as part of the Live Aid four-DVD set in 2004. Three years later, it appeared as a bonus feature on a special edition of the Queen Rock Montreal DVD, mixed by Shirley-Smith and Fredriksson from the original multitrack. For Bohemian Rhapsody, Shirley-Smith, Macrae, and Fredriksson decided to redo the entire mix. They could do so only courtesy of the courage and foresight of Jeff Griffin, BBC Radio 1 concert co-ordinator at Wembley Stadium in 1985, whose attitute was in stark contrast to the US crew, who deleted the recordings of the Philadelphia Live Aid concert.

Shirley-Smith: "Bob Geldof told Jeff that he was not allowed to multitrack record the concert, because some artists had said they would not appear if they were recorded. But Jeff told him, 'I'm sorry, this is such a historical event, I cannot not record this.' If it wasn't for Jeff, we would not have had a decent multitrack recording. However, you were never going to get a perfect recording in those circumstances, with just 24 tracks, and all these bands playing short sets, and having a very swift turnaround. They had designed a circular rotating stage divided in three, so each act could set up in their third of the circle, and then they literally just swivelled it. It was amazing, and an approach still used today. Although each band could use their own live setups, there were always going to be problems with the technical quality of the recordings.

"For example, there was a little distortion on Freddie's lead vocal. This was one of the reasons why the film team thought they might need a vocal double. They thought that they would need perfect sound to go with the high-definition pictures, and that the slight distortion on the vocals would not be good enough for a Hollywood movie. In fact, they did sessions in Abbey Road during which they recorded a singer mimicking every lead vocal track Freddie had done that they wanted to use in the movie. The reason for this was twofold: one was that they had to make the shifts believable between singing and spoken word, with Rami speaking, and for that it's much easier to work with the perfectly recorded, dry double vocals. Secondly, when you solo live vocals from any concert recording, they are not going to be pristine. The film crew commented on issues like, 'The snare drum is distorting in the vocals,' or 'There's a tiny crackle here.'

"In the end, the decision was made to work with the live recordings and improve them as much as possible. The only singing by the vocal double that was used are bits for which no recordings of Freddie exist, for example where he sings 'Happy Birthday' to himself at the piano. We are all very picky about technical quality, but you have to balance that against the emotional impact. You want the energy of the original performance. No-one will be sitting in the cinema thinking, 'Oh, my goodness, there's a tiny bit of distortion on the lead vocal.' You just go: 'This is exciting!' In fact, that little bit of distortion adds to the excitement. And also, that concert is so well-known, if you change anything in it, you're going to be nailed to the wall!"

The Live Aid concert scene in Bohemian Rhapsody is stunningly realistic, thanks to a combination of the original audio, state-of-the-art CGI, and the director, actors, choreographers, costume and set designers going all out to replicate even the tiniest detail from the 21-minute set. Fredriksson recalls: "I went along to see them rehearse early in the process, in some tiny old hall, where they were working with this amazing choreographer, learning every single move from the moment the band walked on stage, in real time. The attention to detail was phenomenal."

Tape To 'Tools

Shirley-Smith explains why the trio took the decision to mix from scratch and not to retrace their steps from 2007. "Kris and I had done stereo and 5.1 mixes at the time, on the Neve 88R desk in Sphere Studios in London. We felt we could do a better job today, because we're always developing new techniques. Because the 2007 mix was done on an analogue console, we could not really use that mix as a starting point. We had always had a copy in our archives, but starting again also gave us the opportunity to seek out the 24-track master in the BBC archives. We did our own transfer of the master, using Pro Tools HD IO. As it happened, there was very little difference between the two."

Macrae: "We actually loaded the entire master tape transfer into the Pro Tools session for the 2007 Live Aid mix, and deleted all the automation, with the exception of some EQs on the toms and overheads to take out some guitar feedback, some fader moves on the toms group, and on the aux tracks that each backing vocal has, just bringing up those parts where needed. This was an unusual situation, because I normally lay out each session manually from scratch. We don't use a template. Despite it being the same band, no performances are the same, and it doesn't take long to set things up. Even a vocal plug-in chain takes just a few clicks. We listen, and decide what the session needs. Sometimes you find so much vocal reverb in a hall that you don't need any."

Fredriksson: "We always load entire concerts into one Pro Tools session, and have done so since 2002, when we started putting out a lot of live concerts. A two-inch multitrack is 17 minutes at 30ips, but in this case they had run it at 15ips, so the one reel could contain the entire performance. In other cases they daisy-chained two machines. Because we always bring all the material into one session, and then consolidate that, all files end up as long as the entire concert. The session becomes like a very long analogue tape that could not exist in reality. There sometimes are significant overlaps on these live concert tapes when they used two machines; in those cases we listen through and work out which tape sounds better and use that."

No Fixes

CEDAR Audio's Retouch was used to remove problematic noises from several of the Live Aid tape tracks.While mixing the Live Aid concert, the trio were at pains to avoid getting nailed to the above-mentioned wall. "It was all about getting it to sound powerful," comments Macrae, "and keeping the ambience — it is a rock band playing in a stadium! The main thing was keeping it real and not over-processing things, and not changing any of the audio content, so there were no edits, no fixing anything the band played, and there was no tuning. The only things we fixed were technical issues, like feedback squeal. The classic moment is when Brian's guitar amp had a tube failure in 'Crazy Little Thing Called Love', resulting in a horrible whistle that doesn't have a fixed frequency, making it difficult to EQ it out. Instead, we used CEDAR Audio [processors] to get rid of that. In the 'Ay-Oh' section, with Freddie singing back and forth with the crowd, one of the roadies is tuning the bass guitar, and this sounded on the PA. Because you really want to hear just Freddie and the crowd, we did our best to remove the tuning noises as much as possible. But because this concert is so iconic, we could not fiddle with it. Any iffy notes were left! It has become known as the best live performance ever, so we also didn't want to fizz it up and give it a modern feel. It had to remain authentic and raw."

The only thing that could arguably be called 'fizzing it up' was a way of enhancing the ambience that ticked all Queen's boxes in its grandiosity. Shirley-Smith: "Paul Massey wanted more of the ambience of a band playing in a stadium. With many live recordings, they try to dry things up and lose the ambience. By contrast, we always try to keep the ambience, because it is the vibe, and we certainly did this when we mixed the Live Aid concert. But Paul wanted even more ambience. The film guys were even talking about hiring a venue just to put a PA in there and play the music back in it! But at one point Queen + Adam Lambert were playing the O2 Arena in London, and were being filmed, so we had already arranged for extensive extra room mics to be put up in the hall. We went back to the Pro Tools sessions, printed new stems without our reverbs and delays, and played those through the PA at the O2 Arena, without the audience present, and recorded the room."

Fredriksson: "We used stems because you might want to adjust that mix in the room. You never know how it's going to sound. In fact, all the live music in the movie was played through that PA, and the ambience recorded. But we did not use any of that on the soundtrack album. The other thing that happened was that in 'We Will Rock You', the beat the audience in the movie is asked to do is stomp-stomp-clap. But for some reason, every audience in the world always goes clap-clap-nothing. Nobody had a clean recording of a huge crowd going stomp-stomp-clap. So Brian offered to get the O2 Arena audience to do this during the quiet moment in the set, when it's just him talking to the audience. That's how we got a recording of 20,000 people doing stomp-stomp-clap!"

The Ultimate Live Recording?

The Pro Tools mix session for Queen's Live Aid concert, complete with two-minute introduction by Mel Smith and Griff Rhys Jones, is exceptionally well organised. It consists of a total of 90 tracks, divided in six sections: original multitrack print tracks, 15 instrument group aux tracks, three master tracks, 15 aux stem buses, 17 stem print tracks, and 12 aux effect tracks. The multitrack print tracks in turn break down into a total of 22 audio tracks: two audience tracks, two toms with electronic drums tracks, two overheads tracks, hi-hat, kick, snare, bass, two synth tracks, piano, acoustic guitar, two electric guitar tracks, a track for Mercury's vocal mic when he was at the piano, a track for his handheld mic, and backing vocal tracks for May, Taylor, Deacon and Spike Edney, who also played keyboards. These audio tracks are sent to the associated aux group tracks below them: kick, snare, kit, bass, guitar, acoustic guitar, keys 1, keys 2, piano, four backing vocal groups, lead vocals and audience.

The entire Live Aid set was mixed from a single Pro Tools session. At the top are the original audio files transferred from the tape multitrack; the lower half of the session contains stems re-recorded into Pro Tools. [See righthand sidebar for downloadable ZIP file of a hi-res screenshot.]

If the session had been purely for audio, this would have been it, but because Macrae, Fredriksson and Shirley-Smith also had to provide stems for the movie, they routed these 15 instrument group tracks to 15 corresponding stem bus tracks below the master track, and printed these on 17 stem audio tracks below that. Underneath these audio print tracks, at the bottom of the session, are 12 aux effect tracks, with the usual assortment of reverbs and delays. One of these is called 'Splinge', and is a particular delay effect beloved by the Queen members.

The multiple reverbs in the Live Aid mix came from Avid's D-Verb and from the Lexicon 480.The three engineers used Brainworx's bx_console plug-in across all the original audio tracks. "The bx_console is a Neve emulation channel strip," Macrae explains, "which we used for EQ and compression, just like you'd do with a normal desk channel. It helps glue everything together. The kick also has the Softube Summit Audio TLA-100A [compressor], to keep it in place and beef it up a bit, and a send to the 'KikCho' aux effect track, which adds some [Avid] D-Verb reverb, with a medium non-linear reverb.

Lexicon 480 plug-in."The snare, after the bx_console plug-in, also has the Softube Summit Audio Grand Channel, adding EQ, compression and saturation, and a send to the 'Snare Echo' audio track, which has another D-Verb, with a small non-linear reverb, plus it has a send to another snare reverb aux, with the Lexicon 480. The bass and the piano both have the UAD 1176 A [compressor], and the piano a send to 'Piano Verb', which again has a Lexicon 480.

The 'secret sauce' in Brian May's guitar sound: a pseudo-random echo patch created using Waves' SuperTap."Both electric guitar tracks have sends to the 'Splinge' aux, which has the Waves SuperTap Delay, set to a kind of random arrangement, to give the feeling of the sound knocking about in an auditorium. Brian generally doesn't like reverb on his guitar, and prefers delays.

"After the bx_console plug-in, once again, both vocal mics have the UAD 1176, set to a high ratio, and the fastest attack and fastest release, catching the really loud, hard transients. Third in the chain is a UAD LA‑2A, which is a softer and slower compressor, and more for general level and sound. After that there's the UAD Neve 1081 EQ for some crispiness, and the last plug-in on the inserts is the Tokyo Dawn Labs Nova, which is a frequency-conscious compressor that takes out the occasional nastiness, frequency specific. It acts here like a de-esser. Both vocal tracks also have sends to the 'LV P N Hall' aux, which has the Lexicon LX480, set to 'Medium Hall + Stage', and the 'LV TDL' aux, which has the Waves H-Delay."

As well as reverb from a Lexicon 480, Freddie Mercury's live vocals were also treated with a ping-pong delay.The instrument group tracks have no plug-ins on them, other than the Softube Transient Shaper on the 'Snare Group' and the Waves REQ6 on the 'Guitar Group', and some treatments on the 'Audience Group' from the Avid EQ3 1‑band and the TDR Nova. For the stereo mix, the instrument group tracks were sent to the 'Sum=M=' aux, which has a UAD Massenburg Designworks EQ and the Avid Impact compressor.

"All the volume automation for the audio is happening on the instrument group tracks." Shirley-Smith clarifies.

"Only corrective volume changes, for example dipping an 's' or a pop, or changes in volume to correct the fact that someone adjusted the mic amp halfway through, are done on the audio track itself," Fredriksson adds. "If you don't do that, these things will drive the compressors the wrong way. The Massenburg pulls out the PAL line frequency, which is a whine inherent in the PAL television format, at 15.625kHz. You get this ringing and it drives me absolutely mad, so we have to notch that out. The Impact is the bus compressor."

While mixing they listen to Genelec loudspeakers: 8260A SAM with 7271A SAM sub at May's studio and 8250A SAMs with 7270A sub at The Priory. Shirley-Smith: "We also have a pair of NS10s, and listen to computer speakers, headphones, car stereos, mono radio and so on. You have to also hear things in real-world situations. I will listen to things focused in the studio, and then also unfocused, while doing something else with the track playing in the background. If it plays in another room it works even better."

The Masters

The final stage, at least as far as the soundtrack album went, was mastering. Fredriksson: "We have been working with Bob Ludwig at Gateway Mastering for about 15 years now. We spent a year remastering the entire catalogue in 2011, just dealing with the stereo masters when the band moved to Universal Records. That work was done very meticulously, with us digging through archives all around the world finding tapes to make sure we had the best possible sources. All that was mastered by Bob, and these are the album tracks that appear on the soundtrack album. The newly mixed material was mastered by Adam Ayan, also at Gateway, and this blended in well."

The work of Macrae, Shirley-Smih and Fredriksson was only part of a huge team effort on the audio front. Most of that team are shown in this group photo taken at Twickenham Studios: from left, William Miller, Tom Melling, Kris Fredriksson, Joshua J Macrae, Nina Hartstone, Paul Massey, Miranda Jones, Brian May, John Warhurst, Tim Cavagin, Louise Burton, Alistair Hawkins and Justin Shirley-Smith.