Kevin 'Caveman' Shirley

Kevin Shirley photographed in New York's Hit Factory.

When Jimmy Page decided to mine a massive archive of decaying Led Zeppelin live footage for a DVD and double CD, the epic task of restoring, editing and mixing the audio went to rock specialist Kevin Shirley — who has gone on to help veteran metallers Iron Maiden return to the upper reaches of the charts.

It is widely believed that cavemen had long hair, carried big sticks, were driven by instinct, liked to whack each other, and were not usually called Shirley. It is also commonly assumed that cavemen died out a long time ago, so it's a little surprising to find a specimen currently alive in New York. This particular long-haired caveman is known for whacking others in the stomach with the pure, unadulterated, volume-to-11 sound of heavy metal and grunge. His big stick is a custom-built $100,000 Pro Tools system, which reaches the parts that his beloved analogue can't quite reach. Oh, and, er, his name is Shirley.

'Caveman' is the nickname of Kevin Shirley, producer, engineer and mixer extraordinaire, whose main ambition in his professional life is encapsulated by the title of an album by a relatively unknown US band called Healing Sixes (featuring drummer Jason Bonham, the son of the deceased Led Zeppelin drummer.) The producer sank $200,000 of his own money into the Healing Sixes's debut album, which is called, entirely appropriately, Enormosound. It was released last year to spectacular indifference from the record-buying public, which is a pity, since Enormosound is actually rather good.

Shirley has described himself as a "big, hulking Neanderthal with long hair," which apparently explains his 'Caveman' moniker. Since he escaped his native South Africa in 1986 he has been involved with some very successful artists and bands. These include the Black Crowes, Aerosmith, Silverchair, Joe Satriani, Dream Theater, Journey, Rush, Bon Jovi, Iron Maiden and, for some reason, Olivia Newton-John (for more details see Shirley's comprehensive web site at www.cavemanproductions.com).

Winning The West

Kevin Shirley is already well known in his field, but his status can only improve this year thanks to his involvement with two high-profile projects. First and foremost, he spent more than half a year with Jimmy Page engineering and mixing the music for the already legendary live Led Zeppelin DVD, as well as Zep's three-CD live album How The West Was Won. In addition, Shirley produced, engineered, and mixed the latest instalment of the Iron Maiden saga, Dance Of Death, which is expected to have reached the top of the hit parade by the time you read this.

The Led Zeppelin DVD has been called "the rock music equivalent of the Holy Grail" and was accompanied by considerable press, much of it focussing on the stunning quality of the visuals and the work of producers and DVD Creative Directors Jimmy Page and Dick Carruthers. One of the DVD's accompanying booklets tells how Page and Carruthers began with 132 cans of film negatives and two sets of two-inch videotape. The latter had to be baked in an oven, and the search for an operational playback machine for the now obsolete two-inch video medium led all the way to Singapore. Carruthers, who has also worked with the Rolling Stones and Oasis, stated that creating the visuals was "like building a cathedral from matchsticks" and the booklet mentions how bleeding colours, shaking lines, and worn-out video tape were all restored in state-of-the-art digital workstations.

DVD Creative Director Dick Carruthers described creating the Led Zep DVD visuals as "like building a cathedral from matchsticks".Very impressive indeed, but what about raison d'être of the whole thing, the music? While Page and Carruthers were lauded for their considerable achievements, our New York 'Caveman' was more or less forgotten. This is a great pity, since the sound on both the DVD and How The West Was Won is astonishingly bright, explosive and consistent, despite coming from several different recording media and live shows and spanning a period of nine years. What's more, the story of how Shirley managed to upgrade cranky 30-year old recordings to his trademark 'enormo-sound' turns out to contain as many interesting twists and turns as that of the visual restoration.

Utterly Irresponsible

Shirley's involvement with Led Zeppelin and Jimmy Page goes back to the latter's collaboration with the Black Crowes. In 1999 and 2000, Page and the Black Crowes toured together, playing a mixture of rock & roll standards and Black Crowes and Led Zeppelin material. Shirley had produced, engineered and mixed the Crowes' album By Your Side (1999), and did the same for the million-selling live recording of Jimmy Page & the Black Crowes called Live At The Greek (2000). In April 2002 Jimmy Page invited the Caveman for a meeting in London. "Jimmy wanted to know how I dealt with new technologies," Shirley recalls, "like surround sound and digital, and asked if I was interested in helping him with some live material that he wanted to put together from archive and bootleg footage."

Being a long-standing Led Zeppelin fan, Shirley was very excited about the prospect. He had some premonitions about the technical challenges such a project would pose, and with his commission as yet unconfirmed, Caveman jumped the gun, and laid out $100,000 on a brand new, enhanced Pro Tools HD system, much to the "disgust" of his business manager — who, understandably, thought this was utterly irresponsible. "I took a big chance and trusted my gut instinct," recalls Shirley. "And I knew that at that time there were no systems in the world that could do what I wanted to do. I wanted huge capacity, great quality, and 100 percent reliability. I've worked with rental systems and they always have problems. I didn't want any crashes or noises from radios or cellphones. So a guy in upstate New York, Vincent Gutman of Märc Systems Inc, built a Pro Tools rig for me that is unbelievably stable. He'd also built my previous rig and since 1998, when I began using Pro Tools, I've never had a single crash. Everything is gold-tipped and stripped up and with super-quiet fans and the best cabling, unbelievable. He does a great job earthing and isolating the whole system. The new rig was fantastic, the best in the world, and perfect for this project."

Shake & Bake

Presumably to the relief of his business manager, Shirley did get his commission, and he had the Pro Tools system shipped over to London in May 2002, when work began on the Led Zeppelin project. Neither he nor Page had anticipated the scope of the task ahead of them. Work at Sarm West studios was anticipated to last 10 weeks, but eventually took six months, ending in late October 2002. With the recordings of the Iron Maiden album starting not long afterwards, it meant that Shirley spent almost a year in London, a city he didn't enjoy much. (Compared to New York, he found London less friendly, its traffic worse, and "Pubs close at 11pm. What's that about?")

The plethora of recording formats he was confronted with, and their often advanced state of decay, meant that things were anything but easy-going. "The material from the Royal Albert Hall show [1970] was recorded on eight-track one-inch tape," Shirley elaborates. "There were the two Californian shows [from 1972] that ended up on How The West Was Won, three Madison Square Garden shows [1973] and five Earls Court shows [1975]. These were all recorded on 16-track two-inch tape. Finally there were two Knebworth shows [1979] on 24-track two-inch tape." (Shirley did not work on the 'Extras' on the DVD, which contain mono soundtracks that came with the images.)

"We had to bake all these tapes in an oven because some of them had moisture in them," Shirley continues, "which turns the glue that bonds the oxide to the tape into a sort of jelly. When you play a tape like that back, the oxide will scrape off and stick to the tape head. So you can destroy the tape just by playing it. Through baking at about 55C you get the moisture out and the tapes are playable again, at least for a while. The first playback is usually the most stable. But it takes about 60 hours to bake each tape, so immediately we were weeks behind while we waited for the tapes to be baked."

Once the tapes were well done, special heads and tape machines had to be found to play back the older eight- and 16-track formats, and deal with any kind of what Shirley calls "funky noise reduction. In the same song, some tracks wouldn't have noise reduction, while others did. For instance, there was never any noise reduction on the hi-hat and kick drum, but it would be on other things. There also weren't any track sheets. Most of the time I was guessing what was on what track and how it was recorded."

1000 Gigabytes

Shirley eventually loaded all the material from the multitrack tapes into his Pro Tools HD system at 24-bit, 96kHz, using the system's own converters, making sure that he captured that precious first pass of the tape past the heads in one go. "We didn't bother going to a 192kHz sampling rate," explained Shirley, "because some of these shows were three hours long. Even at 96kHz we had stacks and stacks of hard drives floating around. We had 13 shows, meaning about 45 hours of multitracked music. I think in the end we used about 14 72GB drives, so a total of about 1000 Gigabytes."

After the multitrack material was safely transferred into Pro Tools, Shirley made rough stereo mixes of everything, and he and Page spent hours listening and making "copious notes. He knew more about which performances he liked, and I made notes about what was pertinent to my job, ie. more technical issues. But I think since I'm a producer as well, I was a good foil for Jimmy. He used me to bounce things off."

Given the state in which they had found the tapes, Page and Shirley were delighted by the actual sonic quality of the recordings. 'Caveman' reckons they are testimony to the currently disappearing art of engineering. "The recordings were really, really good. One of the things this highlighted for me was how, with the advent of cheap digital recording gear, engineering skills are getting lost. People can make records in their living rooms and think that anything will do, because a couple of such bedroom records make it and sell millions. But they don't know how to make good organic recordings of real instruments.

"The Royal Albert Show from 1970 was recorded on seven tracks of an eight-track tape: vocals, guitar, bass, three drum tracks, plus one audience track. The drum tracks consisted of two overheads and one kick drum, and sounded great. I'm tipping my hat to the recording engineers of the early days, because they really had to get the balance between the drum microphones right. As a result the recordings ended up sounding better than those in later days, when they just put a mic in front of each single drum. It made it easier from their point of view, but it was a lot more work for me to get a good sound.

"Whoever recorded the Royal Albert Hall show got a good balance, but there were a couple of songs where I had to use some tricks to bring the snare drum or toms out. I'm talking about using EQ or compression to highlight things. For instance, I would use a Fatso compressor that helped me isolate frequencies in the snare drum and smash it up a bit so it sounded a bit louder. I also used a gate to trigger an EQ, so that when something popped up on the snare drum, you'd get more bottom end into it. I also remember how John Paul Jones came into the studio and asked for some more definition on the bass. But I showed him how there was so much leakage from the bass on the drum tracks that there were times I had to take the entire bass track out. He got to see how complicated it was."

Compiling The Show

Jimmy Page had made the decision to make the DVD a 'best of' compilation of live material. Rather than showing several live performances in their entirety and having five different versions of 'Stairway To Heaven', 'Kashmir' and so on, he preferred to select the best versions of songs from certain locations and weave these into something that resembled a continuous concert. Only the Royal Albert Hall material all came from one show.

Page and Plant strut their stuff in stills from the Led Zeppelin live DVD.

"We did the Royal Albert Hall material first," recalls Shirley. "It was obvious that this was a great show from a great period in the band's history. Even as we were mixing the music they were still digging up footage from all sorts of places. The visuals were recorded on a variety of formats, and there were cameras that ran out of film, so we couldn't use a couple of songs, like 'Heartbreaker', because there was no footage at all. As you can see on the DVD, in some songs they had to use stills to cover missing footage. They took a lot of care in matching the video to the audio, sometimes working frame by frame."

Clearly, modern digital technology also proved essential in matching visuals to audio, a process which was Dick Carruthers' domain and in which Shirley took no part. The same went for the speed and ease offered by direct access — imagine having to trawl through, and compare sections of, 45 hours of tape! Having restored the Albert Hall material, Caveman moved on the three Madison Square Garden gigs in 1973, which also formed the basis for the only previously existing official Led Zeppelin live album and video, The Song Remains The Same. It has a reputation for being lacklustre and below par, but Shirley does not agree.

"I think it's a very good record with great mixes by Eddie Kramer. But hopefully what we did is a step up from that. Obviously Jimmy didn't want to go over the same material again, even though the band played them so differently every night. There also were songs we had already covered from Knebworth and Earls Court. We were trying to find a cross-section of the band over the whole period, and we ended up with five and a half hours of material, including a magical acoustic section and phenomenal performances of tracks like 'In My Time Of Dying', 'Stairway To Heaven', 'Achilles' Last Stand', and 'Nobody's Fault But Mine'."

Power And Thunder

"It was Jimmy's project," emphasises Shirley, "so what to include and not to include was his call. I think Jimmy wanted a historical overview, but the DVD and CD are also art and an entertainment package of the greatest rock & roll band ever, so we had to do a few small repairs. For instance, it would be a pity if, in the middle of a great guitar solo, a missing bass note destroyed the floor of the song. So, if the correct note was played elsewhere in the song, we could just copy it across. There was one song where Bonzo hit his huge gong but there was no microphone on the gong, so you heard almost nothing. So we found the sound of the gong somewhere else on the tapes and flew it in. These are the kind of things Pro Tools is great for.

"Another example of using Pro Tools was that I'd make a digital copy of the vocal track, and clean it up so the copy didn't have all the extraneous noises and stage leakage in it. I'd then compress the copy, and combine both the cleaned-up vocal track and the original unedited version of the vocal — I wanted the power from the compressed, cleaned version, but there's a lot of important information in the uncleaned mic. Then, on 'Stairway To Heaven' at Earl's Court, the stage lights were down very low and this caused a lot of ground hum on the guitar amplifier. There was a terrible buzz that almost made the guitar unusable. So I found a plug-in called DNR, a digital noise reduction program, fed it a sample of the hum I wanted it to remove, and then put audio in for it to treat. It worked, but it was very slow and tedious, because I had to scrub every single note individually."

Shirley uses plug-ins very rarely, because he hasn't found much use for them and generally speaking doesn't like the sound. So it comes as no surprise that he opted to mix the Led Zeppelin material through an external desk, in this case the J-series SSL at Sarm West. "I don't like to mix in Pro Tools," says Shirley, "because I like using analogue desks and outboard equipment. I just think it sounds better, and you can manipulate the audio more easily. People who work on popular music in the digital domain with samples and stuff won't necessarily need the flexibility to manipulate sound on an analogue desk. And certainly I don't need a massive amount of fader movements and panning backwards and forwards from a digital desk, because rock doesn't really call for that a great deal. I do very occasionally use the Pro Tools digital desk for special effects in mixing, because it seems these days everyone wants their stuff to sound like a video game. But I haven't heard a digital desk that I like the sound of yet. I always find there's more air in the sound with analogue desks.

"That air is important when you're dealing with, for instance, something like the drum kit of John Bonham, who was not only the best drummer in the world, but also has the most distinctive sound of any drummer in rock & roll. Not all of the recordings were flattering to the drums, and the sound also varied from show to show. They're live shows and sometimes a random mic was stuck on them, and so on. So in the mix process there had to be a bit of manipulation, moulding of the sound, especially of the kick drum. I had to do quite a bit to get all the definition and power and thunder out of the kick drum, using a variety of compressors, and desk and outboard equalisers. Jimmy had told me at the beginning of the project that he wanted to hear a lot of cymbals on the drums. So I bussed all the drums through two channels and put a pair of brilliant old Fairchild compressors across the whole kit. This gave it that slightly compressed Led Zeppelin sound."

Essence Of Zep

"The key to all the mixes was to have a sense of continuity, from outdoor shows to indoor shows from any period. The other thing was to instil the essence of Led Zeppelin. I would go back and listen to their studio recordings, not to copy them, but to make sure the spirit of the sound is there, and then to enhance the sonics and the interaction between the instruments. For instance, on 'Kashmir', on the studio recording, there is that signature sound of the delay on the kick drum, so on the Knebworth performance on the DVD, I added the delay to the kick, which may not have necessarily been the way it sounded live, but it certainly enhanced the emotion of the original recording. I only used effects for these reasons. There was another situation in the Earls Court shows where we couldn't use the audience microphones for ambience, so I'd try to recreate a digital reverberation setting that was similar to the acoustics at Earls Court. One way in which the balance differed from 30 years ago was to have more bass, and a little more brightness in the overall sonics. Records do sound a little different now, and we're used to hearing more bass. I tried to make the music sound as rich and full as records sound now, but still maintaining the warmth that we associate with Led Zeppelin.

"On Robert's voice I used the new reissue LA 1176 compressor, which sounded fantastic. I also stuck a de-esser across it, because some of the live mics are very sibilant in the top end to make them clearer in the live environment. If the proximity effect ever was an issue, then this compressed second track I'd copied and cleaned up in Pro Tools made a big difference in smoothing things out. The unedited vocal track is unprocessed. On both the bass guitar and the bass pedal, I used a vintage 1176 compressor, and on the keyboards I resorted to all sorts of trickery. On 'In The Evening' I needed to enhance a single, small mono keyboard signal so that it could drive the song along, so I squeezed it, fattened it up with an analogue patch on the Eventide H3000, and faked up the stereo with a slight delay and pitch adjustment. I think it sounds huge now!"

On Jimmy Page's guitar Shirley used a Peavey Kosmos Pro, a rackmounted processor that adds definition and energy to low frequencies. "Sometimes the recording of the guitar had a kind of nasal twang, and the Peavey helped, giving the guitar a real thump on the bottom. It gave the feeling of being much closer to the amp than just from that nasal effect. When you stand in front of a guitar cabinet you get this thump in the bottom end that you can feel in your belly. The Peavey helped me recreate that. I had just a little Aural Exciter on the acoustic guitar to bring out the sparkle, and a little valve compression."

Burps & Farts

According to Shirley, there were small but significant differences between the stereo mixes for the How The West Was Won, recorded in two shows in Los Angeles, and the stereo for the DVD. "For the Los Angeles and Long Beach shows I tried to enhance the stereo imagery for the guitar," explains 'Caveman', "so that it would sound fuller. For instance, I programmed panning in Pro Tools on the electric guitar in 'Dazed And Confused', to make it more interesting. On the CD, I didn't want the risk of it sounding like early Van Halen, with the guitar on one side and you lose it on the other side. I wanted it to sound a bit more cohesive. Because the music for the DVD is sync'ed to images, I wanted the position of the guitar to be very clear. Jimmy was always on stage left, for the audience on the right, so his guitar is predominantly in that location.

"I first mixed the whole DVD project in stereo and then set up the desk for 5.1 and mixed everything again. After this I mixed the stereo for How The West Was Won and then I did the 5.1 mix for that [which will be released in the DVD-Audio format on November 6th]. The most convenient medium to mix to was Pro Tools, via the 192 converters, because we had to synchronise stereo and 5.1; we needed eight tracks to record to. I did actually run some stereo mixes to my Ampex ATR102 two-track, but at the end of the day I was happy with the sound of the digital converters.

"I had the same architecture for all the 5.1 mixes on the DVD, which is that it is mixed from the perspective of sitting in row six or seven in the middle in the audience. So I put the drums a little further back and brought the vocals forward, Jimmy on the right, and bass in the middle. On 'What Is And What Should Never Be' it's part of the guitar orchestration for it to move around in the break section, while in the guitar break of 'Dazed And Confused', I wanted to capture the whole ethereal atmosphere of the violin bow section. I thought moving that around in the 5.1 sound field made it exciting. Also, I put the audience microphones in the rear and the uncompressed, untreated vocal mic in the central front speaker. I thought all that stuff, all the hiccups and coughs, burps and farts and him moving backwards and forwards around the instruments is fascinating to listen to. If anyone is interested in that, all they have to do is isolate the centre channel. That's about the most honest thing you'll ever hear."

Balancing Ideas

Compared to the trickery that goes into live albums and DVDs these days, 'honest' is an appropriate adjective for How The West Was Won and the Led Zeppelin DVD, even if it's an enhanced honesty, resulting in caveman-calibre 'enormo-sound.' As indicated above, Kevin Shirley has also used his talents to good effect with other famous artists, and notably British heavy rockers Iron Maiden. Shirley has been involved with them as engineer, producer, and mixer since 2000's Brave New World, and the live double CD Rock In Rio (2002). Now there's Dance Of Death, co-produced by Shirley and the band's bassist, Steve Harris, and recorded from January to April of this year, again at Sarm West.

Sarm's SSL desk throughly marked up for the Iron Maiden recordings."For me, being producer, engineer and mixer are three very different jobs with different requirements," says Shirley on the nature of his work. "I think given the quality of great microphones, engineering is overrated. Certainly there are great engineers, guys who set benchmarks that have rarely been bettered. I don't see myself as one of the great engineers, I think I'm more of a workman engineer, being able to get an adequate to good sound from organic instruments. For me the basic art of engineering is about getting a good sound at source, and then I won't fiddle with it too much during the recording process. Once I'm satisfied that I have a good basic setup, I work on getting the performances of the artist and working on song structures and arrangements. I'm not the kind of producer who puts his own stamp on the music. I'm there to help a band create its own voice. With Iron Maiden, they know what they want. I was there to help them get their vision across. Sometimes I acted as a buffer, I was editing and balancing conflicting ideas."

In the case of Brave New World, helping Iron Maiden get their vision across meant that Shirley made a suggestion which took the band by surprise. "One of the things I really like to do is capture a band playing live in the studio," discloses Shirley. "I suggested to them that they record Brave New World like that, and they were sceptical in the beginning, because they had always worked through overdubbing. But they ended up loving it, and we recorded Dance Of Death the same way. You get things very quickly this way and you get a real sense of whether things are happening. One of the things that's quite unique about Iron Maiden is the push-pull between the different musicians. Steve Harris really pulls the band along with his bass guitar, he's always a little ahead of the drums. You could go into the computer and put him right on the beat, but then you get a totally different feel that's not Iron Maiden. By recording them live I could really capture their sound."

Left to right: Adrian Smith (guitar), Bruce Dickinson (centre) and Steve Harris (bass) rehearsing during the Dance Of Death sessions.

Instinct

To make sure he had enough separation for later manipulation, Shirley placed the drums and Steve Harris in the main studio room, with the bass cabinet isolated. Guitarists Dave Murray and Janick Gers were in a separate room, guitarist Adrian Smith in yet another room, and singer Bruce Dickinson was in an isolation booth. "Everybody could see everybody else while they were playing. Another important thing was that the guitarists had their amps with them. That's something I've been doing since before I worked with Rush. The sound of the amplifier going back into the guitar makes the wood sing. It's a different tone than when you have the cabinet in another room."

Kevin Shirley at Sarm West during the making of Iron Maiden's Dance Of Death.Shirley used the same tools to mix Iron Maiden as for the Led Zeppelin material: Sarm West's J-series SSL desk, with Pro Tools used as a master recorder, though he also mixed to his beloved Ampex ATR102. "But Steve [Harris] preferred the sound of the digital. Steve also really steered me with the mixes. I first started mixing Dance Of Death like a modern rock record, very loud with a lot of compression. I've mixed a lot of modern rock, bands like Soil and Span and so on, and it's what record companies ask for these days. My Iron Maiden mixes sounded pretty good, but Steve came up to me and said, 'I think that your original rough mixes, without too much finessing and trying to get everything right, sounded cooler.' So I said 'Fine,' and mixed the way I did the rough mixes. I just pushed the faders up. It's very simple, very straight, not gimmicky at all. It's the way the band plays, and they love the record."

In response to the slightly incredulous noises made from the other end of the telephone ("Surely there must be more to a mix than that?"), Shirley adds, "I didn't add any reverb, other than perhaps some on the orchestra on two songs. Instead I used the room mics, and fitting the pieces together was mainly done with panning rather than EQ. What I do is really an instinctual thing. I don't have any plans, I just do it. For instance, after I've finished a mix, I don't check it on other systems or in the car. If you listen to things over and over again you suddenly go, 'Oh, that hi-hat bothers me,' or 'The bottom end doesn't sound quite right.' Instead I trust my ears and my KRK 6000 monitors — of which I have six pairs. If I have a good feeling about it in the studio, I let it go. I reckon that there must be some reason why the mix makes me feel good. And then I banish it from my memory. It's instinct that drives me."

Spoken like a true caveman...