Some of you may have heard of the Sgt. Pepper multi-track masters that recently surfaced. These contain various mixes from the Pepper sessions, as well as backing tracks, and full remixes of 5 songs from the album. I'm going to be uploading these to the bootleg forum soon as part of the Purple Chick Deluxe series.
For those interested in the technical side of things here is an explanation of the EMI mastering process, and information about the 'new' tapes by Jeff Westerman, via Terry Ott's blog. It is long, be warned!
Somewhere at Abbey Road there are miles of shelves, and on those miles of shelves are many many boxes which hold the "Master" tapes made by the Beatles.
The width of these tapes is 1", which is the most generous distribution of signal to media ever; meaning that each of the four tracks is allocated 1/4" of the tape width. This is good. The tape machine runs at 15 inches per second (ips), which was state-of-the-art at the time, and is still the favored mastering speed of many engineers. Tape can run as slowly as 1 7/8 inches per second past the heads, or 33/4 ips, or 7 1/2 ips or 30 ips.
The higher the tape speed, the better the resolution the sound has. Abbey Road recorded at 15 ips and mixed at 15 ips, sometimes at 7 1/2 ips. They also were geniuses at squeezing more sound out of or onto tape than almost anybody, so they could use different speeds almost as sound effects. In their hands, a slower speed might sound grittier, but just as musical. And the Beatles always enjoyed pushing the parameters.
Each Studer J37 4-track machine recorded each little track on 1/4" of the passing 1" tape. Upon playback, the output signal of each discrete track was fed to a separate input on the mixing desk. Each track was represented on this desk by a fader and some knobs in a vertical strip. Each track was playable to its given volume by how loud the fader was set.
Each fader strip also had a "pan" knob, which could be turned (picture a clock-face) in an arc between 7 o'clock on the left and 5 o'clock on the right. At 12 o'clock, the sound appeared to the listener's ear to be coming from the middle, when it actually came from each extreme side equally, creating the illusion of a "center." When the knob was turned to the 7 o'clock spot, the sound appeared to come only from the left of the spectrum, and at 5 o'clock, only from the right.
When multiple sounds were combined upon playback from discrete tracks, they could therefore each be placed at any chosen point in the left-to-right stereo spectrum. Greater separation was achievable with such panning.
A typical Beatles recording of the day would have the drums all recorded onto Track One, with lead guitar(s) and maybe a percussion part on Track 2, the bass onto Track 3, and the lead vocal and other solo and incidental sounds on Track 4. The drums on Track One would be set at 12 o'clock in the mix to give the song its center of gravity.
The lead guitar on Trk 2 would be slightly to one side, at 9 or 3 o'clock so it would stand out of the mix without having to be played too loud. The bass part would usually be mixed into the 12 o'clock position also, because it was a critical aspect of that center of gravity, too.
The lead vocal part would be mixed maybe at 1 or 2 o'clock in the mix, centering it but keeping it occupying its own space by having it slightly to the side. Sideways enough to make it very clear and commanding, but not tilted so far as to make the whole mix feel like it was "tilting" towards the right side.
The point of all this is that mixes are infinitely variable. Many engineers played with hard-panning, i.e., as on the early Beatles' American albums, where the band would be coming out hard on one side or the other, and the vocals would be all disembodied but crystal clear coming out the opposite side of the mix range. Interesting if you wanted to hear elements in virtual isolation, but hardly cohesive music! (Great for guitar lessons, though!)
The reel of tape that these tracks were originally recorded on would be called the "Master." Logically enough. But also logically enough, the tape deck spinning next to this multi-track deck, recording all this blended sound to a tape reel all its own, was also called the "Master" tape. In a sense, both terms are correct, but this redundancy can be hell on the archives.
Here in America, the multitrack tape is usually known as the "Multitrack Master," the tape the mix is captured on is called the "Master Mix," and the third reel - the one onto which the correctly sequenced and edited mixes are copied, is often called the "Production Master." Clear as this would seem to be, many studios are plagued with problems when they try to find the correct generations of various tapes (including Abbey Road!).
A multitrack master which has four full tracks on it can be mixed in as many ways as there are ways of hearing the discrete elements of sound in juxtaposition. It's all about preference, and, back in the day, it was all done "by hand," meaning that every element of that mix had to fall properly into place throughout, as it was being made, or else the whole process had to be repeated because of a mixing error made at any point in the song.
Mixing "live" like the Beatles did it can become just as much a performance as actually making the original recording. An alchemy occurs in mixing, too, and when that "golden" mix starts falling together, everyone in the control room knows it and starts to hold their breaths for fear that all their great work can be for naught if someone messes up a fader move during the remainder of that particular mix.
Often, if a mix was perfect up until a given point, another mix would be made and spliced onto the first one at a point just past where the first error happened, salvaging all that effort.
So, no sooner do you stop sweating your way through the live performance and tense overdubs of the master tape, then you begin another set of nerve-wracking performances called mixing.
All of this is highly collaborative, and all of this suspense has been effectively done away with in the modern computer age of recording, because every move the engineer makes while mixing is remembered by the computer and all those moves are then re-enacted by the computer on every subsequent playback.
Every tonal refinement is built-in, so that by the time the tracks are playing back with full mix automation, everyone in the control room is simply watching the faders zip around the mixing desk, perfection in motion. It sounds great, but one does come to miss that element of risk, of danger, of chance!
The Sgt. Pepper mults I heard on the radio were made in-house, I'm sure. And for what purpose - I'm quite unsure. Like I said when it first came up, I think it's in-house review material.
The only way to determine if there's interesting material hiding in your master tapes is to listen to every inch of them. It sounds a bit like they took every coherent separate element and made mixes of them. For example, the song Sgt. Pepper makes for a great, high-energy rhythm track, so it works to make a hot mix of just the band, in today's fidelity.
The mix that consists of mainly McCartney's lead vocal is exciting because it shows people what an incredible singer he was even when you take away his complimentary musical surroundings.
Sometimes the only way to properly hear a constituent track of a song is to do away with all the other parts and just listen straight through to that one track, a la the strings-only SHE'S LEAVING HOME, or the guitar-only Sgt. Pepper. The single part, in isolation, may not prove to be a thrilling listen all by its lonesome, but you never can tell until you've had the patience to do just that.
So I think they created "mixes" of the Sgt. Pepper album (quite possibly during the period of the album's actual gestation) which were intended simply as "reference" mixes. Reference mixes are those which are meant to just present a straightforward playback of one or more tracks - no fancy mixing layers, devoid of sound effects, not intent on being flattering so much as revealing.
Did Paul play good bass all the way through on that track last night? Isolate just the bass, make him a good quality copy of it, let him take it home, and soon he'll be back with his decisions on what to do next.
Like I said before, these would be the kind of tapes George Martin would take away to write scores for - all business, no gloss, just the facts, m'am. I also think the story you heard about these being from the Anthology era could well be true, because I'm sure they did a lot of this kind of breaking-it-down mixing as they chose the elements they used to create those " composite mixes" of several different takes of the same song.
Musical coherence was not the goal here. Fact-finding was. They wanted to know what they had "in the can" from this album. It didn't have to be pretty, and it often isn't, even when the end results are. For example, all recordings have "leakage" from the headphones getting onto the mic, especially vocal and solo acoustic instrument overdubs.
These ghosts of sound are normally swallowed up by the presence of all the mixed-in musical tracks, but they stand out a mile when you listen to a track of what that open mic is hearing while someone's waiting to sing! And when it's our boys waiting to sing, then things get pretty damned interesting! These are the nuts-and-bolts built into any album ever recorded, and, if you love the process, it never gets any less fascinating.
To answer a couple of your questions... These tracks, as they come to us, are technically in stereo. This is because the format they're recorded on is 2-track stereo, for CD or radio play. But the original Multitrack Masters can never be other than individual mono tracks. One sound on one track can only play back one physical signal.
True, single sounds can be treated through stereo f/x gear, and then they will seem to emanate from the full range of left-to-right. But that's only after the sound has been treated outside the realm of the master tape. Conversely, true stereo is achievable on a multi-track master, like so: I want to record a grand piano and, to reveal its full dimension, I want to incorporate the sound from the predominantly left-hand strings as well as give equal focus to the right-hand strings. I put a mic over the strings nearer to my left hand and record that to one track of the multitrack master, while at the same time I repeat this process on a new track with a separate mic to capture the right hand sound.
Upon playback, I turn the pan knob on the left-hand mic's track to the left, and pan the right-hand track to the right. The piano playback will now create the very convincing spatial illusion of coming at me from two distinct sides. This is a great sound, but was very rarely done back in the days of 4-track recording because no one had the tracks to lavish on such verisimilitude. About the best stereo recording attempted back then, was recording a drum set in stereo with two overhead mics and two separate tracks. But that was quite rare until the advent of 8-track.
Which leads to another point you mention: you'd heard that Pepper was recorded on two 4-track machines. That's both true and completely untrue. Allow me to save the description of multi-generational recording, a.k.a."bouncing" to Part Two of this treatise, which I now realize is becoming inevitable.
Pepper is definitely a multi-generational album, and that process is fascinating, and that process will be it's salvation should EMI ever choose to really remix it! The fidelity of the master tapes in those vaults will prove to be unbelievable. Experts will scratch their heads and say "How did they do that way back then?" when they hear the glorious quality of those tapes. And we'll say "How? They were the Beatles, son! Things got done!"
REDUCTION MIXES a.k.a. "BOUNCING - DOWN"
Reduction mixing is at the heart of the 1967 Sgt. Pepper methodology, brought about by necessity. Having been opened up to the creative possibilities of 4-track recording, the desire for a greater number of recordable tracks would have been enormous. And EMI's engineers responded with great exactitude and creativity.
The method for creating more than the apparent 4 tracks worked this way. The engineers filled the tape with the basic elements of a song. For example :
Track 1: Drums
Track 2 : Bass
Track 3: Guitars, Percussion
Track 4 : Lead Vocal
If the song still needed more parts, the solution was to take the 4 parts recorded and put them through the mixing desk, where they'd be shaped into a solid mix. That mix, now basically a stereo, left-to-right panorama, would be sent through the two main mixer outputs to either one or two inputs on a waiting twin 4-track tape recorder.
Sometimes all four tracks would be (boldly) combined to one track of the receiving machine. This meant that 4 tracks had now been "reduced" to one dense track on a fresh reel of tape on a new tape machine.
The original 4-track tape would now go into storage (remember this detail, it's very important), and all work hence would take place on this 2nd tape and second machine. The Beatles were very thrifty in their use of track space, so as many parts as were practical and compatible would be done on each new track.
If someone was to be doing a vocal, the backing vocals were often done at the same time, onto a 2nd microphone, but sharing the same track. Any instrument being overdubbed was likely to share its track with another one, say a guitar part being supplemented by percussion, or two keyboards being played at the same time, ala Martin and Lennon's duet keys on Mr. Kite.
Recording at this rate of density, the 2nd 4-track tape had to be filled up carefully before they ran out of new space. This apparently did sometimes happen, and then that 2nd generation tape would actually be reduced one more time to another waiting 4-track deck.
This process of copying some of the signals onto a 3rd tape generation (copying it 3 times) was a very risky one, as the quality of these copies would noticeably deteriorate, no matter how careful these masterful engineers were.
But when you do the math and figure out how many separate sounds would have been included in a given song by the time it had been reduced once or even twice, with 4 or 5 musicians contributing whenever possible, that would likely make for a very high track count. While they may have "only" used 8 or 10 tracks, they packed them as full as was humanly possible!
On the highly rare occasion when they tried to press two 4-track machines into service simultaneously (see Geoff Emerick's description of the orchestral sessions on A Day In the Life in his book Here, There, & Everywhere), they pioneered the first instance of two machines being locked together in sync, which was a process of mind-boggling frustration.
But it worked, and gave them the advantage of tracking the orchestral mayhem on that song four times, each recording of which could be later pressed into service when they were mixing the song. The main point of all these separate tracks would be that it was preferable to hold off the ultimate blending of individual songs until the last possible moment, so as to preserve the integrity of each sound.
From there, when the recording was finished, they would mix from the last 4-track tape used. The actual job of "bouncing" tracks down between two machines would go a long way towards refining the quality of the sounds, with many critical effects and edits having taken place during the transfer, so that the mixing process could be used to really concentrate on the proportions and aesthetics of the blended sounds.
And the Beatles did much of their critical mixing in collaborative sessions, with all members present, which meant that a degree of exactitude could be achieved which modern automation still draws inspiration from.
One of the most fascinating aspects of this work method is this : all those 1st and 2nd reels of 4-track masters still exist, carefully stored away at the moment they were done contributing to a reduction master. If the powers-that-be decided to create a deluxe, remixed, 5.1 version of Sgt. Pepper tomorrow, they would be working with the greatest treasure trove of master tape elements in existence.
Even as exacting an engineer as Geoff Emerick has gone on record stating that when he took these tapes out of storage to remix them for the Beatles Anthology in the mid-90's, he was absolutely stunned by a fidelity of sound he felt had still not even been equalled by today's recording techniques.
I think he can well be believed, since we've already heard those very multi-tracks, pristinely, on the Yellow Submarine Songtrack in 1999, and on the Love album last year. A marriage of the best of both technical ages, 1967 and the present, is about to be unveiled when the Beatles' body of work is re-released.
A re-mastered catalogue will be great enough, but if the technical team has finally been permitted to remix the masters and create modern reproductions of these mixes, or, dare I even say it, 5.1 mixes, then we will be in for the greatest single thrill in audio since, well, since this music was first released.
I think it's safe to say that, gorgeous as these albums sound to us, we've still never heard them play back as they did in the control room at No. 2 Abbey Road on the day they were made. With the technology we've now got available to us, that revelation may at last be just around the corner. And the better understood their recording accomplishments are, the better the Beatles will sound when the moment of truth arrives!