About This Theme

The original theme is composed in the key of E, predominantly in the Phrygian mode. The theme runs at a tempo of approximately 140 beats per minute, but the hand-edited nature of the theme's realisation means that the exact tempo varies continuously throughout the theme.

Components

Derbyshire and Mills used musique concrète techniques to realize Grainer's score. Each note was individually created by cutting, splicing, speeding up and slowing down segments of magnetic tape containing recordings of a single plucked string, white noise, and the simple harmonic waveforms of test-tone oscillators (normally used for calibrating equipment and rooms, not creating music). The swooping melody and pulsating bass rhythm was created by manually adjusting the pitch of oscillator banks to a carefully timed pattern. The rhythmic hissing sounds, "bubbles" and "clouds," were created by cutting tape recordings of filtered white noise.

Bassline

As discussed in the Bassline section, the bassline is comprised of two layers.

The first layer of the Derbyshire bassline is most commonly described as a plucked string sound. It is believed that this sound was created using a steel guitar string mounted on some kind of electronic trunking cover or similar extruded piece of metal. The string was plucked and the sound recorded onto tape and heavily manipulated. A low sub-octave is also present in the bassline, which lends additional bass frequencies to the mix. From the recorded plucks, each bassline block was constructed by splicing separate pluck "samples" together into dum-de-dums, diddly-dums, and dum-dum-diddies. Each block uses two different samples, which makes them sound more natural and prevents them from becoming repetitive, but each block of the same type is the same for each pitch (for instance, all E diddly-dums are identical).

The following list denotes the samples used for each block, with "2" denoting a slightly more dominant note than "1." The samples are relative to each block, meaning that a sample marked "1" on one block is likely not the same sample marked "1" on another block.

Dum-De-Dums The E dum-de-dum is 2-2-1. The G dum-de-dum is 1-2-2. The B dum-de-dum is 1-1-2. The D dum-de-dum is 2-1-2

Diddly-Dums The E diddly-dum is 2-1-1-2. The B diddly-dum is 2-2-2-1. The low G diddly-dum is 1-1-2-1. The C diddly-dum is 1-1-2-1.

Dum-Dum-Diddies The G high-low dum-dum-diddy is 1-1-2-2. The B low-high dum-dum-diddy is 2-2-1-1. The D high-low dum-dum-diddy is 2-2-1-1.



There are also some subtle variations present throughout the bassline. For example, the second G dum-de-dum in the bassline intro is notable as there is a slight bend upward as it begins. Additionally, the B, low G, and C diddly-dums are notable because the final note is less pronounced than it is on the E diddly-dum, producing more of a "duddle-uddle" sound.

The second layer, also discussed in greater detail in the Bassline section, was created using Jason valve oscillators to provide a swooping grace note lead-in to each bassline block. Put very simply, the second layer leads into the root note of each bassline block from the note below it in the scale. This is only a general guideline, however, and there are several occurrences of the second layer throughout the theme that differ.

The most notable examples occur during Melody 2, when the theme shifts from E down to B, where the second layer bends from D down to B (instead of A up to B), and during the bridge, which tends to follow its own rules. The key difference in the bridge, after the initial bend (which bends downward from A to the low G), is that every second layer section begins on the root note just below the G (which in this case is F#). This continues until the bassline has returned to B, at which point normal second layer notation resumes. The only other notable difference in the bridge is that, for the D dum-de-dum, the second layer bends from F# down to the D below it, rather than up to the D above it.