Doctor Who effects
Mike Bedford makes use an analogue synthesiser simulator to generate one of TV’S most iconic and recognisable themes.
Mike Bedford makes use of an analogue synthesiser simulator Amsynth to generate one of TV’S most iconic and recognisable themes – with a bit of tweaking to keep the copyright lawyers at bay.
Established in 1958, the Radiophonic Workshop was created, according to the BBC, to produce incidental sounds and new music for radio and television. It was known for its pioneering work in electronic music and music technology.
Just two years into the Workshop’s existence, Delia Derbyshire, who had recently graduated from Cambridge with a degree in music and mathematics, joined the BBC as a trainee assistant studio manager. Within a couple of years she’d been assigned to the Radiophonic Workshop. It was here that she famously produced the Doctor Who theme tune, which had been composed by Ron Grainer.
Delia had to use a mix of equipment including laboratory instruments like signal generators, in-house designed and built electronic circuits, and reel-to-reel tape recorders. Bizarrely, Delia even used metal panels, specifically blanking plates from 19-inch instrument racks, plucked by hand, to create the twang of the
Doctor Who base line. To produce different notes, the sound was recorded on a tape recorder and played back at different speeds to alter the frequency, and further electronically manipulated to subtly alter the fundamental sound.
Introducing amsynth
We’ll be using a real-time open source software synthesiser called amsynth, which is similar to classic analogue synthesisers of the 1970s, including the Minimoog and the Roland Juno-60. First install it on your PC and fire it up. Now click the Audition button towards the right-hand edge of the toolbar (which is a green forward-pointing arrow in some versions) and you’ll hear a musical note. What’s more, just by chance, unless they’ve been changed since the version we used, the default settings produce a sound that isn’t a million miles from what we need for the bass line of the opening few bars of the Doctor Who theme.
A key component in generating this sound is a ring modulator. You don’t need to understand the inner workings of this electronic circuit to follow the following instructions but, if you do want a better appreciation of the underlying principles, take a look at the explanation in the box entitled Understanding Ring Modulators
(opposite page). And finally, before moving on, note that, although amsynth has rotary controls, the user interface is linear so, to change any setting, click the control and adjust by moving vertically.
Pressing the Audition button gives us access to just a single note and there’s limited scope within amsynth to change that note. What we need, therefore, is to connect a MIDI piano keyboard to amsynth. If you have a real MIDI keyboard then that can be used, but a software solution involves using the Virtual MIDI Piano Keyboard
(called VMPK in repositories) and you also need a utility to wire its MIDI output to amsynth’s MIDI input – we used the ALSA Sequencer (aconnectgui in repositories).
Note that with VMPK’S default settings, when you use the keyboard it’ll play notes through its own internal audio generator and so you’ll have to tell it to route its output to amsynth. To do that you’ll have to define the necessary routing in the ALSA Sequencer and also, in VMPK, select MIDI Connections from the Edit menu and then choose ALSA from the MIDI OUT Driver menu. Now you’ll be able to play notes on VMPK and hear them via amsynth. Try it out, noting that the sound of the notes will now be very different to how
VMPK sounded before you wired it through to amsynth.
Create the bass line
With everything connected up, we can now start to make some music and we’re going to start by generating the introductory base line. Fred Welsh,
author of the Synthesizer Cookbook, reported that he reverse engineered the bass line using a harmonic analyser. To set up amsynth according to his instructions, here’s the gist of the settings that you need to make.
We suggest that you start with amsynth’s default settings, most importantly “[U] user bank” as the bank and “0: Derren 1” as the sound, because these aren’t too far from what we want. Set both oscillators to square/pulse wave using widths of 30 per cent. Set Oscillator 2 to an octave below Oscillator 1. Select lowpass as the filter with the 12db option and the cut-off frequency nearly all the way down, and set its envelope to A=0 sec, D=250MS, S=25 per cent, R=250MS. Set the amplitude envelope to A=0 sec, D=650MS, S=0 per cent, R=700MS.
Although not specified in Welsh’s instructions, we suggest starting with a 50:50 mix between the two oscillators and the degree of modulation set to at least 50 per cent. You might try nudging up the Detune control for Oscillator 2 very slightly, certainly not too far, and you could even try tuning Oscillator 2 down another octave.
Having made those changes, click Audition to try it out. Depending on which of the many versions of the theme that have been produced over the years you think of as the true Doctor Who music, this might not sound exactly as you remember it, but it’s close enough for now. In fact, Fred Welsh says that this is the version used in the 70s during Tom Baker’s time as the Doctor. If you want to fine-tune it later, it’s almost certain that
amsynth will be able to better meet your expectations, although bear in mind that there’s an almost infinite number of combinations of the settings.
Follow the notes
Now it’s time to use VMPK to define the melody and rhythm of the base line which means following the music reproduced (see above right). If you’re not au fait with music notation, we’ve labelled the music in red with the pitch of the notes as related to the five horizontal lines, which are collectively called the stave. The pitch is represented by the letters A to G, which repeat every octave.
To fully define a note, therefore, the letter A-G is followed by a number that defines the octave. Bizarrely, octaves start with C, not A, so the note below C4, for example, is B3. As you’ll see, the pitch of the notes increases as you move up the stave, and are alternately on the lines themselves and the spaces between them. The position of a note relates to its body, that is the blob, as opposed to the vertical stick which is attached to some notes, including all those in the opening section of the base line.
It should now be clear that the bass line starts with E3. Note that this segment of music has a so-called bass clef (which looks a bit like a backwards letter C with two dots after it) at the beginning of both lines, but the mapping of notes onto the stave is different for the other common clef, namely the treble clef. In fact, although we’ve provided just a single stave, music is commonly shown as two or more staves, one above the other, which are played in parallel. Indeed, the complete
Doctor Who theme tune would have to be shown as several staves and we’ll see one of the others later.
While the position of the note’s body defines its pitch, the form of the body and the form of any stick defines its duration. In the music we’ve presented, there are notes of only two durations, called crotchets and quavers. Crotchets can be thought of as having a duration of one time unit and are the notes with just a straight stick. Quavers have a duration of half a time unit and have a stick with a curved tick on the end. However, when multiple quavers appear one after the other, they don’t have ticks on the stick but, instead,
Another classic Doctor Who sound effect to try out is the noise of the TARDIS dematerialising. Oh, and if you’re wondering, it’s been attributed to “the wheezing of the time rotor, possibly because of the Doctor leaving the handbrake on”. look rather like crotchets joined together with a horizontal bar.
A further complication is that each time a quaver is used in the particular music that we’ve reproduced. It’s part of a triplet, as indicated by the figure 3, which appears above or below either a group of three quavers or a crotchet followed by a quaver. This modifies the timing so these groups of notes, which would otherwise have a duration of one and a half time units, have a duration of just one.
Furthermore, the curved line, called a tie, effectively ties two notes together. In the music we’ve reproduced, there’s a tie in three places between a single quaver and the first quaver of a triplet. This shows they’re merged as a single note, as opposed to two separate notes.
The final thing we need to say about music notation is that music is divided into bars, which are terminated by a vertical line, and the beat is on the note at the start of each bar. The number of time units in a bar is defined by the time signature which comes near the start of the music just after the clef. Here, the time signature is “fourfour time”. It’s indicated by the two figure 4s, one above the other, and it means that a bar has four time units.
Now you need to know how the notes map onto a keyboard, but if you’re not familiar with the layout of a piano keyboard, can label the keys. To see these labels, select Note Names from the View menu. With the key labels in place you can have a go at playing the base line from the musical score provided.
In our experience, the mouse isn’t fast enough to play the music at its normal speed. However, the QWERTY keyboard can map onto the piano keyboard and will operate at a sensible speed, but you’ll have to try it out first to get a feel for the mapping. With a bit of practice you should soon be able to play the pitch of the notes correctly – after all, the bass line doesn’t have very many different notes, even though getting the hang of the timing is often more difficult. Fortunately, in this case, you’ve probably got a good idea of how the music is supposed to sound. Also, the phrase “dum-di-dum” has been used as useful a way of describing the rhythm of the block that appears twice in each of the first two bars, “diddly-dum” is the rhythm that appears twice in the third bar, once in the fourth and elsewhere, and “dum-dum-diddy” describes the rhythm of the second half of the fourth, sixth and eighth bars.
Add the doo-wee-ooh
If you want to continue with the bass line, you can use the techniques we’ve already seen, but you’ll need the music for more of the theme tune so we suggest that you consult www.dwtheme.com. However, we’re now
going to look at how to add another recognisable part of the tune, the part that has been described as the “doowee-ooh”. This differs from the bass line both in the characteristics of the tone produced by the synthesiser and by the fact that it involves a technique called portamento or glissando, in which one note merges into one of another pitch. This can’t be achieved, for example, on a piano that only allows discrete notes, separated by a tone or semitone, to be played.
Ideally, you’ll want to fit this in with the bass line and this can be done using multi-tracking. You can do this by recording the base line in Audacity and then playing it back while you generate and record the “doo-wee-ooh” in time with the first track. This is a standard technique so we’ll have to leave you to read up on how to use
Audacity in this way.
As with the bass line, we’re providing a snippet of music for this part of the theme (see facing page), although it doesn’t last as long as the base line. Instead of a bass clef, this stave has a treble clef (the curly symbol that actually evolved from the letter G) at the beginning. The notes map differently to a stave with a treble clef so, again, we’ve labelled the music in red.
You’ll notice that there are some notes that appear below the stave. In fact, middle C (C4) is always shown on its own bit of horizontal line which, in piano music that has a treble stave above a bass stave, sits between the two. In this case, though, to avoid the need to reproduce the two staves, we’ve also represented some notes below C4 on their own bit of horizontal line which, in reality, would be the top line of the bass stave. So, for example, the first note is B3 and the final crotchet is A3. Notes above the stave follow the same principles.
You’ll see that we’ve introduced a new note duration, represented by a hollow blob with no stick. This is called a semibreve, and has a duration of four time units. The sloping lines with “gliss” against them represent glissandos. Note that although the third bar appears to represent more than four time units – this is because it has two parts. In other words, the downwards glissando doesn’t play after the semibreve but plays in parallel with it. And finally, the block symbol at the start of the first bar is called a rest, specifically a minim rest. It’s like a space in text, in this case lasting two time units.
First of all, to play this key part of the theme tune alongside the bass line that you’ve already recorded, you need to know that the first glissando kicks in about the time of the “dum-dum-diddy” in the sixth bar of the bass line, and the second glissando plays in parallel with the final “dum-dum-diddy”. Second, while we’ll leave you to fine-tune the sound in amsynth, we suggest you base it on sine waves. Next, adjust the Portamento control in
amsynth to select the time it takes for one note to glide into the other –this will take a bit of experimentation.
Now you can try it out yourself. You don’t want to dwell on the first note before it glides up, so play the two notes with as short a time between them as possible. The same applies to the other glissando. We found that there weren’t enough notes mapped by VMPK onto the QWERTY keyboard for the approximately two octave glissandos. However, you can edit the mapping or add extra keys at Edit>keyboard Map. You might also need to alter the Base Octave. Annoyingly, though, it isn’t possible to continue the note represented by the three tied semibreves through and beyond the second glissando. Despite its apparent simplicity, you’ll have to play the melody in two parts and then mix them.
Over to you
There’s so much more we could say, but part of the fun here is learning by experimenting so we’ll leave you to add as much or as little as you want to these basic foundations. An obvious next step is to add the ambient sounds that can barely be described as music but add so much atmosphere. We’re inclined to think of them as sounding like steam, but they’ve also been described as wind or wave effects, or even bubbles and clouds. We suggest you use a sound with a high percentage of noise waveform.
Finally, although it didn’t make an appearance in the original version of the theme, how about adding the so-called sting which introduced so many variants of the Doctor Who theme, drawing us in with its ethereal sound even before the very first “dum-di-dum”.