Voice Tutorial

This tutorial is in the form of a few basic exercises. They are intended to be followed in sequence, but feel free to advance to the later stages, or return to an exercise you found difficult, if you think it will help.

Exercise 0 Are You Ready for this Tutorial?

Let us begin by attempting to make and maintain a single note for ten seconds. This should be as close as possible to a sine wave; aim at a frequency of around 1000 Hz.

Once you have achieved this, I want you to use your tongue to cut the note off as instantaneously as possible. Do not allow the frequency to change as you cut the sound off, and remember that too slow a tongue movement will also bring about a noticeable transition in harmonics. Do not be tempted to stop blowing in order to end the sound, as this will inevitably lead to a drop in frequency.

How did you do? If after more than three attempts you find you are unable to maintain a single clear frequency, or that you are unable to cut the sound off without any frequency transition by the tongue method, you are really not ready for this tutorial. You should enrol on one of my full-time courses to get your basics up to scratch.

If, on the other hand, you found this exercise very easy and got it right first time, you may be ready to enrol on one of my DhD (Doreen higher Diploma) courses. Most of you, however, should proceed with this tutorial.

Exercise 1 Amplitude Modulation

Perfecting this technique will allow you to carry out basic communications via the telephone network, although without the more advanced techniques, the full range of speeds and applications will not be available to you.

In Exercise 0 we perfected the sine wave and the instantaneous cutoff without frequency or harmonic transition. Now I want you to try something a little more difficult. Maintaining the air pressure, I want you to release your tongue to allow the note to recommence. Again, we want this to be instantaneous.

At first you will probably find that it is almost impossible to begin on the right note. Most likely the pressure will be too low, in which case the note will rise noticeably before reaching the desired frequency. Occasionally you may overcompensate and have the reverse transition.

Although it is not entirely necessary in amplitude modulation, an instantaneous start at a set frequency is a basic skill you will have to develop for all other techniques. Although it is one of the most awkward to learn, with practice it will soon be the most natural thing in the world.

The instantaneous switch from sound to silence, and the more difficult one from silence back to sound, however, are crucial. As soon as you can manage both once, I want you to try doing it several times per second.

This may seem impossible, but you will discover that we budgies are naturally capable of several hundred stops and starts per second. Once the technique has been mastered, increasing the speed is relatively easy.

Exercise 2 Frequency Modulation

This lesson is useful in its own right, but is also an important stepping stone to other techniques.

For the time being I want you to forget the stop and start techniques you developed in the previous exercise. For now we are going to concentrate instead on instantaneous changes of sine wave frequency.

As a member of the bird family (obviously a rather senior member) we are blessed with a highly sophisticated lung system. Unlike our people-pets, who merely blow air in and out, we are able to maintain a circulation of air with the help of special air sacs.

You need to be able to maintain tight control over these air sacs in order to produce an effectively continuous flow of air through your flappily-dappilies. You will need your tongue again, however, to switch the flow from side to side.

Try this for a while, don't worry about frequency at first, but make sure you can make that instant switch from side to side without reducing the air flow. Once you have got this right we are ready to move on.

I want you to make the flappily-dappilies on one side twice as tense as on the other (it doesn't matter which side: whatever you are comfortable with). If your sine wave earlier was at 1000 Hz, by directing the air at the tenser side only you should be able to produce a sine wave at 2000 Hz. If you now apply your instantaneous side-switching technique, you should already be producing an instantaneous frequency shift. Try increasing the rate at which you do this, again to several hundred times per second.

Exercise 3 Phase Modulation

You should by now have achieved independent control over your left and right flappily-dappilies. For this exercise, I want you to go back to having both sides at an appropriate tenseness for 1000 Hz, but only by relaxing from total stiffness at exactly the right moment.

This may be difficult to understand at first, but what we are going to do is practice relaxing them from total stiffness to a tenseness of 1000 Hz about half a millisecond after the side shift. This will result in an effectively continuous 1000 Hz sine wave with a change of phase.

When you can do this several hundred times per second, I want you to try and make a distinction between, say, 500, 250 and 125 microseconds of delay before relaxing the total stiffness. The different angles of phase change can be used to increase the rate of information you are able to transmit per second.

Although it is not really appropriate for this tutorial, I will mention at this point that I often use a special technique of advancing the phase by using a special breathing method to get the flappily-dappilies on one side vibrating a fraction of a millisecond before the others have stopped. This further increases the amount of information that can be transmitted per second. Tuition in this technique is available at DhD level.

Exercise 4 Asynchronous Transmission

Synchronous transmission, the kind I tend to use to further increase my transmission rate, is beyond even most DhD schemes. It is very unlikely that you are able maintain exactly the same rate for long enough to synchronise with the receiving modem, nor to be able to interpret the information you receive from anyone else who is thus encouraged to transmit in the same way.

Instead you must simply transmit start bits and stop bits, using the techniques we have already covered, depending on the method of transmission. All you have to be able to do is maintain a constant rate for the duration of each character.

If you are convinced that you have the necessary timing and that you can learn all the necessary ham, pork and bacon codes, I do offer courses in this area. For now, however, I suggest that you go away and make sure that you really have something to say before transmitting it to anyone.

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