Beginners Guide To Synthesis
What is Synthesis?
Synthesis is the creation of sounds/synths. This can be done via a synthesiser, a synthesiser is a keyboard set out with various switches, dials and knobs, these would change the way a sound is presented by altering the pitch/frequency, waveform and the amplitude etc (I'll explain all of these). The digital equivalent will have pretty much all of the features of an analogue synthesiser (perhaps more), however, most of the digital synthesisers are not accompanied by a keyboard, which may make things more difficult for the producer as they don't have access to the keys right in front of them, unless they have the MIDI keyboard installed to their DAW. Every producer would need to learn the fundamental aspects of synthesis to apply to their constructing of a track, they need to know and recognise certain elements of a synthesiser (be it in analogue or digital form) so they are not spending their studio session pressing buttons hoping for a decent synth, being educated in this respect will make their producing process a lot quicker.
The Basic Wave Shapes
Frequency/Pitch
Frequencies operate at a certain amount of vibrations per second (we call this Hertz or hz) so when I say 40hz it means that the synth, instrument or sound performs 40 vibrations per second. The human ear can hear from around 20 Hz to 20,000 Hz or 20 kHz. Anything above or below this is only identifiable by using technology.
ADSR
ADSR stands for Attack, Decay, Sustain and Release. The ADSR gives a producer the ability to edit their synth's appearance in the their track rather than just its fundamental sound (this they would create in a basic synthesiser) although the ADSR is considered a big contribution to the creation of the synth. The attack represents how long a producer would like their synth to sound before it reaches its peak, for example, a long drawn out attack could create a sweeping effect in a producers synth. The decay indicates how long from the moment a synth reaches its peak to the point where it remains at its fundamental level (sustain), this could be used,in conjunction with the long attack to create a sweep down effect drawing out the synth. The sustain function allows the producer to control how low or high they wish for their synth to present itself (amplitude-wise). This is something similar to what you would find on a basic synthesiser's volume/amplitude controls, but this is used in relation to the other functions of an ADSR and would fit better and blend well with them. As stated, the use of a sustain function is similar to a volume function so it allows the producer to conrol how loud they wish to present their synth. Finally, the release option allows the producer to design how long it takes for their synth to "drift off" or finish after the note has been performed. A good way to use this function (and a way that I use a lot) is to use minimal amounts of release, leaving a sharp, quick end, this is perhaps good for EDM drops. The opposite could also be done to give the synth a reverberated, echo-y sound. The ADSR gives a producer the ability to edit their synth even further and perfect their track even more.
Bibliography:
http://thedawstudio.com/Tips/Soundwaves.html. Accessed 12/11/2014. Ben Harris.
Music Technology and the Project Studio: Sythesis and Sampling, Dan Hosken, Accessed 12/11/2014.