Sound Module & Sampler Topics:
» Who Samples Anymore, and Why Do I Want A Sampler?
» Sound Modules, The Songwriter's and Composer's Tool:
» Synthesis Basics: What are all those knobs for?
» What to look for in a pro keyboard

Who Samples Anymore, and Why Do I Want A Sampler?

With all of the Sound libraries available from so many companies, recorded in world class studios, why would anyone want to take the time to sample, and who does?

Sound Design:
If coming up with sounds that are unique and completely original is your passion then sampling capabilities are necessary, especially if you work as a sound designer in film or TV, or hope to one day. Not all sounds that are currently available in sound libraries will work for your specific needs. You may also be asked to come up with something no one has hear before, or you budget will not allow the purchase of additional sound libraries. Besides, who has the time or money to buy every available library and go through the sounds, one at a time? It's easier and more rewarding to create your own.

Studios:
You've spent hours upon hours recording that drum kit; tuned the heads, found the right combination of mics, placed them at just the right distances, through the right combination of preamps, compressors and gates with just the right settings for each. You've got your signature drum sound. Wouldn't it be great if you could sample the kit and trigger the sounds anytime you wanted, or sell them to others as your sample drum library?

Electronica / Groove Production:
Composers of electronica will find samplers useful, especially if they have created a big, lush layered sound with a number of synths, and would like to be able to free up some sound processing by sampling the entire combination and save it as a patch. Again, the concept of being completely original figures in greatly in this genre. The same holds true for groove production, where it is essential to come up with signature sounds, like a big phat kick drum that no one else has. Usually, it's customary to layer up to five (or more) kick drums or snares with different EQs and effects for each. The easiest way to reproduce that sound while saving voice allocation and disk space is simply to sample your unique creation and use it as easily as you would any patch sitting in a beat box or synth.

Sound Modules, The Songwriter's and Composer's Tool:

If you already have a good keyboard controller or workstation and you'd like to add to your sound library without taking up the space another keyboard (which you don't need) would, then sound modules are the way to go. A good example of this would be a Triton Extreme 88 owner who wants the sound of the Roland Fantom X, but doesn't need two big workstations; the rackmountable Fantom XR is the solution.

The sound module is useful for expanding your sound library, but why is it of particular use to songwriter's and composers? This answer rests in the following question; "How do you want to spend your time, programming synths or writing music?" With all of the options and features the average synth now offers for sound creation, it's easy to get lost in a sea of options, especially if you factor in the myriad options that a software DAW such as Digital Performer have to offer. The choices can become downright immobilizing. In order to get to the business of writing music, it's best to set limits; Spend your time where your strengths are. It's easy to spend hours fiddling with knobs and soft keys while bent over the rack trying to scroll through all those sub-menus in that little display in order to create a sound that ultimately winds up not being that much different from the one you started out with, or one that you simply find yourself erasing and starting over. In the meantime, that hit song or film score remains unwritten. With sample players, you can set up your sounds in a way that will enable you to get to work, and leave the programming to the tweak-heads. Often times, sounds created by people with a knack for it can be downright inspiring and will spur you to creativity. Sometimes a sound alone can suggest a piece of music, or a musical direction for the composer or songwriter to explore. On the other hand, if you feel that you're music needs a truly unique sound and you haven't found one in the hundreds of thousands of available patches out there, your synth module will grant you access to more than enough of its inner architecture to create one based on the many resident samples, waveforms and other sound-manipulation functions within it.

Synthesis Basics: What are all those knobs for?

If you are considering a Table Top synth or analog modeling synth (the two are often combined), then you're already interested in tweaking sounds, since the point of Table Top synths is to out the controls of an analog synth right in front of you, or setting comfortably on your DJ coffin. If you are new to synthesis, you may wonder what all those knobs and sliders are for. There are a number of terms you will hear and see in synthesis that can be quite confusing, such as LFO, which means Low Frequency oscillator, not UFO's that have landed, ADSR, Envelope, Cutoff Filter, Resonance, and more. Rather than write a book on the origins and development of synthesis, we have compiled a handy little glossary of terms and controls of analog synthesis.

Oscillator

An oscillator operating at sub-audio frequencies is often referred to as a low-frequency-oscillator (LFO). Analog oscillators generate an electrical function or waveform. These are typically approximations of simple trigonometric shapes such as sinusoidal, (sine wave) square, triangular, and pulse. More sophisticated synthesizers will permit the user to mix different waveforms and to process them in various ways such as modulating the pulse width or altering the shape in some other way, Digital oscillators can generate these same shapes using mathematical descriptions or look up shapes from a table and generate arbitrarily complex shapes.

Oscillators can be used to generate a wide range of frequencies including the audio spectrum. These can be combined together to create more complex timbres (additive synthesis) and can be used to modulate other parameters such as another oscillator's frequency (frequency modulation) or amplitude (amplitude modulation). A digital oscillator may use a portion of sampled sound as a waveform.

Waveform: The waveform of a signal is a graph of its instantaneous voltages versus time. In audio, for example, we are always dealing with periodic waveforms that make up what we hear. These periodic waveforms can be plotted on a graph and will show up as some type of squiggly (how's that for a word?) line. From left to right is time (usually a very short slice of time) and from top to bottom is the amplitude of the sound (or relative voltage) at those instants in time. The familiar sine wave is an example of this.

Waveforms, or Waves (a Wave File, for example) are also the names sometimes given to samples or snippets of sound that are used in various electronic sound generating or playing instruments. The usage of the word comes from the definition above and has become commonplace in the modern day era of audio production where one is often looking at waveforms on a computer screen while editing sounds.

Sine Wave: a continuous, cyclic waveform in which the amplitude (or instantaneous voltage) varies according to the sine (a trigonomic function) of the time. It is unique in that it has no overtones whatsoever. Since it contains only the fundamental pitch it gives a smooth rounded tone. Test tones used to calibrate tape machines and other equipment are generally sine waves. In acoustic instruments a flute sometimes has a nearly sinusoidal output. On an oscilloscope a sine wave looks like a symmetrical wavy line.

Triangle Wave: Like sine waves and square waves, triangle waves are commonly found and used in audio production, and they are a common waveform source on synthesizers. A triangle wave's shape is characterized by a linear increase or decrease in amplitude over time, followed by a linear change in amplitude at the same rate in the opposite direction. As indicated by its name, this wave has a triangular shape when viewed on a plot referenced to time. Sonically triangle waves exhibit a strong fundamental with relatively weak, odd numbered harmonics.

Square Wave: A waveform shape with squared corners. Unlike the continuous nature of sine waves, square waves have very fast (infinitely fast in theory) rise and fall times with periods of steady state voltage at the top and bottom.There is no way for a theoretically perfect square wave to exist because in practice it always takes some amount of time for the voltage swing from the bottom to the top (and top to bottom) to occur. A waveform shape does not have to be a perfect geometric square to be considered a square wave, but in general they do approximate the shape. In practice we tend to call many waveforms that have really fast rise and fall times with roughly equal periods of steady state between them square waves, though there are some other more specific (and correct) names for a few of the variants. Square waves are used in all kinds of digital equipment because they are ideal for representing the ones and zeros of digital. They are also used for clock and other data signals as well as certain types of audio signals. In audio, square waves have a very specific type of harmonic structure and thus a very distinctive sound to them. An instrument such as the clarinet naturally creates something very close to a square wave, and in synthesizers square waves are used to emulate clarinets. Also, a sine wave that is in severe clipping begins to take on a square like quality. In fact, most waveforms (even very complex ones) begin to exhibit some of the characteristics of square waves under severe clipping.

Pulse Wave: A waveform type that's similar to a square wave. Pulse waves are more rectangular and tend to be more "tall" than "wide," which is why they are called pulse waves; they are more like a series of pulses. Pulse waves have a very high degree of harmonic content and have a characteristically "hard" sound.

VCF (Voltage Controlled Filter): A VCF is a filter in an analog synthesizer that changes the cutoff frequency (in a low pass filter or high pass filter), or the center frequency (in a band pass filter) according to the amount of a control voltage. Controls may include cutoff or center frequency (depending on filter type), slope, bandwidth and resonance or Q. All or some of these may be voltage controllable.

Cutoff Frequency: In a filter, the cutoff frequency is the point where the response is 3 dB down in amplitude from the level of the passband. Beyond the cutoff frequency, the filter will attenuate all other frequencies, depending on the design of the filter. On a sweepable shelving EQ or filter, what you are "sweeping" (or changing) is the cutoff frequency. To our ears, this changes the point at which the filter is operating.

Resonant Frequency: The frequency at which resonance occurs. The resonant frequency determines the pitch of things like recorders and other musical instruments that rely on resonant columns of air. It also determines the pitch of feedback, another form of resonance. And it is the pitch or frequency the port of a loudspeaker may be tuned to.

Q: The resonance of an electronic circuit;, "Q" actually refers to quality factor. Q is a measure of the sharpness of a resonant peak. The term Q is often used interchangeably with "bandwidth". This is not entirely correct. It is more accurate to say that Q determines bandwidth (a subtle but distinct difference). Q is most often used in reference to synthesizer filters (sometimes referred to as resonance) and equalizers, but it also applies to capacitors (a measure of efficiency, the ratio of capacitive reactance to resistance at a high frequency) and speakers (a measure of directivity). In speakers, a Q of 1 means the system sends out energy equally in all directions; a speaker with a Q of 2 radiates in a 180 degree hemisphere; higher Q's correspond to smaller angles. In EQ circuits Q is defined as the center frequency divided by the half power bandwidth. On a 1/3 octave graphic equalizer, for example, the half power point at 1 kHz is 232 Hz wide. The Q is thus 1000/232 or 4.31.

VCO (Voltage Controlled Oscillator): An oscillator in an analogue synthesizer which changes its frequency according to changes in a control voltage.

Standard is usually 1 volt = change of one octave.VCOs may have:

• Outputs: various waveforms: sine, pulse, triangle, sawtooth
  
• Output controls: for coarse and fine frequency, wave shape (such as pulse width) and output level as well as
  
• Inputs: synchronization to another oscillator, pulse width (for pulse width modulation) and frequency modulation
  
• Input controls: for control voltage attenuation, synchronization to another oscillator, and frequency modulation

Envelope: In sound and synthesis, the envelope is the variation that a sound exhibits over time - basically how a sound starts, continues and disappears. It is comprised of concepts such as attack and decay, but other sonic distinctions such as transient and sustain may also be applied in some circumstances. Pitch, timbre, and harmonic content (which is basically timbre) can also change over time and in some cases are considered part of the overall envelope making up a sound.

VCA (Voltage Controlled Amplifier): A VCA is an amplifier in an analog synthesizer that changes its amplification according to the size of a control voltage.

For example:
0 volts = no signal,
10 volts = maximum amplification of the signal.

ADSR (Attack, Decay, Sustain, Release ADSR): A simple reduction of what is generally a more complex dynamic envelope. In synthesizers or samplers it may be used to control amplitude, filter cut-off, or tuning (to name a few likely parameters). In older analogue synthesizers, the ADSR created a transient control voltage, which was used in conjunction with a voltage controlled amplifier, filter or oscillator. It required a trigger to turn it on. In more contemporary models it often refers to both the envelope and the process. In most applications the attack, decay and release segments have preset durations while the sustain segment gets its duration from the trigger. This is based on the model of an organ which will sustain as long as the key is depressed.

• Attack: in audio terms, the beginning of a sound. What type of attack a sound has is determined by the sound's attack time, or how long it takes for the volume of the sound to go from silence to maximum level.
• Decay: the rate at which the maximum level goes to a steady level.
  
• Sustain: the duration of the steady level.
  
• Release: once the key is released, the time it takes for the 'sustain' or steady level to decrease to a zero level.