From the very beginning of the Nightwaves zine in 1999, one of my biggest supporters and contributors has been my good friend
C.S. Graves. He shared his expertise on electronic music in a series of articles that he wrote which were subsequently published
in the zine. On this page, I will dig into the vaults and feature some of his articles that he wrote. I hope to eventually
feature all of his articles on this page, so keep checking back for additions.
CLASSIC SYNTH CORNER:
I was walking through a local music store one day in 1996 expecting to see only new and expensive keyboards I could never
dream of owning, then something got my attention. It was an incredibly dated looking machine, with its big colourful buttons,
its switches, knobs and sliders, and most of all its wood panel sides. WOOD! ON A SYNTHESIZER! I also chuckled when I saw
the word "compuphonic" in computery letters on it.
"Oh yes," I thought sarcastically, "this is sure to be state of the art!"
I immediately imagined some 60's B-movie mad scientist twiddling at the controls of this arcane keyboard, no doubt making
good-old-fashioned space noises to be heard in galaxies far away. This was my first impression of the Roland Promars (also
known as the MRS-2), which was released in 1979, for a hefty price of almost $2000US. I've heard tell that it's considered
a little brother to the Roland JP-4.
I looked at the price tag. $189?! My mentality at the time dictated that anything good had to be expensive, so I wasn't
convinced this squat little synth would be worth its relatively low price.
Still, I was compelled to listen. The music guy who looked like Jay Leno with a perm set it up. I played a few keys. I
was struck by the "juicy" quality of some of the sounds, which I didn't know at the time was characteristic of analogue synths.
I played a sustained note of the SYNTH-I preset and turned a knob labelled "brilliance". When I heard that lowpass filter
sweep, I knew I had to buy this thing. I had heard a similar sound on a Juno Reactor remix that had turned me on to the glories
of analogue. This was the type of sound and modulation I couldn't get on my digital boards, it was a resonant, hands-on experience.
I bought the Promars that day and it has been used in much of my music ever since then. It's got a main oscillator, a squarewave
sub, and a VCO-2 switch for selecting one of two tunable secondary oscillators, good for detuning or setting at harmoninc
intervals. You've got the standard sawtooth and squarewave, as well as a pulsewave that can be modulated with the LFO. The
LFO itself has sine, square, and two sawtooth waveforms. The filter envelope polarity can be reversed. There are three switches
to select any combination of bend or modulation for VCO, VCF, and VCA controlled by the joystick, as well as two knobs to
set the range of the bend/modulation (alas, my model makes a little fuzzy noise when I use the joystick). There's CV/Gate
inputs and outputs on the back so it can be sequenced or synced to other CV boards. Last but not least is that wonderful brilliance
knob, which has been fingered oh so much over the years. With a MIDI-to-CV converter driving a fast 16th note run into the
Promars, my hands are free to twist and turn it with near-orgasmic delight. And when the programmable bank is selected, all
of these parameters are ready to be tweaked in realtime.
This thing can make some of the standard noises, as well as ones that defy narrow dancefloor convention. The Promars may
not be the most well-known or sophisticated synth of the analogue era, but it's cheap, user-friendly, nice to look at, and
sounds great. That makes it a classic in my books.
Sample Start Modulation: What it is and what you can do with it
If you own a sampler or a wavetable synthesizer, it's just possible that you might come across a sound editing option called
sample start modulation, or offset. It may sound all very mysterious and esoteric at first, but this option opens up some
interesting possibilities for creating or modifying a sound once you understand it.
Let's suppose you've sampled a voice saying "A B C D E" (or that your wavetable synth has such a sound onboard). Sample
start modulation will change the point where the waveform begins playing. With the start value at zero, the sound will begin
at "A", at a value of 50%, the sound begins about halfway through "C", et cetera.
But this kind of modulation has far more musical uses than the example above. Imagine now that you have a sample of an
instrument with a strong attack. It could be a piano, a resonant synth bass, chiff flute, anything where the sample starts
loud or bright, and then fades quickly to a quieter or less bright tone. You access the sample start modulation section of
your sampler/synthesizer. By changing the sample start values you will be able to hear the effect it has on your chosen sample.
The piano, synth bass, or flute will all grow smoother or more percussive sounding as you change the values.
At this point you may notice an annoying pop that occurs occasionally when the sample start is changed. This is a result
of the sample starting at a point of relatively high amplitude in the waveform, which causes something like digital clipping,
or distortion. If you're like me and consider this effect undesirable most of the time, here's a simple trick to get rid of
those pesky pops. Go to the envelope section that controls amplitude. If you've never been in this part of your keyboard or
rack, don't worry, the following should be fairly easy to do. Find a parameter called attack time and set it to its lowest
value above zero. What this does is create an ultra-fast fade in at the start of the sample every time it is played, and should
take care of that unwanted popping.
Now, assign a modulator for the sample start, the varieties of which may vary from one machine to another. This could be
the mod wheel, key velocity, CV pedal, LFO, random or noise modulation, to name some common examples. Make sure though that
the one you use doesn't affect another parameter such as LFO depth or volume, which may interefere with the desired effect.
With your modulator chosen, put the sample start point back to zero and turn a parameter called modulation amount. This will
control how much the modulator changes the sample start point. A value of about 75 to 99% tends to yield the most dramatic
results. Now as you turn the mod wheel or hit the keys with varying velocity, the attack of your sound will change in nifty
ways as you play. Experiment with different samples, modulators and values. You might even want the sample to start near the
end with the modulation amount having a negative value to bring it back towards the beginning. It's all up to you.
Hopefully I have been more helpful than utterly confusing, and you'll be breathing new life into your own samples and/or
CANCELLATION and INVERTED WAVEFORMS: The Sweet Sound of Silence
When two waveforms of equal and opposite amplitude meet, the result is a cancellation of both waveforms. Silence. Okay,
I know what you're thinking. "How is that useful in making synthetic sounds?" A certain amount of cancellation can
yield some interesting results.
For the purposes of this article, let's assume you have a sampler at your disposal (wavetable synths, alas, seldom have
the option of inverting waveforms and thus will be excluded). Now suppose you have isolated a sample that can sustain for
a long time. It can either be just a really long sample or a loop. Create a copy of this individual waveform that will play
along with the original. If you play any key, you will basically hear the original sound except very loud. This is because
the copy waveform is reinforcing the amplitude of the original. This is the opposite of what we want for our little experiment.
This is when you need to invert the copied waveform. This means the positive amplitudes will be turned negative and vice
versa. If your sampler doesn't have such a feature, many audio editing programs for computers can perform this task, such
as Syntrillium's Cool Edit or Creative's WaveStudio. Hopefully you have some way to convert or transfer the sounds back and
forth from your computer to your sampler. There are sample-conversion programs for many brands, or if you've got the same
format of digital input/output on both machines you're set. Now, whether you simply found the option on your sampler or you
had to resort to the alternate kinds of trickery and witchcraft described above, you should have an inverted copy of the original
waveform. And after all the fuss I've put you through so far you're probably itching to hear something cool. But before you
discover that the steps thus far only produce total silence, and you swear I will feel your wrath for this, let me just say
we're not quite finished yet.
The last step is modulation. Any difference in pitch, pan, or volume to either or both of the waveforms will undo the
cancellation to various degrees. For example, try detuning one of the waveforms. You should hear sort of a phasing effect
coupled with a slow attack. You could also set an envelope to change the volume of one wave, or pan the waves slowly in opposite
directions (note that the panning method only works in stereo!). Maybe put on a subtle pitch LFO. Any modulations you can
think of that will offset the two waveforms in time, amplitude, or stereo space will work.
Using inverted waveforms can make for great pad sounds, unique phasing-type effects, or breathe life into once sterile
single-cycle loops. As usual, play with those parameters and see what magic you can work.
"Daddy, what's velocity range?"
What is velocity range? A question a child might ask, but not a childish question.
Velocity is a form of MIDI data that measures the force with which the keyboard is hit, and represents this force with
a number from 000 to 127 or 001 to 128, depending on the machine. Velocity range means that a certain waveform on a sampler
or wavetable synth will only sound when velocity from the controlling keyboard falls within a specified range . For example,
suppose a sinewave has a velocity range of 000-064. When the keys are hit hard with velocity values over 064 the sinewave
will not sound, but when the keys are hit softly falling within the range, you will hear the wave.
Different voices or sample layers can occupy various velocity ranges, sounding separately or overlapping. Suppose now
you also have a sawtooth that sounds only with velocities between 65 to 127. Depending on the force with which the keys are
hit you will hear either a sine or a sawtooth. You can assign as many voices to as many ranges as your synth/sampler's architecture
Here's an example of how I applied this with a sampler to good effect. I cracked out my analog synth and setup a simple
resonant sawtooth sound. Setting the low-pass filter cutoff quite low, I took a sample and looped it, then I set the velocity
range from 000-015. After creating a new layer I repeated the process seven times, each time bringing up the filter cutoff
a bit and assigning higher velocity ranges for the layers that didn't overlap the previous ones. I also disabled the effect
of velocity on amplitude on all the layers, so that all the waveforms could be heard loud and clear at all velocities. When
I was finished I had 8 layers, each containing a different looped waveform, and having these velocity ranges: 000-015, 016-031,
032-047, 048-063, 064-079, 080-095, 096-111, and 112-127. The result was a sampled instrument which produced resonant sawtooth
waves with a cutoff point that seemed to increase with higher velocities. When played it has that "percolating"
effect you hear in a lot of techno music, and sounds so sweet when you run it through delay!
I also used the procedure above for an istrument where the velocity triggered samples of an FM sound with different modulation
indices instead of filter cutoff points.
Now that you've seen a few examples of how velocity ranges can be applied, you're free to imagine all sorts of velocity-sensitive
instruments. And they don't have to be the memory-conserving, single-cycle loop-based sounds mentioned above. You can use
more elaborate waveforms in your creation, be it purely synthetic or a realistic emulation, limited only by your sample RAM
A Beginner's Guide to FM Synthesis
Ever played an FM synth but have been too intimidated by all the esoteric terms and parameters to program your own FM
sounds? Who hasn't? For years I would tinker with my Yamaha PSS-680, but that board really doesn't have the extensive parameters
of synths like the DX series and other, more sophisticated, synths. It wasn't until Gary loaned me his DX-100 that I finally
understood the basics of the standard Yamaha-style FM synthesis architecture (what other style of hardware FM synthesis is
there?). Mind you, I'm obviously not John Chowning, but I think I've learned enough to help out anyone out there who might
be trying to figure out how to get into creating their own FM sounds, but you're still going to need some basic knowledge
of general synth terminologies (q.v. my article in Nightwaves issue 4, A Beginner's Glossary of Synthesis Terminologies).
As you may know, FM synthesis relies on one oscillator (the modulator) modulating the frequency of another (the carrier).
What might throw some people off is that in Yamaha-style FM, oscillators are referred to as operators. Okay, no problem...
now you want to establish how your particular synth displays which operators are active and which are affected by the parameters
you will be fiddling with. For the DX- 100, there is a sequence of four digits on some pages to show which operators are active.
The digits are either 1 for active, or 0 for inactive. The first digit will represent the first operator, the second represents
the second operator, etc. For most parameters you should be able to use a certain button (possibly called operator select
or something similar) to see the settings for that same parameter for each of the operators. The DX follows the parameter
value with "1 OP", "2 OP", '3 OP", or "4 OP" which indicates what operator is currently
selected for parameter editing.
Another of the cryptic things about Yamaha's FM synths is the various configurations to choose from. These are often graphically
depicted on the synth itself for easy reference, but it doesn't do a lick of good if you don't know what it means. Here's
how you can decipher these: choose one of the configurations (often a number will correspond with the graphic depictions)
and then isolate a single operator to play on its own. If you hear a sinewave, then the operator you have selected is a carrier.
Any operators that you cannot hear when you isolate them are modulators, unless you forgot to turn up the volume! As you do
this, take note of where the carriers and modulators are shown in the diagrams for each configuration. This way you will be
able to understand the configuration just by looking at the diagram and can pick the desired one for your patch. One last
thing about these diagrams is an operator depicted with a line going out of, and back into, itself. This operator can utilize
feedback, that is to say that it can be set to modulate itself to varying degrees. It is with this operator that sawtooth
tones can be attained if you have the feedback and frequency ratio settings right.
So you've picked a configuration, now what? Well, now it would help to undestand the many parameters that will affect
your FM sound. There are amplitude values that change the static volume of each operator. Take note that the volume of the
modulators will have a dramatic effect on the carrier's timbre. This is called the modulation index.
Next is the frequency ratio. This is a value that represents the frequency of the operator relative to the default value
(usually 1). So a ratio of .5 means the frequency is half that of an operator with a ratio of 1, and a quarter of that of
an operator with a ratio of 2. Everytime the ratio is doubled, you move up an octave. In the case of the DX series there are
a variety of preset ratios which the folks at Yamaha no doubt have determined to be most suitable for making musical sounds.
This may seem limiting if you've used other hardware or software synths, and wish to tweak the modulators to xxx.xxxx hertz
like in Visual Orangator, but you've got to work with what you've got. Try different combinations of carrier/modulator frequency
ratios until something strikes your fancy. If they all sound harsh, try changing the modulation index, or just read on...
Using the synth's amplitude envelopes you make the overall volume and/or the modulation indices dynamic. This is where
the real fun of making FM synth sounds begins. You can make a sound have a loud, harsh attack and then fade out to nothing.
For this sort of thing you want the decay of the modulator to be quicker than that of the carrier. Or you could opt for an
eerie pad sound that starts with gentle sinewave tones slowly being complexified by a modulator that increase in amplitude
with the attack. These are just two examples of what the envelope section offers. Like any good sound designer (not that I
qualify as such) EXPERIMENT!
You may also be able to assign an LFO to the amplitude and/or frequency of each operator. You can choose the type of waveform
as well as how much the pitch or volume of the operator will be affected by it, adding even more comlexity and life to your
To top it all off, many FM boards have additional parameters to allow modulation via velocity or breath controllers. While
not many people are likely to use or even have heard of the latter, the velocity parameters can make the sound even more responsive
if your Yamaha keyboard is velocity sensitive, or if it's being controlled through MIDI by one that is. For this reason alone
I hope to get my hands on a used DX someday so that I might make shiny FM patches whose modulation indices are radically changed
depending on how hard I hit the keys of the controller board.
That's all I can think of considering I don't have Gary's DX-100 sitting in front of me right now. I think I hit the important
aspects of FM, though it may still seem a little esoteric until you get your hands into it and hear the results of the theory.
I discovered that once you get past the obstacle of understanding the under-appreciated, non- subtractive, seemingly alien
FM architecture, designing sounds for it will become as natural as with any other popular kind of synthesis. I hope that I've
helped make that obstacle a little less daunting.
A BEGINNER'S GLOSSARY OF SYNTHESIS TERMINOLOGIES
After having written my article on sample start modulation for issue one, it was suggested to me that I should have explained
all the terms for the benefit of the uninitiated. I considered this, but concluded that it would have weighed down the article,
and the constant digression into such explanations would have added further confusion to it. It would have to be assumed that
my readers had a basic knowledge of synthesis for the piece to be quick and efficient. But the initial suggestion warranted
an article of its own, and this is it. I will attempt to shed light on many of the most common technical terms used in synthesis
today, so that the beginner may have some grasp on the concepts that will no doubt arise throughout the lifespan of this publication.
You'll have to do a lot of jumping from one term to another and back again, so if you don't understand a word or two, look
through the list and see if they are defined.
808 - from Roland's TR-808 drum machine. Often used to refer to the characteristic synthetic drums sounds produced by
Additive - the method of synthesis where numerous sine waves are added to a fundamental frequency. Theoretically any sound
can be recreated using additive synthesis, but the sheer number of partials in a complex sound require tremendous computational
power. The most familiar use of simple additive synthesis is in Hammond organs and the like.
ADSR - abbreviation for ATTACK DECAY SUSTAIN RELEASE. The prototypical envelope invented by Vladimir Ussachevsky for early
Aftertouch - see Pressure.
Aliasing - in digital audio, the distortion that occurs when the frequencies of the source sound exceed the Nyquist frequency.
Amplitude - the extent or loudness of sound at any given time. Amplitude can be positive or negative.
Analog or Analogue - pre-digital method of synthesis that utilizes voltages to produce and process sound.
Analog Modelling - digital synthesis method designed to emulate analog synthesis.
Architecture - the setup and interaction of sound producing and processing components that dictates how sounds are synthesized
on a given machine or piece of software.
Arpeggiator - a device which produces arpeggios at the touch of a key.
Attack - the initial stage of a sound. A fast or strong attack indicates immediacy, as in a loud burst of sound, while
a slow or weak attack makes for a gradual increase, as in a crescendo or swelling.
Band-pass filter - a filter which only allows a defined spectrum of frequencies to pass.
Bit Resolution - the dynamic range possible in a digital audio format. The better the resolution, the more faithful the
recording. Each bit rating is double the resolution of the rating immediately below it (8-bit = 2x7-bit)
Cancellation - when a positive and a negative amplitude cancel each other out.
Clipping - the distortion which occurs when the source sound exceeds the dynamic threshold of a digital recording.
Controller - either 1. a hardware device such as a keyboard used to control a synthesis device, 2. a component of a larger
device used to control a specific aspect of the sounds, such as a mod wheel, or 3. a type of information sent by such devices
or sequencers (e.g. velocity, volume, etc...).
Cross-fade - when one sound is faded out while another is faded in simultaneously. The intent is usually to create a seamless
CV - abbr.: Control Voltage. Pretty self-explanatory. Control voltage is used to control some aspect of synthesis, such
as pitch and filter cutoff on analog synths.
CV pedal - a control voltage pedal most often used to control volume, but can often be used to modulate other things.
Cycle - the smallest pattern within a waveform in which the amplitude starts at zero, travels through positive and negative
values, and then returns to zero.
Decay - the stage in which some property of the sound decreases, such as the amplitude of a sound as it dies out.
Digital Synthesis - any method which relies on digital computers to produce sound.
DIN - pre-MIDI input/output standard for syncronizing drum machines and sequencers. Named for the 5-pin-DIN cable used
to connect devices.
Drum Machine - device that produces drum sounds and rhythm patterns.
Duty cycle - in a pulse wave, the ratio of positive amplitude to wavelength expressed by a percentage.
Dynamic Range - the range between the softest and loudest sounds recordable by a medium.
Dynamic Threshold - the maximum amplitude recordable without distortion.
Emulative - synthesis intended to sound like, or emulate, a pre-existing instrument.
Envelope - a series of time values working in conjuction with modulation values. The ADSR evelope is the most well- known
Filter - to remove certain frequencies from a sound, or a device which performs this function.
Filter cutoff - the point where a filter ceases to affect sound frequencies.
FM - abbr.: Frequency Modulation. Method of synthesis where one oscillator modulates the frequency of another oscillator,
called the carrier. Although technically even a low frequency modulator can be considered frequency modulation, the term FM
is usually only applied when the modulator exceeds 30 Hz or so, and enters the audible range.
Gate - in analog synthesis, an audio signal which indicates when a key on the controller is being pressed and released.
Gate controls the duration of notes played, much like MIDI Note on and Note off messages.
Hertz - a unit of measurement dealing with cycles per second, named after 19th century German physicist Heinrich Hertz.
It can be used to express sound frequency and sample rate. It is subject to the prefixes used in the metric system (megahertz,
High-Pass Filter - a filter which removes low frequencies while allowing higher frequencies to pass.
Hz - see Hertz
LFO - abbr.: Low Frequency Oscillator. A modulator which when applied to pitch produces vibrato, and when applied to amplitude
produces tremolo. LFO's can be any of the basic waveforms (see Sawtooth wave, Sinewave, Square wave, and triangle wave).
Loop - a section of a waveform that repeats itself. Loops are often used in sampling to conserve memory.
Low-Pass Filter - a filter which removes high frequencies while allowing low frequencies to pass.
MIDI - abbr.: Musical Instrument Digital Interface. A standard protocol invented in the 1980's to allow the interaction
and control of multiple synthesis devices.
Mod Wheel - diminutive for Modulation Wheel. A wheel-like controller on a keyboard which can be used in performance to
modulate elements of a synthetic sound. Most commonly used to control LFO depth.
Modular - method of synthesis where numerous modules are connected to produce sound. Modular synthesis has no fixed architecture
and allows significant freedom for sound design. Most modular synthesizers are analog, but recently digital and software synthesizers
have adopted the modular approach.
Modulation - to change any value or property of synthetic sound.
Monophonic - a synth where only one voice can sound at once.
Multitimbral - the ability of a synth to have multiple sounds play and be controlled separately.
Noise - a sound where various frequencies are present at any given time. White noise contains all frequencies, pink noise
has less high frequencies than white, brown noise contains only low frequencies, and red noise is the result of white noise
put through a band pass filter.
Nyquist Frequency - the highest frequency accurately reproduceable by digital means. It is one half of the sample rate
of a digital recording.
Oscillator - a device which produces waveforms.
Pad - a gentle, sustaining sound often with a soft attack usually used to play chords in the background of a piece of
Pan - the position of a sound in stereo space.
Partial - one of the many pure tones (sinewaves) that make up a more complex waveform.
Patch - a synthesized sound, whether it's a single unprocessed oscillator, or many waveforms mixed together and heavily
processed. The term comes from the patch cords used in modular synthesis.
PCM - abbr.: Pulse Code Modulation. Term indicating digital audio.
Physical Modelling - method of synthesis where mathematical algorithms are used to emulate the physical behaviour of acoustic
Polyphonic - a synth where multiple voices can sound at once.
Polyphony - the number of voices a device can play at once.
Preset - a patch or sound included with a synthesizer.
Pressure - the pressure exerted on a key after it is pressed.
Pulse wave - waveform where the transition from positive to negative amplitudes and back is very rapid. See also Square
Pulse width - the length of the positive amplitude in a pulse wave.
Q - the bandwidth of a filter's resonance.
Quantize - the process of moving notes recorded into a sequencer to the closest time intervals specified by the user.
Quantizing is used to correct rhythmic imperfections.
Release - the stage of a sound after a key is released. Sounds with a high release time end less abruptly than those with
Resonance - in filters, a function that reinforces frequencies near the filter-cutoff. Also used to refer to the Q setting.
Resonance is perhaps what analog synthesis is best known for.
Sample - a digital waveform, or a patch made from such waveforms. Also, a single bit of digital audio information.
Sample-and-hold - modulation in fixed time intervals. The modulation can be random, or arpeggio-like.
Sampler - device that allows the user to create their own samples, or import samples created by others for use in composition
and performance. This versatility has made samplers widely popular, and the method of choice for emulative synthesis.
Sample RAM - The amount of Random Access Memory present for storing samples in.
Sample Rate - in digital audio, the rate at which samples of the source sound are taken. Sample rate is most often expressed
in kiloHertz (kHZ). The higher the sample rate, the higher the fidelity of the recording.
Sawtooth wave - basic waveform that contains all the harmonics in ever decreasing amplitude. It has a distinctive "buzzing"
Sidebands - additional frequencies above and below the fundamental produced by FM synthesis.
Sinewave - the purest tone in sound, one of the basic waveforms. It contains no overtones.
Sequencer - device used to record and play back musical events, analogous to notation or piano rolls. Sequencers are used
to control synthesizers to play music automatically to either accompany, or replace, the human performer.
Software Synthesis - any software program dedicated to producing synthetic sound. The term is most often applied to programs
that can produce sound fast enough to be controlled via MIDI for performance or sequencer playback purposes.
Sound Module - a device designed solely to produce sound. It requires connection to a controller device to be played.
Square wave - a waveform with all odd harmonics. Technically it is a pulse wave with a duty cycle of 50%.
Subtractive - method of synthesis where frequencies are removed from a waveform rich in harmonics. Most methods in use
today use subtractive synthesis via filtering.
Sustain - the stage of a sound that remains at a constant value after the decay as long as the key is depressed.
Sys Ex - diminutive for System Exclusive. This is information sent via MIDI intended to be used by only one device, but
to be stored in another.
Theremin - Also known as the Etherovox, instrument invented in the 1920 by Lev Termin (Leon Theremin). The instrument
is controlled by interruption of the energy field around a pitch antenna and an amplitude antenna. The player never touches
the instrument during performance.
Tone Generator - term most often applied to Yamaha's FM sound modules.
Triangle wave - another of the basic waveforms. Contains odd harmonics in decreasing amplitude.
VCA - abbr.: Voltage Controlled Amplitude. The section of an analog synth that controls amplitude.
VCF - abbr.: Voltage Controlled Filter. The filter of an analog synth.
VCO - abbr.: Voltage Controlled Oscillator. The oscillator in an analog synth.
Velocity - the force with with a key is hit. In MIDI instruments, velocity can be expressed as a numerical value from
Velocity sensitive - a keyboard that can record or transmit velocity information.
Voice - general term for either a single waveform or a single oscillator.
Waveform or Wave - the physical or digital shape of a sound.
Wavetable - a collection of samples stored in ROM. Also a synth containing such sounds.
Workstation - a combination of a controller keyboard, a sequencer, and a synthesizer. Many workstations include onboard
Zero Crossing - point in a waveform where amplitude is at zero. Smooth loops should have beginning and end points at zero