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Prophet 12 Overview There aren’t a lot of 12-voice polyphonic synths on the market. Given you probably have 10 fingers, there are more than enough voices to go around. This synth features four digital oscillators plus one sub oscillator per voice. That makes 60 oscillators! Two filters (low-pass and high-pass), four envelopes and four LFOs shape the sound while feedback, stereo spread, delay, character, distortion really bring it to life. Here are some highlights from the instrument… The Patches There are 4 banks of 99 factory patches and another set of 4 banks of 99 user-customizable patches. With this many patches, the factory set runs the gamut of all types of sounds. Some are just silly, some are overdone, but many are quite usable and serve as a great reference to programming your own sounds. Quick Tip Many of the factory presets employ the “Stack” feature allowing you to layer 2 sounds together. So, when deconstructing a factory patch, check to see if “Stack” is turned on. If so, turn it off and use the “Edit Layer B” button to toggle between the two layers until your hear the sound you’re interested in. Then proceed to analyze the patch settings. You may find it useful to press the “Show” button near the screen in order to view the patch settings without changing them. FM/AM/Sync and Slop The gang’s all here. Frequency Modulation (FM) and Amplitude Modulation (AM) both add enharmonic content in the form of sidebands. The Prophet 12 has both available at the same time, and FM has two different modes available: linear and exponential. Choose “linear” for the classic FM sound. Get crazy and choose “exponential” when you’re ready to venture out. We’ve covered Oscillator Sync in an earlier episode. On the Prophet 12, you can sync an oscillator to its neighbor. This can create interesting textures when the synced oscillator is tuned higher than the one it is synced to. Automate tuning changes with an LFO or envelope to create vowel-like sounds. Slop is unique to DSI. It basically takes the rock-solid digital oscillators and simulates tuning instability. This makes for less-pristine, natural sounds. Shape Mod One of my favorite parts of the Prophet 12 is the shape mod. It boils down to being able to continuously alter the wave shape of the oscillators by morphing the shapes. Think of it like PWM (pulse width modulation) but for all the wave shapes including those non-traditional waves like “Tines” or “Mellow”. Spend some time morphing shapes to come up with unique textures. But that’s not all On-board arpeggiator, touch sliders, polyphonic aftertouch, unison mode, almost 100 modulation destinations, and on and on make this one of the most feature-complete synths available. Bottom Line This is a winner. One of those “if I only had one synth” candidates. Oh, and Taylor Swift plays one, so it must be great!

Bass Station Overview The Novation Bass Station is a monophonic analog synthesizer with some nice bells and whistles. Don’t let the name limit your opinion on this machine. It works well as a mono lead synth, and it also can operate as part of a polyphonic setup by chaining multiple Bass Stations together. Sound Architecture The Bass Station features 2 oscillators (saw or pulse), a resonant low-pass filter (12 or 24db/octave), 2 ADSR envelopes and an LFO (random, triangle, saw). It can even mix in an external audio source. It can be setup to emulate the famous Roland TB-303 by selecting a single oscillator and using the 12db/octave setting in the filter.

Frequency Modulation Defined FM synthesis is the process of changing the frequency of one oscillator based on some other oscillator. Doing so creates “sidebands” which are extra frequencies above and below the original oscillator’s frequency. At a relatively slow rate, this produces a vibrato effect when the modulation is performed by a sine or triangle wave. When the modulating oscillator is a square wave, the effect is a trill (rapid alternation between two notes). Speeding up the modulation into the audible range is where we find extra frequency bands known as sidebands. Unless the two original oscillators are harmonically related, the sidebands seem to be random (although they are actually mathematically predictable.) With so much harmonically-unrelated content, the resulting tone can sound metallic—similar to ringing a large bell. You’re left to shape the harmonics with filtering or by adding more oscillators to reduce the apparent presence of the harmonics.

Overview MIDI (musical instrument digital interface) was developed to provide standardized communication between synthesizers. Today, it is much more than that and is found in computer, video games, effects processors and more. We’re primarily focusing on how to use it in music production—specifically with synths. History During the late 1970s and early 1980s as synthesizers became more powerful and polyphonic, controlling synths became more and more of a struggle. Traditional methods of using control voltage (CV) and gate signals was particularly problematic due to inconsistent CV requirements among the various manufacturers. Additionally, a single pair of CV/Gate connections could only send one control signal at a time. CV is inherently monophonic. Other control mechanisms had been developed, but these were strictly proprietary to each manufacturer. MIDI solved these problems. In 1983, Dave Smith and Ikutaru Kakehashi demonstrated MIDI control between a Sequential Prophet 600 and a Roland JP6 promoting collaboration among synthesizer manufacturers. Connections MIDI’s original connectors are 5-pin DIN connectors. While other physical connections (USB, Firewire, etc.) are able to carry MIDI data, the original connectors are still widely used. Three different connections are possible: IN, OUT, THRU. Generally, a controller (like a keyboard or sequencer) is connected from its OUT jack to another device’s IN jack. MIDI Thru duplicates the information arriving at a device’s IN jack and passes it back out to some other device. This way several devices can be controlled by a single controller. Numbers MIDI sends its information on 16 channels. Using the connection method mentioned above, the devices connected to a controller can be configured to listen on one or more of these 16 channels and ignore information on others. Maybe a sequencer sends piano information on channel 1 and drum information on channel 10. The piano module and drum module in the chain are then configured accordingly. Messages MIDI organizes information into various message types. While not an exhaustive list, here are some of the most common message types: Note on/Note off messages are accompanied by MIDI note number and a velocity value. Velocity is how hard the note is pressed. Some instruments respond to velocity differences. Some don’t. Most synthesizers which do respond to velocity can be programmed to do something interesting like open the filter more, boost envelope values, etc. Program change messages switch the receiving instrument to a different preset number. Beyond synthesizers, this can be used with effect processors or digital mixers to automate performances. Usually program change messages range from 0-127 or 1-128. Control change (CC) messages are for things like volume, pan, etc. Generally, anything that benefits from a range of values is a candidate for control change. Think of the drawbars on a Hammond organ or the cutoff frequency on an analog synth. Sweeping through these values rather than simply picking a single value creates dynamic and interesting performances. Control change messages are transmitted with an identifier for the type of CC (0-127) and a value (also 0-127). Pitch bend and aftertouch messages are often confused with control change messages. These special message types operate more or less the same but are not transmitted as control changes. Aftertouch describes the amount of pressure put on keyboard keys while a note is sustained and is actually available as either channel aftertouch or polyphonic aftertouch. The first one only sends the pressure value from the single hardest-pressed note while the latter sends pressure values for all notes individually. Incredibly expressive, aftertouch can usually be programmed into your synth patch to respond with something like vibrato, filter changes, LFO speed changes, etc. System exclusive messages (sysex) are well beyond the scope of this article. Sysex can be used to dump single preset data or entire machine setups to be stored as a file on your computer or in your sequencer, etc. Sync MIDI also has provisions to keep everything sync’ed together. Sync messages are not sent on individual channels. All devices receive sync data unless configured to ignore it. Sync options include MIDI Timecode (MTC), MIDI Clock and Song Position Pointer (SPP). When syncing from a computer, it is best to configure your DAW to send either MTC or MIDI Clock and SPP. Transmitting both can cause double notes and hiccups. Computer Options Most audio interfaces offer a set of MIDI IN/OUT connections. This is okay when you only have a couple of devices in your MIDI setup. But, once your collection expands and you need more than 16 channels, look for a MIDI interface with multiple ins and outs. Mark of the Unicorn (MOTU) still has a few of these available. More Info The authority on MIDI is midi.org. Lots of documentation and helpful articles are now available on the official site. Additionally, consult the user guides for your synths. You’ll be surprised how much you can learn from the manuals.

The Atmegatron In the podcast episode, Paul Soulsby describes his Atmegatron products. These are 8-bit digital synthesizers built on the Arduino platform. The Atmegatron hardware consists of a small, desktop module with a unique user interface and wood sides. The knob layout can be daunting at first, but you quickly get the hang of it. It’s A Chameleon The really amazing part of the Atmegatron is its hackability. Soulsby offers an accessory pack which allows you to load new software onto the Atmegatron which can completely change the behavior of the instrument. There are several different official software version available including a polyphonic string synth, a drum machine and an analog-sounding synth based on the ARP Odyssey. Each version can completely re-map the controls on the hardware. So, overlays are available to help you use each different instrument effectively. During the podcast, Paul demonstrated how quick and easy it is to upload different versions. The process only takes 20-30 seconds. Each version has a dramatically different character. And, if you’re the type who can jump in and edit code, you’ll have plenty of fun making your own synth. All of the source code is available on github. If not, there’s plenty of fun to be had with the standard offerings. What We Glossed Over In our discussion, I briefly mentioned the mini-Atmegatron, but we didn’t go into details. This is a DIY-kit for building your own synth. It has a lot of the same features as the full-fledged version of the Atmegatron. The finished kit is an Arduino shield (little circuit board that plugs in to an Arduino). It is a quick build and incredibly affordable—especially if you already have a spare Arduino Uno. Get One Paul was a lot of fun to talk to, and I’m excited to see what he comes up with in the coming months and years. The ongoing development on the platform is a huge benefit to owners of the Atmegatron. I highly recommend picking one up from your favorite synth shop. Links Soulsby Synthesizers Website Soulsby Twitter

What it is The Moog Mother-32 is a semi-modular monophonic analog synthesizer in a eurorack form factor. It can be used as a standalone synth or in conjunction with a larger eurorack modular setup. Sound engine The Mother-32 offers a single voltage controlled oscillator (VCO) which produces pulse and saw waves. One wave shape can be selected at a time, although both are available at the patch points which allows both to be used simultaneously if desired. The sound of the VCO passes through a voltage controlled filter (VCF) which can operate in low-pass or high-pass mode. Familiar cutoff and resonance controls provide shaping controls. The VCF can be modulated by either the envelope generator or the LFO in either positive or negative direction. The simple envelope generator (EG) offers attack time and decay time with switchable sustain (either on or off). The onboard low-frequency oscillator (LFO) can take on either triangle or square shape. Its rate is controlled by a dedicated knob and also offers a patch point for control from some other source. Pre-wired destinations for LFO modulation include VCO frequency (vibrato-like), VCO pulse width (PWM), and VCF cutoff. Glide offers a wide range of portamento from subtle to ridiculous. Triggering sound The final step of the signal path passes through a voltage controlled amplifier (VCA). The VCA can be set to “on” which enables an always-on “drone” mode. Or, it can be set to be triggered with the envelope. Either way, the 1-octave on-board keyboard can be set to control which musical note is generated. The range of the single octave is set with up/down buttons and results in a full 8-octave on-board control. You won’t use these push-buttons for complex soloing, but they’re handy for trying out sounds. The keyboard is also used to enter notes into the on-board step sequencer. Each step can have its own duration, accent (on/off) and glide amount. The step sequencer has advanced features for swing and ratcheting as well. Finally, notes can be triggered from an external MIDI controller connected to the MIDI input on the front of the Mother-32. Patching Moog includes 5 small patch cables to get you started connecting any of the 32 patch points. Ins and Outs are clearly labeled making it easy for a beginner like me to experiment. The user manual includes example patches and a complete explanation of each connection—again, making it easy for beginners. Summary Get one. Now.

What It Is The Roland RS-09 is a vintage organ/string synthesizer. Combining organ and string sounds together makes it really handy—although you can choose to play only organ or only strings. And the inclusion of analog chorus really helps fatten up the sound. Vibrato (LFO) The vibrato section of the synth is really an LFO permanently set to control the pitch of the outputs from both the organ and string section of the synth. When only playing the organ section, the vibrato adds interest similar to a rotary speaker. (Although not nearly as exciting as the mighty Leslie speaker.) When playing the string section, vibrato re-creates the rapidly changing pitch a string player provides. Organ While you probably won’t buy the RS-09 for its organ sounds, the organ supports the string section by rounding out the overall sound when mixed together. If you’re used to the drawbars of a Hammond organ, the footage sliders will feel instantly comfortable. Organ I and Organ II buttons can be enabled individually or together. Organ II is a higher-octave, brighter sound from Organ I. The ensemble button within the organ controls enables chorus on just the organ. Strings This is where the RS-09 really shines. Two separate ranges of strings can be enabled together or separately. Unlike the organ section, the strings can be set to swell in gradually by using its dedicated attack control. When combined with the organ, a gradual attack on the strings creates a tone that evolves slowly and naturally. The strings also have a control to enable ensemble, and the combination of the strings with the ensemble (chorus) is really the sound you’re looking for from a string synth. Big, fat and synthy. Decay and Ensemble (chorus) Next to the string section is a decay control which controls both the organ and strings. Setting this all the way up makes for a very long sustained sound. The ensemble section has only one control: I or II. Ensemble one is more of an abstract, electronic chorus while ensemble two is a natural, smoother chorus. As mentioned, the organ and string sections have separate controls to enable the ensemble. As a bonus, the RS-09 includes an external input jack. A signal brought in here is routed through the chorus. Do you need it? Of course you do ;) If you’re looking for vintage synth strings, the RS-09 is a contender. If you’re scoring an orchestral soundtrack, don’t expect the RS-09 (or any vintage string synth) to sound like a real string section. It sounds like a synth—with occasional quirky, unpredictable nuances.

Amplitude Modulation Defined Amplitude modulation is the process of changing the volume of one wave according to the pattern of another wave (Volume is used here as a simple way to understand amplitude. The two are not exactly the same in practice.) Changing the volume of a sound results in a tremolo effect when that change happens relatively slowly. When we speed up that change, we no longer perceive a simple change in volume. That periodic change itself becomes an audible pitch. In fact, when two simple sine waves are combined in this way, two audible pitches appear. These pitches are called “sidebands” and their frequencies turn out to be equal to the sum and difference of the two original waves. For example, a sine wave ad 150 Hz modulating another sine wave at 100 Hz produces a sideband at 250 Hz (150 + 100) and another sideband at 50 Hz (150 -100). That’s great, but what does it mean for synthesizing sounds? In the podcast we play a few samples so you can hear the effect. You’ll notice the sound has a very distinct character which may not be appropriate a lot of times. However, when you need something with a little extra abstract flavor, try some amplitude modulation. What’s the difference? Okay, so you’ve seen both terms: amplitude modulation (AM) and ring modulation. Amplitude modulation keeps one of the two original fundamental waves while ring modulation doesn’t. So, ring modulation may sound more hollow and strange. If your synth only has one or the other, you may be able trick it by manually mixing in (or mixing out) the original fundamental. Where to get it Many classic synths offered either amplitude modulation or ring modulation on board. The ARP 2600 and Yamaha CS-80 both offered them, and the Arturia V Collection includes these features. The Ensoniq ESQ-1 offers amplitude modulation, and the Korg microKorg and MS-20 offer ring modulation. These are just a few. If you’re looking for ring modulation outside of the synth itself, take a look at the DOD Gonkulator Ring Modulator effect pedal. But if you’re truly adventurous, try building one yourself. Refer to the Delptronics Ring Modulator as a guide.

Oscillator Sync Defined Oscillator sync simply synchronizes the period of one waveform with that of another. What does that mean? Basically, the synchronized waveform restarts its wave each time some other waveform completes a cycle. The naming may differ on some synthesizers, but typically there is a “master” oscillator (often OSC 1) which controls the cycles of the “slave” oscillator (often OSC 2). In order for oscillator sync to have any kind of audible effect, the slave oscillator must be tuned higher than the master. And, it must not be tuned to octave multiples of the master. Listen to the podcast for examples of what it sounds like. More Study Fred Welsh’s book, Synthesizer Cookbook: Synthesizer Programming, Sound Analysis, and Universal Patch Book, is an excellent reference on using oscillator sync to produce sounds that couldn’t otherwise be achieved. Looking for the ESQ-1 example patch we created near the end of the episode? Here it is: oscillator sync example for Ensoniq ESQ-1.

Overview Casio CZ synthesizers introduced a new type of synthesis called, “Phase Distortion”. While analog purists won’t be impressed, these digital instruments offer a stepping stone from traditional subtractive synthesis to things like FM synthesis. Models differ in size and features, however all CZ synthesizers share the same sound engine. Each sound can be made up of one or two “lines”, each of which have: A DCO (digitally controlled oscillator) with one or two waveforms. A DCW (digitally controlled waveshaper—similar to a filter) A DCA (digitally controlled amplifier) Each of these three blocks has its own dedicated 8-step envelope for powerful control of all aspects of the sound. Beyond that, there’s ring modulation, noise modulation, detune and vibrato. If you’re looking for something a little different from the same-old subtractive synthesizers at a low price point, give the Casio CZ series a try. Resources Virtual CZ patch editor and hardware emulator In-depth info on CZ

Overview The Korg Poly 800 features two Digitally Controlled Oscillators (DCO) each with a dedicated Envelope Generator (EG). These can be mixed with its noise generator and passed through its 24db/octave low-pass filter. The noise and filter can be controlled by a third EG. The pitch of the DCOs and cutoff frequency of the filter can be modulated with a triangle-wave LFO in the “MG” section. Onboard chorus fattens up the sound nicely. That’s a lot of synth considering the prices in 2015. So what are the drawbacks? Frustrations Editing sounds on the Poly 800 is easy, but not as quick as synths with more controls. The entire set of parameters along with their range of values are printed on the top of the instrument. It is almost like having the manual with you at all times. However, to edit any of those parameters, the user must type in the parameter id, then use the up/down buttons to reach the desired value. Again, not difficult, but not quick either. Some of the modifications available add quicker, knob-per-function access to key functions like filter cutoff. Mods are also available to improve the dismal MIDI implementation of the stock Poly 800. The stock instrument does not implement MIDI system exclusive (ie, for patch storage). One drawback that hasn’t been solved by any mods I’ve seen is the non-velocity sensitive keyboard. It can be frustrating trying to perform with dynamics while having the instrument respond with the same volume always. Why You’ll Love It With all of that said, there may be a place for the Poly 800 in your collection. When prices are low enough, grab a Poly 800 if you enjoy drilling holes to add more pots. You’ll be glad it isn’t a more expensive synth if things don’t go quite right. But when it does go well, you’ll have a nice-sounding analog synthesizer to call your own.

Overview The microKORG is a virtual-analog synthesizer and vocoder. It has 37mini keys, several control knobs, an on-board arpeggiator, a complete MIDI implementation, a PC/Mac patch editor. It may just be synth with the longest production record. The Korg website still shows it as a current product, and it looks like it had its 10th anniversary a few years ago. There have been several versions of the microKORG: the XL version, the red and black version, the gold version. I have the original version here, so that’s my reference in the episode. How does it perform? There seem to be a lot of opinions out there about this one. Some say there are better alternatives out there. That may or may not be the case for you. Here’s some of the good and bad… The Good Stuff Wide array of factory presets show off its ability Live performance knobs along the top give you access to tweak the filter cutoff, resonance, envelope attack and release, and tempo (for arpeggios.) Highly capable engine (see explanation of “virtual analog” below) Arpeggiator is quick to access and easy to use. It opens up some dull sounds to being more interesting. I saw Nick Rhodes use it on stage once, so… Compact, portable, can run on batteries Affordable Wood sides! The Less Good Stuff Mini keys can be hard to play, but look at how many more notes your hand spans! Preset editing could be better. The front panel grid makes it easy to find the setting you want to edit, but cryptic display values make it hard to interpret. The wonderfully expressive live-mode knobs don’t align with their corresponding values in edit mode. Vocoder microphone isn’t great, but you can use another microphone or an external audio input instead. Shift functions (MIDI functions, preset initialization, etc.) are only detailed in the manual. Screening those on the front would’ve been handy. Virtual Analog What is meant by Virtual Analog? It sounds like marketing mumbo jumbo, but it actually means something. Virtual Analog is also known as “Analog Modeling” which might be a more accurate description. It is a method of attempting to re-create the sound of analog synthesizers with digital signal processing. Instead of simply sampling analog waveforms, virtual analog (VA) synths are designed to “model” the analog signal path traditionally made up of discrete electronic components. The emulation is primarily done code that is processed by digital microprocessors. Does it work? Well, that’s a hot topic I’m not going to answer. You’ll have to be the judge. You’ll hear plenty of clips from the instrument on the podcast, so have a listen. Beyond Virtual Analog In addition to the analog-modeled waveforms, oscillator 1 offers a set of digital waves. While working with the classic waves (saw, square, etc.) gives you an instant vintage feel, the digital waves are more modern-sounding. Make It Modular Each preset has 4 virtual patch cables. When the microKORG was first released, modular synthesis wasn’t as popular as it is today. The manual positions this feature as being similar to connecting patch cables on their MS-20 semi-modular synth. So, that’s an interesting idea considering the release in the early 2000s. The idea is, you can virtually patch a cable from several sources to modulate several destinations. This is pretty standard practice—offering modulation sources, but I think their approach was pretty forward-thinking at the time. Resources microKORG patches (here on synthlib) Official product page scroll down the page for manuals and software. the microkorg cookbook

Overview The Ensoniq ESQ-1 is a hefty hybrid digital and analog synthesizer with 8 notes of polyphony. During the Yamaha DX-7 dominated 1980s, the ESQ-1 struggled to gain popularity. Today, however, it has seen a surge in popularity but still can be had for a few hundred dollars. Sound Design Each sound can be made up of: Three digital oscillators (choose from 32 waveforms) Three digitally controlled amplifiers (which mix the three oscillators) One low-pass analog filter with resonance per voice There are many modulation points along the way including pitch modulation of the oscillators, volume modulation of the DCAs, filter cutoff and resonance modulation. The modulation of these values can be controlled by: Three LFOs Four ADSR-style Envelopes (envelope 4 is hardwired to the final output DCA) External MIDI controller, Velocity, Keyboard range, Modulation wheel, and more. The ESQ-1 is also capable of producing sounds with Amplitude Modulation between Oscillators 1 and 2. This function is sometimes called a Ring Modulation effect. This produces “sidebands” which give the tone an inharmonic, almost metallic feel. You can easily get lost in the ESQ-1’s sound design features. Fortunately, the manual is very well written. Check the resources below if you need the manual. Sequencer and MIDI But wait, there’s more. The built-in 8 track sequencer is very capable. It is handy for sketching melodies, controlling external MIDI equipment, or even as a manual arpeggiator. Since each of the 8 tracks in the sequencer can have a different sound assigned to it, the ESQ-1 is truly polyphonic. It can play 8 notes of 8 different sounds at the same time. In fact, you can use the sequencer to set up 8 sounds on 8 different MIDI channels then use an external sequencer or DAW to trigger all of those sounds on 8 different MIDI channels at the same time. Resources The most complete ESQ-1 site on the Internet Patch Library

Overview The Omnichord looks like some kind of weird musical Millennium Falcon. Is it a toy or a serious musical instrument? We’ll, I’m sure it has been used as both. Its toy-like appearance means it shows up often at yard sales, goodwill and thrift stores. But those who know find its lo-fi strumming to be serenely soothing. In the podcast episode, we learned how to strum by gliding a finger along the touch-sensitive ribbed strum panel. But first, engage the desired chord by pressing one or more of the chord buttons in the center area. For more details, consult the manual for your corresponding Omnichord. Here are a few: Manuals OM-84 Manual Q-Chord Manual Other References Omnichord Timeline Omnichord Heaven And, as promised in the podcast, here are examples of the Omnichord in use: Jenny Lewis You Are What You Love Depeche Mode Marceline and Ice King, I Remember You So pay attention and see if you can find it out in the wild.

Overview The Roland Juno 6 and Juno 60 are 6-voice analog polyphonic synthesizers. While limited in functionality by today’s standards, these classics present an extremely accessible interface to synthesis newcomers; and they sound fantastic. Both lack MIDI, the Juno 6 lacks patch storage. All this means you won’t be wasting your time with complicated configurations. Just start playing. Resources TAL-U-NO-LX Software emulation of the Juno 6/60 Juno 6 Owner’s Manual Juno 60 Owner’s Manual Juno 60 MIDI retrofit Another Juno 6/60 MIDI retrofit And one more MIDI retrofit Inspiration In the video below, Nick Rhodes uses a Roland Jupiter 8 (I know, not the same thing) in “Save A Prayer”. Notice the use of the bender. The Juno 6/60 have the same bender. Set the bender to control the DCO at about 33% and see if you can mimic the technique. (Skip to 4:30) Tip And, in case you missed it in the podcast, here’s the tip for integrating a Juno 6/60 into a MIDI setup. Use either a MIDI-controlled drum machine or your DAW (Digital Audio Workstation) to send a click track (or use the rimshot output) to the Juno’s arpeggiator control input. The arpeggiator will now be synced up to the controlling device’s clock.

Filters You’ve seen the filter settings on your synth, maybe you’ve tried changing the settings and can hear the difference, but what is going on? What is a filter anyway? Well, the filter on a synthesizer is just like any other kind of filter. An air filter in your car, a water-purifying filter, a spam filter, they all do one thing: remove stuff. So what stuff does a synthesizer’s filter remove? Frequencies. In a previous episode of the podcast we looked at the oscillators that produce frequency-rich tones. But what happens when you have too many frequencies present in your sound? Well, that’s just noise. In fact, that’s the definition of white noise: all frequencies present at equal volumes. Our filter lets us remove frequencies until what’s left is something you can use in your music. The most common filter on synthesizers is the Low Pass Filter or LPF. Listen to the episode to hear how the LPF shapes your sound. (spoiler alert: it removes high frequency content and leaves you with low frequencies.) LFOs Here’s another one of those acronyms you’ve seen on your synth. An LFO is a Low Frequency Oscillator. Since the last episode covered oscillators, you already know that an oscillator generates sounds. Well, the LFO is different in that its frequency is generally so low that you can’t hear it. Instead the waveform is applied to modify something else in your sound. Common LFO modulation approaches include changing the frequency cutoff, the pitch of the tone, volume, etc. Most synths offer a wide range of things you can modulate with your LFO. And, many offer several LFOs that operate independently of each other. Listen to the episode to hear what LFO modulation sounds like in action. To learn more about filters and LFOs, check out this book at Amazon.com: The Synthesizer: A Comprehensive Guide to Understanding, Programming, Playing, and Recording the Ultimate Electronic Music Instrument.

Oscillators Synthesizers offer many different types of oscillators. But what are they? These are the building blocks of the sounds in your synthesizer. In the episode we talk about the different types of waveforms available in many synthesizers. For a more in-depth look, checkout Physics and Music: The Science of Musical Sound. Envelopes The envelope (sometimes called envelope generator or “EG”) describes how the volume of a sound behaves over time. Percussion instruments generally have a fast attack followed by a fast decay and almost no sustain. An organ tone might have an instant attack and infinite sustain. Envelopes on a synthesizer are often described using the acronym ADSR or Attack, Decay, Sustain, Release. In the episode you’ll hear the difference when modifying these settings. To learn more about oscillators and envelopes, check out this book at Amazon.com: The Synthesizer: A Comprehensive Guide to Understanding, Programming, Playing, and Recording the Ultimate Electronic Music Instrument.