The Creation of an Artist

Online guides for Mixing, Mastering, and Leveling

2008-06-19T03:40:47Z

Mixdowns for Beginners:
http://tarekith.com/assets/mixdowns.html

Mastering for Beginners:
http://tarekith.com/assets/mastering.html

Leveling and Metering:
http://tarekith.com/assets/Leveling.html

MIDI & Digital Audio Music Sequencer Techniques

2008-05-20T22:36:02Z

Music technology has finally gotten to the point where almost anything sonically imaginable can be achieved. Audio can be recorded, chopped into pieces, and then rearranged into something completely different - all with a few clicks of a computer mouse. Whole environments can be simulated so that while it sounds like your singing on stage in a huge concert hall, you're actually standing in the middle of your bedroom studio. Complete professional-quality songs can be recorded, produced, mixed, and mastered using a single standard computer system with MIDI/ digital audio sequencing software.

Of course, just because you can imagine something doesn't mean you know how to accomplish it. Today's digital audio sequencers pack so much power and contain feature upon feature, that it's easy to stay comfortable and just stick with the basics, especially when you're facing deadlines and don't have the time to experiment.

We're going to take a look at some sequencing techniques that you can use in your day-to-day digital audio dealings. We'll cover a number of generic techniques that will work with any sequencing software you may have. I'm going to assume that you already know the ins-and-outs of MIDI and digital audio. Ready? Set? Let's go...

EFFECTS WITHOUT EFFECTS
The real-time effects built into many sequencers aren't the only way to add excitement to your MIDI and digital audio tracks. With a few applications of the copy, paste, and pitch shift commands, you can easily simulate a number of different effects including delay, flange, and chorus. This can free up some of your computer's precious processing power for handling the more complex effects like compression and reverb.

Digital delay. This technique actually covers a number of different effects, and can be applied to both MIDI and audio tracks. Simply copy the MIDI or audio clip that you want to process, and paste it to a new track. Then slide the copied clip forward in time to create a delay. Depending on how much of a time offset you use, different delay- related effects can be achieved. Slide the clip between 5 and 10 milliseconds and you get a thickening effect. Slide the clip between 10 and 20 milliseconds and the thickening turns into doubling. Anything above that amount and you start creating discrete echoes.

If you want to create a delay that is synchronized in time with the music, just move the copied clip ahead by snapping it to a note value such as a sixteenth. To make things more realistic, make a few clip copies and slide each one a sixteenth note apart. Then lower the volume of each successive echo so that the effect fades over time. As an example, for three echoes, lower the volume of the first to 75%, the second to 50%, and the third to 25% of the original. You can even get a little crazy by sliding each copy to a different uneven time offset, and maybe give them different pan positions too. You can't get that kind of precise flexibility with a real-time effect.

Flange. This effect can be applied to both MIDI and digital audio tracks but they require slightly different procedures. As with delay, simply copy your clip to a new track. From here, you can easily produce a static flange effect by moving the copy forward in time from 1 to 5 milliseconds. While this creates an interesting sound, it doesn't have that authentic analog sweeping that we all love and cherish. To achieve that, we need to use a little pitch shifting.

For audio, instead of moving the clip copy, just shift its pitch anywhere from -12 to +12 cents. This will make the copy longer or shorter by a minute amount, causing it to drift out of sync with the original. Of course, depending on how long the clip is, eventually there will be so much of a delay that the flanging will turn into doubling. To get around that, just shift the pitch of small segments of the clip, alternating the direction of the shift with each segment. For example, shift the first two seconds of the clip by -9 cents, the next two seconds by +9 cents, and so on. This is also how you can control the rise and fall of the sweeping characteristic.

For MIDI, the procedure is similar except you need to apply pitch wheel controller changes to the clip copy. Just draw in some pitch controller changes over the course of the clip that vary by rising above and falling below the zero axis. I found it best to stay within the +600 to -600 bend range because any changes larger than that start sounding like detuning rather than flanging. To apply precise changes, many sequencers will allow you to insert a series of controllers that change evenly from a start value to an end value over a set amount of time. This will give you more precise sounding effects but you may prefer the more random fluctuations you can get from just drawing the controller changes in by hand. Either way, the effect is not quite as authentic as with audio. Many times it sounds more like chorusing than flanging.

Chorus. You create audio chorusing in almost the same way as flanging except you need to stretch the pitch, rather than shift it - meaning you need to change the pitch of the audio clip without changing its length. Most programs have this capability. To apply chorusing to an audio clip, simply copy the clip to a new track and stretch its pitch, plus or minus 9 to 12 cents. The more you stretch it, the deeper the effect. You can also use this technique to create a pseudo-stereo effect from mono parts by simply panning the original clip and clip copy to different locations. The more pan, the wider the stereo image.

If you really want to go wild, you can create something I like to call the Super-Combo Chorus Effect. This time, instead of creating just one clip copy, make 3 or 4 or more. Stretch the pitch of each copy using slightly different values from the rest. Now slide each copy in time using the delay techniques described earlier with slightly different values. For the final touch, evenly pan each copy throughout the stereo field. You can also give each copy a different volume level for more subtlety. When you're finished, hit play to experience one very cool chorus simulation.

EFFECTING THE EFFECTS
When destructively applying plug-in effects to digital audio, many sequencers will let you either replace the original material or leave the original material intact and create a new track (or set of tracks in the case of stereo) for the new effected material. If you adjust the levels of the effect module so that the dry mix level is 0% and the wet mix level is 100%, your new track(s) will contain the effect output minus the original signal. Why would you want to do this? Because it gives you some very interesting possibilities.

For instance, you can now control your track effects in a variety of ways. Using volume controllers you can bring the effects track(s) in and out to add an artistic flair to the mix. You can also use panning to move the effected signal around the stereo field while the original signal either remains stationary or moves around as well but independently. Even more possibilities arise when you consider that you can add effects to the effects track(s). How about applying different EQ to the original and effected tracks? If your effected tracks contain reverb, how about applying another reverb effect on top of that for some very far out spatial displacement?

And if you happen to have multiple soundcards or multiple outputs, you can assign your effects track(s) to their own outputs. This way you can even use your outboard modules to add effects to the already effected track(s). Experimentation is the key here.

QUANTIZING AUDIO
You've probably heard of the term "Groove Quantizing" or something similar, where a sequencer uses a pre-defined MIDI pattern that contains data in a specific rhythmic style and applies it to recorded MIDI data so that it conforms to the same rhythm. This feature is a great way to breathe new life into a tune or even give it a different sense of feel.

Well, in case you didn't know it, you can also use "Groove Quantizing" on audio tracks. You just need to do one small preparatory step. You need to break down the audio track (or audio clip) into small pieces or clips. Some sequencers will have an automatic feature for this. If yours doesn't, you can try exporting your track to an audio editing program like Sound Forge. Using Sound Forges' Auto Region and Extract Regions tools, you can easily break down a large audio file into smaller ones that contain a quantizable musical unit such as one beat of data.

When you import the small audio files back into your sequencer, each one will have its own start time, just like a MIDI event. This lets you easily quantize the playback of the audio segments, and you also don't get the weird anomalies that can arise from trying to stretch the audio. This technique works especially great with percussion clips but don't rule out instrumental or even vocal clips. Try turning a normal vocal track into a cool rhythmic scat. It's a lot of fun!

NEW SOUNDS WITH NRPNs
In addition to responding to the usual MIDI controller messages such as pan, volume, and pitch bend, most synthesizer modules have a number of "hidden" parameters that can be of great use in adding expression to your tunes. The way to get to these parameters is through the use of Non-Registered Parameter Numbers (NRPNs). As an example, let's take a look at the Roland Sound Canvas. This modest module responds to no less than 13 different NRPNs (see Table 1) that allow you to control things like the attack, decay, and release of a patch's envelope, as well as the cutoff frequency and resonance. As a matter of fact, by manipulating these parameters you can create brand new timbres based on the existing sound set, which is otherwise uneditable.

Table 1: NRPN's for the Roland Sound Canvas
Param. Control 98 Control 99 Control 6
Vibrato Rate 8 1 14-114
Vibrato Depth 9 1 14-114
Vibrato Delay 10 1 14-114
Cutoff Frequency 32 1 14-114
Resonance 33 1 14-114
Attack Time 99 1 14-114
Decay Time 100 1 14-114
Release Time 102 1 14-114
Drum Pitch Drum#0-127 24 0-127
Drum TVA Drum#0-127 26 0-127
Drum Pan Drum#0-127 28 0-127
Drum Reverb Drum#0-127 29 0-127
Drum Chorus Drum#0-127 30 0-127

For instance, let's say I wanted to change my basic piano track into something with more of a string feeling but keeping the piano timbre. I would open the event list for that track and insert nine new controller messages (see Table 2). The first three messages would set a new envelope attack, the next three would set the decay, and the last three would set the release. Controllers 98 (Non- Registered Parameter LSB) and 99 (Non-Registered Parameter MSB) are used to set the type of parameter to be changed (in this case envelope attack, decay, and release), and controller 6 (Data Entry MSB) is used to set the value of each selected parameter. All of the settings for each of these controllers depend on what MIDI device you're using them with. Have a look in your synthesizer manual and you might be surprised just how much control you have over that little black box.

Table 2: NRPN Example
Message 1 - Control: 98 Value: 99
Message 2 - Control: 99 Value: 1
Message 3 - Control: 6 Value: 70
Message 4 - Control: 98 Value: 100
Message 5 - Control: 99 Value: 1
Message 6 - Control: 6 Value: 100
Message 7 - Control: 98 Value: 101
Message 8 - Control: 99 Value: 1
Message 9 - Control: 6 Value: 70

A couple things to keep in mind when using NRPNs - send any patch changes down the wire beforehand otherwise you may end up with a different sound than what you were aiming for - although this could result in a pleasant surprise. The other thing to remember is that controller 6 is dynamic, meaning it changes the value of whatever was the last parameter that was set with controllers 98 and 99. In the above example, if later on in the track I sent another controller 6 message, this would change the envelope release since that was the last set parameter. In order to change either the attack or decay, I'd have to resend the appropriate values for controllers 98 and 99.

NRPNs IN THE MIX
Another exciting aspect about NRPNs is that they can be sent in real-time, just like any other controller messages. What this means to you is that depending on your synthesizer module, you can now dynamically change the characteristics of patches or any other supported parameters and record those changes into your mix. In the case of the Roland Sound Canvas, you could easily add expressiveness to your sounds by varying their cutoff frequencies and resonance. In addition, you can dynamically vary the pan position, volume and pitch of the individual drums in a set. That could make for some very cool percussion parts.

Of course, typing in all these parameters would be a bit tedious. A better way would be to setup a special mixing template for just this sort of task. Most high-end sequencers provide the capability for you to create your own virtual mixing controller. In Steinberg Cubase the feature is called the MIDI Mixer. In Cakewalk Pro Audio and Sonar it's called StudioWare. Everyone has a different name for it but the feature is still the same. If you're lucky, your software will come with a pre-made template for your MIDI instrument. Cakewalk has a Roland GS template for use with a Sound Canvas but it's missing any drum parameter controls.

If I wanted to add individual drum panning to the existing Cakewalk Roland GS template, I would open a new copy of the template into my existing project. I'd then add a new Cluster widget to hold the new set of controls. Then I would add a slider object to represent the drum instrument number. From there, I'd set the necessary properties for the slider including Label (Drum Number), Alias (Drum_Number), Automate in Track (AutoTrack), Range (0-Min, 127-Max), Primary Action (Kind: Controller, Channel: Part, Number: 98, Value: Drum_Number), and Return Action (Kind: Controller, Channel: Part, Number: 99, Value: 28).

The Alias acts as sort of a program variable which is then used in the Value setting of the Primary Action property to tell Cakewalk to use the value of the on-screen slider (0-127 set in the Range property) as the MIDI controller value. In contrast, the Value setting of the Return Action is permanently at 28 because MIDI controller 99 is a constant value in this case. The Label is just an on-screen text name for the slider and the Automate in Track property just tells Cakewalk which track to record the automation data from this slider to during mixdown. In this case, AutoTrack automatically sets this property to whatever the currently selected track may be.

To complete the drum panning controls, I would also need to insert a Knob widget to represent the drum panning value. With this new control set I could now easily select any of the Sound Canvas drum instruments by moving the slider to the appropriate number and then pan the instrument using the knob - recording any changes to a designated track. Of course this whole procedure would be a bit different in another sequencing program but the concept is still the same. Once you learn how to create your own virtual mixer templates, the possibilities are endless.

THE ULTIMATE TEMPLATE
When inspiration hits, you don't want to waste your time fiddling with sequencer setup parameters. You want to be able to start your software and get right to work. If you create a template file that contains everything set just the way you like it, you'll have a much better chance of getting that cool lick down before you forget it. Here's what you need to do to create the ultimate project template...

1. Use the File > New command to create a blank project. Then setup the track display with all of the instruments in your studio. Set the name, input, output, channel, bank, patch, volume, pan, etc. for each track.
2. Go through the rest of the program and set things up exactly the way you like them. That includes window positions, zoom, and even the last tool used. In Cakewalk Pro Audio and Sonar other parameters like timebase, file information and comments, tempo settings, meter and key settings, clock and synchronization information, and more can all be saved.
3. If your software has a built-in System Exclusive librarian, fill it up with all of your favorite Sysex macros, so that you have them readily available. This could be anything from a favorite bank of patches for one of your synthesizer modules or even basic messages like: Roland GS Reset (F0 41 10 42 12 40 00 7F 00 41 F7) and Yamaha XG Reset (F0 43 10 4C 00 00 7E 00 F7). If your software doesn't have a Sysex librarian feature, then just designate a special track for Sysex messages and save each macro as a separate sequence or clip. Be sure to keep that track muted so its data won't be transmitted during playback. When you need to use a certain Sysex macro, just drag-and-drop it to an open track.
4. Taking the Sysex track idea one step further, you can also create special tracks for your favorite MIDI controller macros. A MIDI volume track can hold different sets of volume changes such as fade in and fade out segments for a number of bars. A MIDI pan track can hold different sets of pan changes. Some interesting ones include a left to right sweep, and right to left sweep, and a center to right to left back to center sweep. In addition, you can create tracks for your favorite drum patterns or sequenced melodic patterns as well. And if your sequencer allows you to store MIDI and audio data together in the same file, you can set up tracks containing some of your favorite digital audio samples and loops too. This way you have all the tools you need right at your disposal for quick and easy drag-and-drop use.
5. The final step is to save your file with all of its settings so that when you open it again, everything will be perfect for your next session. If your sequencer supports it, you can also have the template file load automatically every time you load the software. For Steinberg Cubase on the Mac, name the file Autoload. For Steinberg Cubase on the PC, name the file DEF.ALL. And for Cakewalk Pro Audio and Sonar, save the project as a template file called NORMAL.TPL.

FINAL TIP
Today's digital audio sequencers provide you with a lot of power to accomplish your musical goals. Many times you can achieve the same results in a number of different ways. The tips we've covered here are mainly productivity boosters and techniques you might not have otherwise thought about.

One final word of advice is to go out and buy yourself a small binder to use as a studio journal. As you work on different projects, take a few moments to jot down any new techniques you may come up with in the process. It's also a good idea to reference what you read about in publications, so that you can easily go back and find the issue and page number where you initially saw it. Not only will this save you time on future projects, but eventually you'll have a nice collection of information to refer to.

While technology shouldn't govern the way you make your music, it can certainly help you create the songs of your dreams. The more you learn about how to utilize the tools at hand, the easier the process will be.

http://www.digifreq.com/digifreq/article.asp?ID=12

Add More Boom to your Bass with Sound Forge

2008-05-14T02:46:38Z

Recently someone asked me how they could get that really low bass sound that you hear these days in a lot of techno or pop music. You know, it's not quite a bass drum sound, but more like a low thump that really gets your speakers pumping. Well, believe it or not you can create your own sample of this type of sound very easily using Sound Forge. Here's how:

1) Select File>New, and choose 44,100 Hz, 16-bit, mono to create a new window for your sound.
2) Select Tools>Synthesis>Simple to open the Simple Synthesis dialog box.
3) Set the amplitude parameter to 0 dB.
4) Set the Waveform Shape parameter to Sine.
5) Set the Length to 0.100 seconds.
6) Set the Frequency to 50 Hz.
7) Click OK.

Hit the space bar on your computer keyboard to play the sound. Cool, isn't it? It's also very quick in duration, but that's what you need because you'll be using it in conjunction with your bass sound.

Now if you'd like to use the sound in your sampling hardware or software, just save it as a WAV file. Then import the WAV file as a new sample (this procedure varies depending on your sampling hardware or software) and you're ready to start triggering your new sound via MIDI.

If you don't have sampling hardware or software, you can also import the WAV file into your digital audio sequencing software. Let's use Cakewalk for this example...

1) Select the Track to which you want to import the WAV file.
2) Set the Now Time to the beginning of the project.
3) Select Insert>Wave File.
4) Choose the WAV file and click OK.

Now just use this Track to hold your new WAV sound sample, and simply copy and paste the sample into another Track so that it coincides with each note in your bass Track. Now whenever a bass note plays, it will get an extra boost from your boom sample. Just be careful not to play your music too loudly, because you're sure to get complaints from the neighbors!

Propellerhead Reason Subtractor Synth - Using Envelopes

2008-04-18T20:20:49Z

When discussing sound and sound synthesis, the word envelope is used to describe the shape of a sound over time. The Subtractor has three envelopes to play with: the Amp Envelope, the Filter Envelope, and the Modulation Envelope. You may be wondering what I mean by an envelope describing the shape of a sound over time. Imagine striking a large bell with a hammer. Think of the sound of this event happening in real time. At the beginning of the event is the initial strike. In envelope-speak, this is referred to as the attack. After the attack, the sound begins to fade out, or decay. This vocabulary, as you will read below, has been expanded to incorporate more detailed concepts, but you are probably starting to get a feel for where this is headed.

When we want to affect the volume (or amplitude) structure of the sound event over time, we will adjust the Amp Envelope. You may have been thinking in terms of volume or presence of sound as you considered the bell example. When we want to affect the tonal or frequency characteristics of a sound over time, we will be adjusting the Filter Envelope. And, of course, if we want to affect the manner in which modulation is applied to the signal over time, we will use the Modulation Envelope.

ADSR: Four Letters You Cannot Live Without
ADSR—these four letters stand for Attack, Decay, Sustain, and Release. Please say the words to yourself a few times if this concept is new to you. From here on out, you will see these four parameters again and again throughout Reason, and also on just about any analog or emulated analog synthesizer you ever use in the future. With these four parameters, you will sculpt quite a bit of your sound. If you take away nothing else from this book, I hope at least that this section will be clear in your mind for eternity. If you tell someone that you read this book, and that person asks you to show him how ADSR works in Reason, and you are unable to do so, then we will have both brought shame upon me, my ancestors, and all my future generations. No pressure, but with that in mind, please read on.

Amp Envelope
Perhaps the most familiar area in which to play with ADSR is the Amp Envelope (see Figure 1.13). An amplifier, in audio synthesis, makes a signal louder by increasing the amplitude of the signal. If you are looking at a sine wave on an oscilloscope, the amplitude will be the distance between the highest point and lowest point of one cycle of the sine wave. A shorter distance means a quieter signal, while a greater distance (a "taller") sine wave will result in a louder signal.

While the Subtractor's Level control affects the overall volume (or amplification) of your sound, the Amp Envelope controls the shape of how that amplification is applied over time. Will the sound start sharply when you strike a key, or will it fade in slowly? Will it end abruptly when you let go of the key, or fade out slowly? Is a short sound produced, like a drum hit, or is a long, sustained tone produced, like holding down a key on an organ?

Here is how ADSR relates to the Amp Envelope. You can refer to this when considering other ADSR envelopes as well:
* Attack — The amount of time it takes for the amplitude of a sound to climb from zero to its peak level.
* Decay — The amount of time it takes for the amplitude of a sound to fall from its peak level to the level determined by the Sustain parameter, assuming you keep holding down the key(s).
* Sustain — At the end of a note's decay, the Sustain value determines the level at which the amplitude rests as long as the note is being held.
* Release — The amount of time it takes for the level of a sound to drop to zero from whatever level it was when you let go of a note.

The following exercise should make this all quite clear.
1. Start with an empty rack. Create an instance of the reMix mixer by choosing Mixer 14:2 from the Create menu, and then create an instance of Subtractor. In the Subtractor's Patch Browser window, it should say Init Patch.
2. Turn the Freq (frequency) slider on Filter i all the way up. In doing this, you are actually deactivating Filter Why? Because the Filter Type control on Filter r is set for LP 12, which you know stands for 12-decibel Low Pass. It allows low frequencies to pass unaffected, while filtering out high frequencies (any frequencies above the frequency chosen with the Freq slider). So when you turn the Freq slider all the way up, there are no frequencies above that to be filtered. It's wide open.
3. Change the waveform on Oscillator i to a Square wave. This should be slightly less grating than the Sawtooth waveform. It's also fun if you know how to play any classic video game music, such as the Mario Brothers music.

Now that we can hear our naked square wave without any bells and whistles to confuse the issue, we are ready to explore ADSR in the Amp Envelope:
1. By default, the Attack setting on the Amp Envelope is all the way down at 1 (fastest/shortest attack possible). So when you hit a key, you hear sound instantaneously. Please move the Attack slider up to a value of about 69 (a little over halfway). Depress a key on your MIDI keyboard, and you will now hear that the note fades in slowly. Feel free to experiment with different values to get a feel for this.
2. Turn the Attack back down to zero, and also turn Sustain and Release down to zero.
3. Set the Decay to a value of about 5o. Not such a long note anymore! If you turn it down even lower (to any value between zero and 20), the note will be so short as to sound like a percussion instrument. I have mine set at 20 right now, and am amusing myself by playing "Popcorn," the whimsical, pioneering electronic dance mega-hit by Gershon Kingsley. This song was originally played on a Moog synthesizer, by the way. (Google this stuff if you don't know about it!)
4. With your Attack still at zero, and your Decay set at 20, turn up your Sustain level to 5o. Hold down a key. You will hear the sharp attack and the quick decay, but the decay will no longer fall down all the way to silence. It stops and holds at an intermediate level. Now turn up your Sustain all the way. When you hold down a key, the sound stays at its maximum level until you let go. Theoretically, the Decay setting would still allow the level to fall to the value designated by the Sustain slider, but since the Sustain value is set at maximum, there is no place to fall!
5. With Attack still at zero, Decay at 20, and Sustain at maximum, move the Release slider (which should still be at zero right now) up to a value of 6o. Now strike a key and let go. Notice how the note continues to fade out after you release it.
6. Move the Release slider up to maximum. Now hit a note or a chord, and hear it sustain forever (almost)! Before this drives you crazy, turn the Release slider back down. It would eventually fade out after a while, but it takes a long time.

Honestly, in the past I have suffered some confusion regarding this sustain, release, and decay thing. (Attack always seemed pretty straightforward to me.) You may be a quicker learner than I am, but if you could use some further clarification, please try the following exercise, maintaining the settings from the previous exercise.
1. Set Attack and Sustain to zero.
2. Set Decay to 6o and Release to 81.
3. Depress and hold a key until the sound fades completely away; then let go. Even though your Release is set at a value of 81, you should not hear anything after letting go of the key.
4. Strike and let go of a key as quickly as possible. (lust quickly tap it.) If you do it right, you should hear the effect of your Release setting. The note will continue to fade out even though you have let it go.

Steps 3 and 4 work the way they do because the Release setting controls the amount of time it takes for the level of a sound to drop to zero from whatever level it was when you let go of a note. When you tap and release the note, it hasn't had time for the Decay portion of the envelope to finish. The note has not dropped back down to zero before you let go. So after you let go, the level will fall at a rate determined by the Release value. You could also turn the Decay setting all the way down, and turn the Sustain all the way up, and still hear the effect of your Release setting.

Filter Envelope
Now, as we learned a little earlier, it is fun to sweep filter frequencies, and I will certainly attest to the fact that it is fun to twiddle knobs with one's bare hands in order to do so. However, it's also nice just to hit a chord and let something happen while you hold it. The Filter Envelope is the first of several features to be discussed that allows you to build some hands-free dynamic sonic action into your patches. It is an ADSR envelope, which also includes a Filter Envelope Amount knob and a Filter Envelope Invert button.

1. Start with an empty rack, then add reMix and Subtractor. In the Subtractor's Patch Browser window, it should say Init Patch. Please play a few keys on your MIDI keyboard. Notice the percussive attack that is present in the Init Patch.
2. In the Velocity section, turn down F.Env to zero (12 o'clock). You will see the little red light above it turn off. If you strike a few keys now, you will hear the little percussive attack that was there when striking the keys hard has disappeared because velocity (how hard you strike a key) is no longer affecting how much of the Filter Envelope is applied. The Filter Envelope Amt (amount) knob is already at zero, so the Filter Envelope is not being used at the moment.
3. In the Amp Envelope section, turn the Release slider up to 64.
4. Change the filter type of Filter i to LP 24 by clicking the Filter i Type button.
5. Turn the Filter 1 Frequency slider down to a value of 24. If you play some keys on your MIDI keyboard, you will not hear very much because most of the frequencies are being filtered out now.
6. Turn the Filter Envelope Amount knob all the way to the right (to its maximum value of 127). Now play some keys, and you will hear the sharp attack and short decay of the Filter Envelope affecting the frequency of Filter i.
7. Adjust the Filter Envelope so that Attack = 99, Decay = 99, Sustain = zero, and Release = 76.
8. Play and hold a chord on your MIDI keyboard. Now you can do a nice slow filter sweep while keeping both hands on your keyboard!

The next exercise demonstrates the function of the Filter Envelope Invert button. Clicking the Filter Envelope Invert button turns the whole Filter Envelope upside down. For instance, the Decay parameter would normally control how fast the frequency of Filter i is lowered. When you engage the Filter Envelope Invert button, this is reversed, and the frequency of Filter I will actually increase by the same amount at the rate set by the Decay parameter. To hear this in action, please do the following exercise.

1. Start with an empty rack, then add reMix and Subtractor. In the Subtractor's Patch Browser window, it should say lnit Patch. This exercise can get a hair loud, so turn down the Subtractor's Master Level slider to about 6o.
2. In the Velocity section, turn down F.Env to zero (12 o'clock). You will see the little red light above it turn off.
3. Set Filter i so that Freq=2o, Resonance=o, and Type=Notch.
4. Click on the Filter 2 Link button and the Filter 2 On/Off button (which will both light up red).
5. Set Filter 2 Frequency to 58 and Filter 2 Resonance to 89.
6. Set the Filter Envelope so that Attack=o, Decay=63, Sustain=o, and Release=o.
7. Set the Filter Envelope Amount (Ann) knob to 28.
8. Play a few notes, and you will hear the instant attack (Filter i frequency is at its highest point), followed by the decay (Filter i frequency falls at a rate determined by the Filter Envelope Decay slider).
9. Now click on the Filter Envelope Invert button. Play some more, and you will hear that the envelope has indeed been inverted. Now Filter 1 frequency starts at its low point and rises at a rate determined by the Filter Envelope Decay slider.

Mod Envelope
The Mod Envelope is another magical pair of invisible knob-twiddling hands that I have to tell you about. The Mod in Mod Envelope is (of course) short for modulation, and we know that to modulate in this context simply means to change or adjust a characteristic. So there is a change that is going to take place, such as changing the pitch of an oscillator or the frequency of Filter 2. The degree of this change will be determined by the Mod Envelope Amount (Amt) knob. How that change is implemented over time will be determined once again by an ADSR envelope.

The Mod Envelope looks almost exactly the same as the Filter Envelope. Like the Filter Envelope, it has sliders for Attack, Decay, Sustain, and Release. It also has an Amount knob and an Invert button. However, unlike the Filter Envelope, the Mod Envelope has a Destination button. While the Filter Envelope is hardwired to affect Filter i frequency, the Modulation Envelope can be assigned to affect Oscillator i pitch, Oscillator 2 pitch, the mix between Osc i and Osc 2, the amount of frequency modulation (FM), the phase offset of both Osc 1 and Osc2 (simultaneously), and Filter 2 Frequency. Let's give it a spin. You know the drill by now, but here it goes.

1. Start with an empty rack, then add reMix and Subtractor. In the Subtractor's Patch Browser window, it should say Init Patch.
2. Turn the Mod Envelope Amount (Amt) knob up to 12 o'clock. Play some notes on your MIDI keyboard, and you should hear an immediate effect. By default, the Mod Envelope Destination is set for Osc 1, so the Mod Envelope is affecting the pitch of Osc i. Since the Mod Envelope Attack is set for 0, the Mod Envelope affects the pitch of Osc I immediately to a degree determined by the Mod Envelope Amount knob. The short decay allows the pitch of Osc 1 to fall back to normal quickly, almost like an electronic drum sound.
3. Click the Osc 2 On/Off button so that it is lit red, then click the Mod Envelope Destination (Dest) button until the red light next to FM is lit. Play a few notes, and you will hear the Mod Envelope applied to the FM amount.
4. Click on Filter z's On/Off button so it is lit up red. Set the Filter 2 Resonance (Res) slider to 99.
5. Select Filter 2 frequency (Freq 2) as the destination for the Mod Envelope. Play your MIDI keyboard to hear the effect.

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