Sunday, April 17, 2011

Remove Before Flight: the making of a trance track

I've been wanting for a while to take a shot at an electronica track. I wanted to do it as a new challenge to myself -- I've listened to lots of electronica, but have not tried writing any before -- and as a way of putting some rhythm and melody back into my music. I've been doing a lot of atonal experimental stuff lately and I needed to get back in the groove, figuratively and literally. Here is the result, from my Web site.

The Web site writeup describes the who-did-what for this track, but I wanted to go a bit more into the decision-making process here. Remove Before Flight started out as a drum pattern. A very complicated, cluttered drum pattern. I started with a low tom (not a kick; more on that in a moment) hammering a 4/4, and added drum after drum until I had, well, a mess. Then I started taking stuff back out. I kept doing that until I had a recognizable pattern. The snare and cymbal play a bit while the tom keeps the beat pinned down. One thing I quickly recognized about it is that there is no obvious place for the "one" beat. When I put together the place where the first heavy pad sound comes in, I realized that I had started it on the wrong beat! I went with it, and there are several places in the track where "one" gets redefined, although it isn't glaringly obvious.

I had several specific things that I wanted to do with this track: (1) get the Kawai K5m involved; (2) build a modular patch involving the MOTM-510 WaveWarper; (3) experiment with Shepherd tones; and (4) put together an idea that I've had laying around for a while called the "drum console". The first two sounds that come in after the drum pattern starts -- the bass and electric-piano-like chords -- are both out of the K5m. I've done some stuff with the K5m before, but like a lot of people, I always found the additive synthesis method hard to get a feel for. However, after doing the Mississippi Statescape entirely with additive synthesis (albeit using the simpler Minky Starshine plug-in), I felt like I was ready to take another crack at it.

I started with a patch that I had built previously for part of Solar Flare. I tweaked on that, looking for an interesting melody patch, but it turned out to work better as a bass patch. Then I created another patch for the pulsing electric-piano-like sound. I recorded both of these as virtual tracks, so when I did the mixdown I had to put the K5m in multi mode, which I've never used before, and take the two patches out of separate outputs. And by doing that, I discovered something: the K5m is a lot quieter in multi mode! I'm not quite sure why this is; I think the K5m sums all five outputs together when it's in single mode. The K5m is known for being rather noisy; I've done the mod on mine to increase the output levels, but it's always tough to get the gain staging with it set up right. But from now on, whenever I record the K5m, I'm going to use the multi mode even if I'm only using it monotimbrally. (I found out something else interesting: in the multi mode, you can decide how many voices to allocate to each patch! I don't know of any other synth that lets you control the voice allocation in multitimbral operation this way.) Using poly mode 2 chops off the release phase of each note when the next note starts, giving more of a feel of a monosynth without using the 106's notoriously odd-sounding unison mode.

The high-pitched thing that sort of sounds like a pipe organ is from the JD990. Except for at the beginning, this is always layered with a big pad patch from the Matrix-1000. This turned out to be a good combination, with the somewhat shrill patch from the JD990 layered with the bassy and rather muddy Matrix-1000. I created the 990 patch specifically for this; the M1000 patch is one that I've had laying around. There are several things in the M1000 patch that are modulated by aftertouch to produce a somewhat unsettling detuning effect, which you can hear as the "chorus" portions of the track trail off into the quiet parts. It's a great demonstration of the M1000 modulation matrix.

The track actually uses three different bass patches. I started out with the K5m bass in the quiet parts, but I decided it was too up-front. I remember a patch that I had put together on the JD800 to emulate an electric bass. The basic patch is two layers; I had defined it with a third, disabled layer in an attempt to emulate an 8-string bass. That didn't really work out, but playing it way down at the far left end of the keyboard, it made a great near-subsonic bass for the quiet bits of this track. I knew that neither the K5m nor the JD800 basses would work as the sustained bass that I needed for the big choruses, so for that I created a third bass patch using the V-Synth. This patch has the ability to vary the low end harmonic content using the panel performance knobs (and corresponding MIDI CC #'s), which I use at the final chorus part. I mentioned using a low tom instead of a kick in the drum pattern. I did that because I knew I would be using a deep bass patch at some point in the track, and I don't like a kick drum cluttering up the bass spectrum. My observation is that when you do a track like this, you have to make a choice -- either use a deep kick and keep your bass patch in the mid-bass region, or use a deep bass and don't use a kick. Most electronica producers usually do the former, but I think I prefer the latter. (Must be my progressive-rock background coming through...)

I wanted a sequence that would capture the simplicity of a modular driven by an analog sequencer, but I didn't want to actually use an analog sequencer because (1) I didn't want the sequence to be quite that tick-tock, and (2) I don't have an analog sequencer. Having Metro drive the Juno 106 with a repeating pattern turned out to be just the thing. Funny thing about this: The sequence was one of the first things I did after putting together the drum pattern. I started it using a piano-like patch on the 106 as a placeholder, and I kept using that while I worked on other parts of the song. When the track was almost finished, I finally went back to it to create the patch I had intended, but nothing seemed to work quite as well as the piano patch, even though that patch wasn't what I had in mind and wasn't at all right for the track. I finally sort of compromised with myself by creating a patch that sort of sounds like what you'd get if you took a Wurlitzer and ran it through a wave shaper and an octave divider. This got me closer to what I wanted the sequence to sound like, without sounding too retro. The key to this patch was using gobs of the sub-oscillator, which has a different sound than the primary pulse waveform set to 50% duty cycle.

The Discombobulator plays a big part in Remove Before Flight. In the first quiet segment, there are a variety of sound effects produced using FM techniques. At the first of the year, I purchased three MOTM-310 micro VCOs from someone who was breaking up a large modular, with the specific intention of using them for FM patches. I set up a three-operator patch with one VCO modulating the second one, which modulates the third one. The first VCO is operating at a lower frequency and itself being modulated by an LFO. This patch uses triangle waves as the modulating waveforms; I've found that this often produces more interesting results than the sine waves used in the classic Yamaha FM synths. For this patch, no keyboard or other controller was used; I produced a track of about five minutes' worth of various sounds by tweaking the knobs. I recorded the audio in Metro and then chopped the track up into bits, about two minutes' worth of which actually made the final cut.

In the second quiet part, there's a series of atonal melodies. This was done using the MOTM-510 WaveWarper, which is sort of a super-duper ring modulator that takes three audio inputs and performs an analog computation on them. Two of the 310s were set to an interval (minor third, more or less) and sent to the X and W inputs of the 510. The third 310 was set to a lower frequency and modulated slightly by the low-frequency noise output of an MOTM-101. To play this, I used a keyboard interfaced via the MOTM-650 MIDI/CV interface. I configured a group of two channels and set the group to unison mode. An interesting feature of the unison mode is that if you play one note, both channels output that note. However, if you play two notes, the two channels split and each one takes one of the two notes. Each channel was fed to the control input of one of the 310 VCOs. By doing this, I could play the fixed interval that the 310s were tuned to by playing one note, or play another interval by playing two notes. Unlike the FM patch, this was not pre-recorded as an audio track; I recorded it as MIDI and played the track along with the other synths during the virtual mixdown.

The Discombobulator did one other function: That organ-like patch from the JD990 that I mentioned? It went through the Encore frequency shifter. I configured an aux output on the MOTM-650 to respond to mod wheel (MIDI CC #1) and used that control voltage to control the shift amount. The up-shift and down-shift outputs went to two channels of the mixer and were panned left and right for a stereo effect.

I did the Shepherd tones with Csound, as I have described in a previous post. I captured this as an AIFF file directly from Csound's output. This was imported into Metro and processed as described in the previous post.

The drum console is something that I'll say more about in a later post. One of my frustrations with conventional drum machines is that there is no easy way to change the pitch of the drums you select; for example, on the DR-202, you can change the pitch by going into the drum kit and changing it for that drum assignment in that kit, but it requires menu diving and is something you can't do at performance time. I've been wanting a way to play a particular drum sound over a range of pitches, to simulate e.g., roto-toms. So what I did is: I wrote a Csound program that loads a set of eight drum or percussion samples, and maps each one to a range of eight MIDI notes. Depending on the note played, it shifts the sample up or down, over a range of about half an octave. To play it, I use a Monome 40H, which has 64 keys in an 8x8 arrangement. Each row of the Monome corresponds to one sample; as you go from left to right on the row, it plays the sample at higher pitches.

Because the keys of the Monome aren't velocity sensitive, I coded the Csound program to take input from a Korg Nanocontrol to set a "velocity" parameter for each sample. Each of the 1 through 8 sliders on the Nanocontrol maps to one sample. When the slider is full up, the sample plays pretty much unaltered in dynamics. As you move the slider down, the attack time is increased; the volume is decreased, and a bit of low-pass filtering is applied. At low settings this actually produces a rather unrealistic attack sound, but I though it was interesting so I left it that way. Also, the rotary knob that goes with each channel is used by Csound to pan the sample.

I recorded the drum console parts as MIDI data from the Monome and Nanokontrol (which was tricky because I had to use the OSX IAC bus, and anytime you use the IAC bus you have to be very careful that you don't create a MIDI thru loop). So during the virtual mix I had this playing back through the Csound program. I routed the audio to its own output pair on the audio interface and to the mixer, where reverb got added. So, the resulting audio went from the digital domain to analog, and back to digital again. I learned a lot doing all this. It produces some interesting results, especially with the volume and attack manipulations. I want to extend this idea so I have a lot more control over various parameters and modifications of the samples. One other thing I learned is that the Monome isn't ideal as a drum pad controller; the buttons are kind of spongy and they have too much give for good drum pattern playing, in addition to not being velocity sensitive. But I don't know of any drum pad controller on the market that has 64 pads.

For the mixdown process, I had 12 MIDI tracks going on the various instruments, with everything being fed to the Mackie CR1604 mixer (of which I used all but one input channel, and all four of the effects returns). Nearly all of the mixing was pre-automated by setting up MIDI volume and pan commands to the various synths, so that once I had set the initial levels at the mixer, I didn't have to touch the faders during playback. There was a little bit of riding the master levels to avoid too much clipping -- I didn't use any compression. After that had been recorded to two-track in Metro, there were two additional (stereo) tracks that had to be mixed with the main two-track inside the box. One was the FM sounds from the Discombobulator, which had been chopped up from a longer track. The other was the Shepherd tones, which I wanted to keep in the digital domain, and anyway I had not set up the Shepherd program to be MIDI-controllable. That final in-the-box mix produced the track that you hear.

Remove Before Flight is Part I of the Flight Trilogy, all three of which will be electronica of some sort. I'm just starting to think about Part II. It will be called either "Sea of Crises" (a geographic feature on the Moon) or its Latin equivalent, "Mare Crisium". Right now I'm thinking it will be a downtempo piece, but I haven't decided that for sure.

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