Hi guys and welcome to the last episode of the mini-serie dedicated to “making sounds” using the synthesis engine of the Novation Mininova. In the first episode we talked about making a synth lead similar to the ones used by the famous greek composer Vangelis, while in the second episode we tried to program a punchy synth bass.

Now, it’s time to “close the circle” trying to program a pad timbre that leverages on the vocoder of the Mininova, one of the features of this small synth, in my opinion, that is worth its price.

First of all, let’s make a small review on what a vocoder is... I think it’s necessary to fully analize and understand how the patch is built.

A vocoder is an electronic circuit (or a software) that combines two signals, a carrier and a modulator in such a way that the signal produced has got the harmonic content of the modulator and the tuning and the timbral characteristics of the carrier.

In other words and from a more detailed point of view, the modulator signal is filtered from n band pass filters and the result of each filter is sent in input to an envelope follower, a circuit that is able to produce a control signal from and audio one. This phase is named the analisys phase of the vocoder.

The control signals produced by the n envelope followers are used to control the output volume of n band pass filters that filter the carrier signal. Take a look at the following scheme.

The modulator and the carrier could be whatever signals we like, even if usually the modulator is the voice of the musician captured using a microphone and the carrier is a synthesized timbre (for example a synth lead or a synth bass or a lush pad… ).

The higher is n, the more accurate is the vocoder in reconstructing the modulator signal, but a musician may not be interested in reconstructing his voice, but in producing musical timbres in a more creative way.

The vocoder on the Mininova offers 12 bands for the analysis phase and 12 bands for the synthesis phase. For further details about how the Mininova vocoder works please refer to the manual of the instrument. 

If you would like to hear something, take a look at this video, in which Teddy Riley (Michael Jackson) shows what using a Vocoder means.

Let’s talk about our patch: the Mininova offers two kind of modulators to control the vocoding process: a signal that comes from the microphone (for example the gooseneck microphone bundled with the instrument) and a signal that comes from the EXT INPUT on the rear panel of the synth.

What we want to do is to create a lush pad using the waveforms, the filters, the modulations and the effects on the Mininova and to modulate it using an audio signal coming from the EXT INPUT, in order to try to produce a complex and evolving timbre.

Let’s start describing how the carrier patch is built, taking a look at the AU Mininova editor.

OSCILLATORS

What we wanted was a warm and lush pad evolving over the time, so we chose rich waveforms for all the oscillators. In detail:

1. Oscillator 1 is set to produce a SAW wave;
2. Oscillator 2 is set to produce a WAVETABLE waveform (we chose the wavetable 4... it’s a matter of taste);
3. Oscillator 3 is set to a PWM waveform.

As you can imagine, we chose these waveforms in order to modulate some of their features, but let’s proceed step by step.

Regarding the amplitude envelope, we adopted the settings that are typically used when creating a pad sound: slow attack, slow release and maximum sustain.

No portamento, no velocity for now (for simplicity), poly mode.

FILTERS

Again it’s a matter of taste and it also depends of what kind of timbre you want to reach. Generally, when programming a pad a good choice is 12db/oct filters in order to process the signal more gently. In this case we chose two filters in serie, a LP 12db and a HP 12 db, this last one to smooth the lower frequencies a bit.

I also chose to modulate the LP filter frequency a little bit with the filter envelope in order to create a small sweep effect: slow attack, medium decay, medium sustain and slow release.

EFFECTS

A classic configuration, nothing more to say: the EQ to add more loudness, the chorus to enrich the sound and the Reverb 1 and Delay 1 (a little bit) to add more spatiality.

VOCODER

The most interesting part and… where the magic happens!

We have to choose a modulator signal remember? Well, for this timbre we chose not to use the microphone and the musician’s voice but a sample loop sent to the EXT IN input of the Mininova. That’s because what we want to do is to have a continuous timbre that leverages on the vocoder to assume a unique and evolving character.

The sample loop used is a one from the Logic pro X library, precisely an african percussion loop named “African Ghana Kit 08”, take a listen to it.

https://soundcloud.com/antonio-antetomaso/africanpercussions

Sounds good, doesn’t it? Yes but how can we send it to the external input of the Mininova?

Elementary, my dear Watson... using the iPad and a software that can play in loop and that can variate the tempo of the loop without altering the pitch. What about Amazing Slow Downer?

What we did is:

Bounce the audio loop from Logic pro X, in order to create a mp3 file (or a wav one as you prefer);

Connect the iPad to the MAC;

Transfer the loop to Amazing Slow Downer via iTunes;

Connect the iPad to the Mininova using a simple audio cable, from the iPad phones to the Mininova EXT IN.

Obviously you may use whatever signal, whatever tool, whatever mechanism you prefer to send your audio signal to the Mininova.

Let’s take a look to the vocoder section of the AU editor, now.

For the pad we’re programming we chose to use this approach:

1. to hear the carrier signal also when the modulator is not present;
2. to not hear the modulator signal;
3. to introduce a little bit of resonance for the band bass filters of the synthesis section;
4. to increase the decay of the closing phase of the filters;

 Again... it’s a matter of taste.

 Oops... I was just forgettin’.....remember to turn the Vocoder ON!!

MODULATION

Last but not least the modulation matrix. We chose to use three LFOs to modulate respectively the pitch of the saw wave a little bit, the index of the wave table of the second oscillator and the pulse width of the third oscillator.

We also chose to modulate the Vocoder shift using the LFO1 and to control the modulation amount with the modulation wheel, and to use the "Animate 1" and "Animate 2" buttons to increase and decrease the spread of the vocoder. "Shift" and "Spread" are clarified in the following schemas:

Can’t wait to hear the result? 

Here is a small demo of the timbre: 

https://soundcloud.com/antonio-antetomaso/vocoderlushpad

As you can see the vocoder is a very powerful "toy"... it’s up to you to not curb your imagination and to explore continuously.

 And, of course, have fun with your music.

 Ciao!