Since Folderol is doing some tutorials on Linux installations, i tought it would be nice to give something back.
So, what is my speciality beside making music ? Modular synthesis
I'm used to work with 2 modular machines, both Clavia, the litle micro-modular and his big brother the Nord Modular G2X.
I was wondering today how easy it would be to reconstruct a modular patch in the AlsaModularSynth on linux.
Here we go, let's start with a simple bass patch (simple but good sounding)
First the real hardware modular patch (see the first pic) :
Pretty straightforward, what do we have.
- 2 Oscilators : One main oscilator with a typical saw output and a second one which output a square to give it a bit of grind.
- Output of both ocilators go into a mixer so that we can mix both signals.
So far our soundsource.
Be aware that modular editor automaticaly connect the incomming midi note to the pitch of the oscilator, you don't see this on the picture
Now that we have a soundsource, we want to do something with the sound
We connect the output of the mixer to a low pass filter which has his own ADSR enveloppe that is triggered by the keyboard gate.
The only thing left to do is sending the sound to the outside world. For that we'll use again a ADSR that will control the amplitude of the audio out comming from our filter ans send to the output of the synth.
Quit simple i would say. On the attached picture, the yellow cables are trigger signals from the keyboard, red cables are audio signals and blue cables are enveloppe signals.
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Now let's recreate this patch with the AlsaModularSynth.
1. Start up the synth
2. Since we need some sound, in the jack control panel connect the 2 outs of the alsa synth to your soundcard.
3. If you don't have a hardware keyboard, launch the midi virtual keyboard and connect (again in jack control) the output of midi keyboard to the input of the alsasynth.
We are ready to create some noise
1. First thing we need is the input of the keyboard, this is called a MSV here, right click on the empty surface and choose it to load.
2. In the same way we will load 2 oscilators called VCO here.
3. We connect the MCV to the oscilator so that they now which note they have to play, so we have to connect the freq(uenty) out of the MCV to the freq-in of both vco's.
4. Like in the modular patch, we will send both outputs pf the VCO's to a mixer, right click on the surface and choose mixer 2->1. Now connect the saw output from vco1 and the rectangle output of vco2 to in0 and in1 of the mixer.
4. To make the signal a bit more interested we'll need a filter that modulates the freq of the signal. On my nord patch i used a 24db lowpass filter. The great thing of Linux is that everything is integrated. Which means that the LADSPA plugins are available in all audio programs. One very good filter is the Mvclpf-3 filter which is an emulation of the famous VC filter invented by Moog. We're gonna use this one. In the top menu of the synth choose 'Show LADSPA browser and then choose the Mvclpf filter.
Same as in the nord patch, we will handle the filter by an envelope module, so load another envelope module. This envelope has to be triggered by the keyboard : connect gate out of the mcv to gate in & retrigger of the enveloppe module.
Now we have an enveloppe that will modulate our filter : connect the ENV out to the Exp. FM in of the Mvclpf filter.
5. Last thing we need is controlling the amplitude of the outgoing signal. For this we need a VCA, load a Lin VCA and connect in In0 to the output of the filter. Since we want to control the VCA we will need another ENV component with an envelope, we will connect the out of the ENV to the Gain0 of the VCA. That way the ENV will control the Gain of our amplifier (VCA)
6. As a last step, we send our signal out to the real world, VCA out to PCM out.
And that's it :
As I didn't explain all the settings of the different components, like the form of the envelopes and stuf like that, I've added the patch in the zipfile, you can load it directly in the AlsaModularSynth.
I tried to use the same color cables as in the modular patch
- Yellow are gate & trigger signal
- Green are frequency signals
- Red is audio
- Blue are envelope signals
Just have a look at the different setting and listen how they change the sound
A very simple patch with a rather good sound/
