How to create a filter envelope? (new to modular synthesis)
  • One of the main reasons I purchased Audulus was to learn a bit more on modular synthesis, though i'm having trouble figuring out how to create a filter envelope... I can make a basic synth with multiple oscillators, a filter and effects, but can't work out a damn filter envelope!

    What I would like is a filter ADSR with an Envelope Amount setting... Any ideas?

    Chris.
  • Hey Chris,

    What you do is hook the ADSR's value output up to a Level node that converts the (0,1) to something in Hz. Set the level node's max value by using the context menu on its knob. I've attached a little patch that demonstrates this :-)

    cheers
    - Taylor
    FilterMod.audulus
    22K
  • Thanks Taylor! I will take a look tonight... :-)
  • How do you modulate the cutoff freq the filter is already set to with an envelope? The suggestion seems to set it directly. Thx.
  • Well you could do that with a little math (use a constant node, and offset with an add node). Though, perhaps the filter cutoff shown in the curve should be combined with the input instead of overridden.
  • Thx. Take a look at how real modulars do it :)
  • I'll often create a little math structure with a mixer and level nodes to blend, bias and invert modulation signals going into the filter (or anything of course).
    Audulus let's you build at a very low level so
    I find when creating synths I have to decide up front if I'm just making a sound or if I'm trying to create a fully programable instrument.
    It's a lot more work to make something fully tweak able but the app is fast to use.
  • Would be nice if it was simple to set it up with a classic synth structure like a moog with the basic building blocks, but it doesn't quite work that way.

    Here's a good reference (for control signals):
    http://moogarchives.com/m904a.htm
  • The problem with simple solutions is that they usually make too many assumptions about what the user wants to do, and make it hard to do things in a different way form the 'usual'. I personally like the slightly lower-level approach of Audulus - it means a little more work up front, but it means that things are more customizable for each user. It's not as low-level as something like MaxMSP (which I love and use regularly), and I think it strikes a good balance between simple (makes most of the choices for you) and customizable (more work up front, and more options for the end user).

    If you want a more 'simple building block' approach, there are many choices out there (Reason and Tassman Studio come to mind). I, personally, am not sure we need another of those, and like having multiple options to choose from.
  • Me too, I found with Reaktor I was always building little custom modules to re-use in my synths, and often do the same in Tassman.
    It is possible to do something similar in Audulus on the Mac by using Sub nodes and pre building modulation and routing solutions but I've never tried it.
    I think your right Skill, better to stay away from preconceived assumptions.
  • Hmm, no. It's not to do with oversimplifying anything. If I connect an envelope to the filter it completely takes over, and that nice little filter curve graphic that you can move around no longer has any effect. The control inputs should modulate, not override.
  • Add your envelope to a constant first before connecting it to the filter. The constant becomes the Fc (cutoff frequency) of the filter which is modulated by the envelope.

    This actually preserves the option to do it either way - either modulate a 'set' frequency or control it directly.
  • Jabberwocker, the UI isn't ideal for the filter. What I think it should do when overridden is animate the little graph and not allow the user to move it with no effect. Its a little confusing.
  • Taylor, that would be a good way to deal with the UI feedback to the user.
  • Ok. How to make envelope filter wich works with audio inputs? I tried to use envelope follower but the value its to small to rise filters frequency.
  • @Tomaszmanderla, put the filter through a Level node with the level's max set to something big. To set the max, use the context menu on the Level's knob. Then you can turn the knob to control the sweep of the cutoff frequency :-)

    cheers
    - Taylor