Parametric EQ
  • Hi there, I'm just seeing if Audulus is the right app for my rig. I'm thinking of using it mainly as an effect processor for guitar, running it through AudioBus.

    The effects/processing I'm hoping Audulus can handle are:
    - eq (parametric)
    - compression/limiting
    - delay/echo(with a long delay time)
    - reverb

    Could Audulus be suitable for what I want? I'm definitely alright with taking time to build/program these effects, if that's how it would need to be done. I know there are EASIER ways to do this with other apps, but so far they're not tweakable/customizable enough.
  • @Lid555, welcome!

    Right now, Audulus has nodes for delay (10 seconds max, currently) and reverb (really just a diffusor, but you can add early reflections and pre-delay using a delay node). For parametric eq, you could build one out of cascaded BiQuad nodes. Might be a bit tricky though. There's also a compressor here on the forum:

    http://forum.audulus.com/discussion/comment/147#Comment_147

    As we keep improving Audulus, it will get easier to build these effects, but they will still be very customizable :)

    cheers
    - Taylor
  • Thanks Taylor, amazing app!

    I'm just discovering Audulus for the first time. The potential is crazy! Reminds me of MaxMSP on desktop, regarding how much can be done with it.

    So I noticed under "In-App Purchases" there was one called "Custom Nodes"... is this a group of custom nodes that have already been created, or the ability to create custom nodes? I'm guessing it's the latter, which would also means "Math Expression Node Upgrade" would be the ability to use math expressions? If this is the case, then I'll have to spend $35 to get to the point where I can put my effects together? If so, I'll have to do more research, to make sure what I want to do is possible.

    What is the "Switch Pack" all about?

    Also, just so I get some kind of sense of things, could you tell me- for the bi-quad node, with the four inputs, how would one go about selecting the particular cut-off/centre frequency and slope, if possible? Is it naturally a band-pass filter or HPF/LPF?
  • Thanks!

    Yes the Custom Nodes upgrade allow you to build your own UIs on the front panels of sub-patches. And yes, the Math Expression Node, does what you think. More info here: http://audulus.com/help/#ExprNode. The Switch Pack consists of the Mux8 and Demux8 nodes.

    Regarding BiQuads, check out this thread: http://forum.audulus.com/discussion/391/biquad-filters-and-eq#Item_1

    The BiQuad can be used for various filters, but there's a bit of math to be done to compute the coefficients.

    Hope that helps!
    - Taylor
  • Thanks for the info Taylor, I've purchased the basic version of Audulus and I find it quite impressive. I'm surprised I hadn't really discovered it sooner, I mean I had seen Audulus on the App Store many times before but had thought it was only for synths.

    Regarding the Math Expression Node, and Custom Nodes- any suggestions for good references sources for learning how to program EQs and compressors this way? I've taken a look at the Compressor example, checked out the module pieces, but it still seems quite strange how it all works. I'll take a look at MaxMSP tutorials... see what I can learn from there... also, I'll try and dig deeper into discussions on this forum.

    Cheers,
    - Brett
  • Hey Brett, good question. I have this book: http://www.amazon.com/DAFX-Digital-Udo-ouml-lzer/dp/0470665998/ref=sr_1_1?ie=UTF8&qid=1410464962&sr=8-1&keywords=digital+audio+effects

    But the examples are in Matlab.

    This is also useful:

    http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt

    Hope that helps! As Audulus matures we'll have more examples of all this stuff :)