Modular Diary · 5 Sep, 2018 · 9:27 AM · Rudiger Meyer

Possibly related…

  1. Modular Diary · 9 Apr, 2018 · 12:56 PM · Rudiger Meyer

    While taking a look at the difference between the Epoch Modular TwinPeak filter and the one that Rob Hordijk uses in his own system, I got curious about his Dual Fader module. At first I thought that it might not be all that relevant in the Audulus context, but the closer I looked, the more compelling I began to find it.

    The NOVARS Research Centre has fortunately posted an extensive series of Hordijk tutorials (presented by the man himself) and I found it very useful to take a look at the two videos (#12 and #12a) in which he presents the Dual Fader.

    My first take-away was the simple idea of using one half of a cross-fader as a VCA with an RMS curve, and so I put together a little Audulus VCA and a comparison patch with exponential and logarithmic curves.e

    —Huffduffed by rudigermeyer

  2. Modular Diary · 24 Mar, 2018 · 5:12 PM · Rudiger Meyer

    Looking through, organizing, and reviewing the many Audulus patches that I’ve accumulated and worked on over the last year, I was reminded of the Hordijk TwinPeak filter. A simplifed version of it was included in the Blippoo Box that I’d put together, and I remembered that I’d meant to make a standalone version of it at the time – only to realize that that had already been tackled on the forum.

    Here’s my fresh take on the Epoch Modular version demonstrated in the James Cigler video at the top of the forum thread, building on the updated modules and approaches that have been introduced over the course of the last year.

    —Huffduffed by rudigermeyer

  3. Modular Diary · 11 Jun, 2018 · 9:39 AM · Rudiger Meyer

    I’ve put together a new version of the Hordijk Dual Envelope with updated internals – this time with envelope A placed on the right. Since the ADBDR modulation inputs will probably mostly be run via the S&H, it seemed more practical to avoid having the internal patching cross over the knobs too much. I found myself sometimes inadvertently attaching the S&H output to the knobs themselves as I attempted to detach it from the modulation inputs with the previous UI.

    The patch is available on the Audulus forum.

    —Huffduffed by rudigermeyer

  4. Modular Diary · 25 Mar, 2018 · 4:32 PM · Rudiger Meyer

    I’ve also put together a version of the TwinPeak filter following the layout and design Rob Hordijk created for his own modular system. It doesn’t have the cross-fader that is a handy feature of the Epoch Modular version, but that’s not necessarily needed in the context of Hordijk’s system since it includes a Dual Fader module. There’s a directness and clarity in the pure symmetry of his design that I find very satisfying.

    The site appears to no longer be online, but can fortunately still be accessed via the Internet Archive’s Wayback Machine. I also discovered the recently established Hordijk Modular Blog, which has an enthusiastic entry on the TwinPeak filter that includes an informative video in which Hordijk himself explains how the design enables not only a bandpass filter, but one with two peaks.

    —Huffduffed by rudigermeyer

  5. Modular Diary · 26 Mar, 2018 · 12:23 PM · Rudiger Meyer

    I’ve also put together a simplified, single input, micro version of the TwinPeak filter. The modulation input is set to only alter peak 2 by default, but this can easily be changed by opening up the hood and changing it to peak 1 or adding it to both.

    The Hordijk Modular Blog suggests using multiple TwinPeak filters in order to achieve a complex filter with multiple resonant peaks, so I’ve tried something of that out in a little demo with the filters being triggered at sub-audio rates.

    —Huffduffed by rudigermeyer

  6. Modular Diary · 11 May, 2018 · 11:15 AM · Rudiger Meyer

    Here’s my first take at putting together a Frequency Shifter in Audulus. Once again, one of Rob Hordijk’s NOVARS tutorials has provided the inspiration and point of departure.

    Hordijk describes the frequency shifter as kind of luxury ring modulator – with the added feature that it’s possible to split the upper and lower sidebands and achieve some special transformations through that. In essence it’s a ring modulator and an all-pass filter network, with the filters making it possible to remove one of the sidebands through phase cancellations.

    The all-pass filter is something that Hordijk covers succinctly in his video on the Physics of Sound, and I’d already made one on the basis of his description while putting together an Audulus version of his Dual Phaser. While Hordijk provides a good explanation of the principles behind the frequency shifter and a thorough demonstration of his own module, I needed to do a little detective work before I could figure out what was going on with the filter network.

    —Huffduffed by rudigermeyer

  7. Modular Diary · 9 Jun, 2018 · 5:56 PM · Rudiger Meyer

    Here’s envelope B from the Hordijk Dual Envelope generator, updated as with envelope A, as a little standalone module.

    The repeat mode makes for some interesting rhythmic possibilities: On its own, without an incoming gate but with modulation on the attack or release, irregularly fluctuating rhythms can easily be set up. Alternatively, when used in conjunction with incoming gate pulses, slight anticipations or ‘off’ beats that don’t exactly fit the clock grid can be created.

    I’ve uploaded a demo patch to the Audulus forum. Toggle the master clock in the patch to get an idea of how it works.

    —Huffduffed by rudigermeyer

  8. Modular Diary · 21 Jun, 2018 · 11:43 PM · Rudiger Meyer

    I’ve taken a few extra steps with my Audulus version of the Hordijk OSC SYNC. As much as I’d enjoyed the wide range that came with not having any tracking between the syncing and synced oscillators, I realized of course that as soon as sequencing is introduced, tracking becomes desirable/necessary. Along with a tracking switch allowing selection between full, 2/3, or 1/3 (around ‘c.v.’ = zero as a reference point), I also added an external input for the sample and hold.

    Using external modulation with the S&H allows for some interesting effects. I’ve uploaded two demo patches to the Audulus forum: In the first the TwinPeak filter is pinged with low pulses creating a resonant percussive sounds. It’s fun to explore the different timbral results that can be obtained by simply changing the tracking setting. The second patch creates an arpeggiator like effect – with this one it can be fun to turn up the modulation dial and/or add some subsquare modulation.

    —Huffduffed by rudigermeyer

  9. Modular Diary · 23 Apr, 2018 · 4:00 PM · Rudiger Meyer

    After taking a look at the NOVARS Rob Hordijk tutorials on the Physics of Sound and his Dual Phaser, I was keen to try out some of the ideas in Audulus myself.

    The Physics of Sound video takes a look at phase shifting and All Pass Filters, and as a tryout I used the 1 Pole LPF in the Audulus library as a starting point for an APF with nice resonant qualities, and then used that as a point of departure for putting together a phaser along the lines of Hordijk’s Dual Phaser. He adds some nice touches such as a switch that flips the direction of half of the modulation input, or keeps half of it static while the other half moves, as well as a fader between the LP and Phaser modes.

    I find the nicest thing is being able to push up resonance and then trigger the phaser with sub-audio pulses for some nice percussive sounds.

    I posted some demos on the Audulus Forum.

    —Huffduffed by rudigermeyer

  10. Modular Diary · 17 May, 2018 · 9:59 AM · Rudiger Meyer

    I’ve made a small start on putting together an Audulus version of the Hordijk Dual Envelope generator.

    Hordijk mentions in one of his videos that designing an envelope generator is perhaps the most difficult of all the modules in that there are so many possibilities to consider, and that certainly rings true as I’ve begun to explore it.

    In this first small patch I’ve adapted some of Stephen Schoen’s uLope modules to include a trigger mode – i.e. the attack time of the envelope is independent of the gate time. This means that a short trigger can result in a long attack swell, or a short attack can be triggered with a broad gate. It’s a simple feature that opens up a number of possibilities. With the attack time set to longer than the clock rate the envelope generator can suddenly starts to function as a kind of clock divider, as Hordijk points out in his NOVARS tutorial video. With in-between settings, e.g. with the gate setting in before the release stage has completed, interesting rhythmic effects can arise.

    I’ve uploaded the patch to the Audulus forum.

    —Huffduffed by rudigermeyer