Review of Convex multi-effects processor (VST/AU) by Glitchmachines


Introduction
Glitchmachines have updated Convex to version 1.2, a multi-effects processor designed to facilitate the creation of contorted artifacts, syncopated patterns and skewed digital textures.
It is available for Windows and Mac as a 32 bit and 64 bit VST/AU plugin typically priced at $39 available direct from Glitchmachines. The update is free update for existing customers.
The version 1.2 update retains the core functionality of Convex but brings a whole host of improvements –

  • Completely rewritten code
  • Completely redesigned and resizable user interface
  • Individual DSP randomisers
  • Improved midi learn with randomise button midi mapping
  • Filter output saturation
  • Module info tooltips
  • 70+ brand new presets
  • Various bug fixes and internal changes

Note that because of the substantial code changes, Convex 1.2 is not backwards compatible.
For more information, see the intro and quickstart video:

Background
Convex is a multi-effects processor that can be used to process any audio signal, including real time audio or hardware synths or guitars. It has dual multimode filters, dual delay and dual pitch shifters and generates dynamic variations by morphing between these two instances of each effect. However, the real creative power of convex is with the extensive modulations options which is typically seen in Glitchmachines VSTs. There are 4 LFOs and 2 envelope followers which can modify various parameters and this modulation is extended beyond LFOs / envelopes because they can have their output inverted or combined using mixers and multipliers.
What this means is that the effect is capable of anything from simple dub-type delays to extensive glitch sequences. What I really love about Convex is the power / flexibility and the ability to surprise. When you think you know what sort of a sound you are going to produce, you often get unexpected results.
In-depth Review
The UI has been completely redesigned which improves the workflow whilst retaining the clean, modern look we typically see from Glitchmachines. It’s split into three sections:
The effect modules and output are located at the top of the display;

The centre section contains envelopes, LFOs, mixers, multipliers and inverters;

The bottom section has midi, presets, global randomisers, global menu and panic button;

Other changes in the new version include:

  • The use of 4 colour coding options for different processes which are fuschia for audio processing, green for modulation source, blue for audio output and light blue for targeted parameters;
  • Tooltips are available by hovering your mouse over a module’s header label;
  • Parameters that may require precise adjustment have been provided with a parameter display pop-up when you adjust them;
  • The interface is resizable by dragging the bottom right of the window.

The filter module has two multimode filters with crossfade-style morphing and the option to modulate cut-off and morph parameters. Version 1.2 brings a new drive control that adds saturation to the output. Depending on the ‘pre’ setting of the delay module the filter will either process the input signal or delay module output. The filters can also be set to bypass by selecting the type as ‘none’ which you do by dragging the filter curve icon. Three filter types are available – low pass, band pass and high pass.

The pitchshifter module has two pitchshifters with crossfading and the option to modulate the pitch, crossfade and mix. The size control adjusts the buffering length and feed is the amount of signal returned to the input.

The delay module has crossfade-style morphing and the option to modulate the delay time, crossfade and mix. The delay can be set to tempo-sync, otherwise it can be set in ms up to a maximum of 1000ms. The ‘pre’ parameter places the delay before the filter input otherwise the delay module will be placed just before the out module.

Each of these modules have a randomisation option which is the ‘?’ in the top right corner.
The output module gives you control over the amplitude and dry / wet mix of the effect. The dry/wet mix can be modulated.

Where Convex comes into its own is the extensive modulation options that can be combined to create really complex modulation parameters. Each parameter that can be modulated has a small crescent knob and a mod source menu next to it – this applies to the cutoff, filter morph, pitch, pitch morph, pitch mix, delay time, delay morph, delay mix, LFO rate, mixer’s ‘mix’ parameters and global OUT. The modulated parameter’s current value is used as the floor value for modulation. The modulation depth knob then represents the range in percent that will be used for modulation between the current parameter value and the maximum parameter value.
There are 2 envelope follower modules with sensitivity (gain), attack and release settings.

There are 4 LFOs with a wave menu to click and drag to choose the waveform and a rate which can be set in hertz or beat divisions using the sync option. The rate value can also be modulated.

The multipliers convolve 2 modulators and use the resulting signal to modulate another parameter. These can be used to generate evolving modulation shapes.

The modulation mixers can be used in one of two ways, either to get the mean of two signals or to morph between two modulators using a mix control which itself can be modulated.

The inverters do exactly what you’d expect and invert a parameter which is especially useful to modulate 2 parameters in opposite directions using the original and inverted values.

There are also midi learn options, a randomise option and the usual preset options of load and save.
Conclusions
I’m delighted to have been part of the testing team and to have designed a number of presets for Convex. These range from subtle dub and subtle glitch to more extreme glitchy and percussion decimating effects. The new UI improves the workflow and it’s very easy to start using and creating your own effects. The presets give an excellent range of sound possibilities of Convex, you can also use randomise settings to create interesting sounds, though often you’ll need to tweak these to get the most out of them. It gets very interesting when you start using modulation and again it’s easy to get to grips with modulation options and you can use them subtly or in more extreme ways.
I’ve used Loopcloud (Loopmasters) to find samples and created the songs embedded at the top of the post. I’ve created them in MuLab 7 processing the samples with multiple instances of Convex as well as SP2016 Reverb and Ultrachannel (Eventide). I’ve used Convex with a range of subtle and more extreme settings.
The demo track created using the original version of Convex in Sensomusic Usine Hollyhock 2 is also embedded below. This uses Convex to process sounds from the U-Drone add-on, groove steps tool and a random midi sampler fed to Izotope DDLY dynamic delay. It has the feel of a monday morning when all you want is another 5 minutes but your alarm clock sounds like a thousand going off at once.

Loopcloud Sounds