Grayscale Helix is a new supercharged version of the Mutable Instruments Plaits macro oscillator with new algorithm, mod bus, and more.
The Mutable Instruments Plaits macro oscillator module is one of the most popular oscillators in Eurorack. Due to its open-source nature, it is also probably the most cloned oscillator.
There are 1:1 clones and versions that extend the feature set. For example, the $99 Behringer Brains offers more algorithms than the original module with firmware 1.2. Grayscale, which already has supercharged the MI Frames with features (Nexus), is doing the same with the Mutable Instruments Plaits in the Helix module.
Grayscale Helix
Helix is a supercharged version of the open-source Mutable Instruments Plaits macro oscillator. Grayscale described it as a revolution of the original module. The developers have completely redesigned it so the front panel no longer resembles the original. 12HP has now become 18HP.
Grayscale Helix’s eye-catcher is a new LED matrix that visualizes the algorithms and additional features. The module also uses new hardware that makes the new features possible.
Helix features all 24 algorithms from the final Plaits v1.2, including phase distortion and modulation, 2-voice 6-operator FM synth, wave terrain synthesis, and more. According to Grayscale, the module supports custom user data, which can be generated using the online Plaits editor.
The original algorithms and feature set are the foundation on which Grayscale built the new features for its supercharged Plaits version.
New Features
The first addition is a new algorithm. The Lo-Fi oscillator combines a Buchla-inspired Sine-to-saw waveshaper with bit rate and sample rate reduction. The new model generates crunchy, harmonic distorted sounds.
Then, the Helix features all-new pitch quantization with 35 scales, covering traditional musical territory and obscure microtonal experimentation. You can set the scale, root note, root octave, and octave range.
Another highlight is the new parameter randomization. More precisely, it allows you to infuse random modulation to the DSP parameters of the algorithms: frequency, algo, amp timbre, harmonic, morph, and decay.
This can be done with the LED matrix and additional random depth and bias settings per parameter. Also onboard is a new modulation bus accessible via the new CTRL input.
It allows you to replace the internal envelope with an arbitrary external control signal. The latter is routed to all seven CV inputs simultaneously with attenuators on each parameter, giving you flexibility. The internal envelope remains accessible on the front panel and can be cross-patched to one or more parameters.
Further, Grayscale Helix also offers more hardware control than the original module. It ships with dedicated knobs for the LPG/VCA level and envelope decay that makes the hidden parameters accessible.
On top of that, you can externally modulate the envelope time, and it is now accessible as a mod source via two new outputs: envelope and end of decay (EOD).
First Impression
At first glance, it is a beautiful, impressive upgrade of the original Mutable Instruments Plaits. Unlike the OG, I like the possibility of controlling the envelope on the hardware.
It’s a shame that Grayscale doesn’t participate in the open-source community. At this point, Helix is not available for other developers. They promised it for Nexus, but this hasn’t happened yet, or I missed it.
Grayscale Helix is available now for $399.
More information here: Grayscale
imho, the main drawback of the original hardware, and eurorack in general, was the poor resolution and repeatability of attenuvertors. these space savings come with a cost. a center detent pot with knob would be more welcome.