Multitimbral Eurorack Synthesizer Module

US OXI Instruments Coral features eight-voice polyphony 31/08/23

OXI Instruments has announced availability of Coral, which they say is the only multitimbral synthesizer module marketed for Eurorack

They told us, "Coral embraces eight-voice polyphony (freely splittable into different parts and allowing every parameter to be independently set for each voice or part) and several sound engines (each assignable to different voices) all accessible via a colourful, organic interface arranged around an anodised and beautifully silk-printed aluminium panel, premium finished with custom aluminium knobs, empowering users to create basslines, drones, drums, pads, and riffs while effortlessly manipulating voices independently to craft complex patches out of the box."

Here's more details direct from the company...

Ultimately utilising lots of computing power to deliver rich-sounding engines in an eight-voice package that could conceivably be termed the ultimate multitimbral synthesizer -- depending on the sound engine involved, one voice can have up to eight oscillators, meaning up to 64 oscillators playing at once making for a massive sound, for example, Coral can be played in a number of ways. While it is fair to say that it breaks free from conventional polyphonic synthesizer behaviour, Coral can conveniently be played polyphonically using only one CV (control Voltage) and gate connection, allocating a new voice every time it registers a new note -- be that part of an arpeggio, strummed chord, or pad with long decayed notes -- on the oct (V/Oct) input. Independent filter, amplifier, and modulation envelopes are available to each of those voices -- in fact, every parameter can be independently set for each voice, including individual effect sends! It is also possible to play all eight voices in unison -- all voices playing the same note for drones and thick textures, as well as triggering the internal envelopes with the trig input or directly controlling the amplifier level with the amp CV.

Coral also benefits from full MIDI (Musical Instrument Digital Interface) integration, meaning multitimbral operation is a given while also allowing for control over any part's parameter via MIDI CC (Continuous Controller) commands. Indeed, its eight voices can be freely split into different parts; this time, every parameter can be independently set for each part to craft complex patches out of the box. But there's more: once those voices have been grouped across different parts, users can distribute the modulation signals across them using the part CV; so, for instance, if there are two parts, the first part will be addressed if the part CV voltage is between 0 and 2.5V while the second will be addressed if the voltage is between 2.5 and 5V.

But better still, several sound engines can be assigned to each of Coral's voices; included instances available from the outset are Virtual Analog, Waveshaping, FM (Frequency Modulation), custom Wavetable, MDO (Multiple Detuned Oscillator), String, HiHat Synth, Snare Synth, Digital Kick, and Wav Player, now boosted by new Additive with Wavefolder and Diode Distortion additions. As one such sound engine implies by name, Coral supports almost any kind of WAV file -- 16-, 24-, and 32-bit mono or stereo -- with no limit to playback time! Thinking outside the box comes easily when working with Coral -- add overdrive to samples, sculpt them using the filters and envelopes, pitch them up and down in tune, and even modulate the sample file or folder in real time using the CV inputs or MIDI CC commands! It is possible to load any wavetable WAV file to the SD card for Coral's Wavetable engine; wavetables can even be morphed into three dimensions using OXI Instruments' OXI Wave app -- based on the amazing Wave Edit app created by Andrew Belt -- that makes creating and editing them both fun and interesting in equal measures.

Clearly, Coral can go far beyond the realms of a conventional polyphonic synthesizer, then, thanks to the comprehensive voice management and manipulation on offer. On the face of it, those powerful sound engines speak volumes in and of themselves -- as does Coral's full-featured polyphonic sample playback plus built-in space (deep atmosphere) and chorus (rich ensemble) effects potential. It is, indeed, the only eight-voice polyphonic, multi-engine, multi- part synthesizer module marketed for Eurorack, one whose freedom of voice management is even hard to match in desktop gear. Going from rich polyphonic patches to a fully-fledged groove box with basslines, drums, and leads comes quickly to Coral, which, of course, can be fully controlled using MIDI and CV -- or both! All available to all in a compact (14HP) form factor for a reasonable price -- particularly when pitched against a conventional polyphonic synthesizer.

"The introduction of Mutable Instruments' Plaits module was a revolution in terms of compact, multi-engine synth voice modules," maintains OXI Instruments CEO & CTO Manuel Vazquez Rodriguez, good-heartedly giving credit where credit is due before digging deeper to end on a high note: "Thanks to their open source contributions, we have taken some of their algorithms and put them into a tasty, compact package that contains eight 'instances' of that module with custom-developed engines alongside new ingredients like independent envelopes and filters per voice, effects, full MIDI implementation, and a colourful, organic interface. On top of that, custom wavetables and a sample playback engine are also available per voice. But we didn't want to just create another polyphonic synth, so, to allow users to make the most of every voice, we've introduced the multi-part concept. Consequently, users can arrange and use the eight voices as they wish -- with eight monophonic parts, one polyphonic part of eight voices, or any combination thereof, such as two polyphonic parts of three voices each, plus two monophonic voices in the same module, meaning Coral can be corralled into acting as a versatile and powerful polysynth, drum machine, groovebox, and sound exploration module... all at the same time! We won't stop there, though, adding more features in future through regular firmware updates -- just like we've been doing with OXI One!"

Pricing and Availability:

Limited stock of Coral is available to order online directly from OXI Instruments' Store, priced at €399.00 EUR (excluding VAT) for EU (European Union) countries (with VAT being added at checkout for individual EU customers) and €459.00 EUR for ROW (Rest Of the World) countries (where duties and taxes may be charged on delivery) with worldwide shipping available.

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