Diva is the "Dinosaur Impersonating Virtual Analog" synthesizer created by U-he. The linux beta plugin demo version is available for download at the KVR link below. The limitation of the demo version is a noise signal at regular intervals. Purchasing the full version of Diva will remove the limitation. The audio demos above are of various presets included in the installation package.
Diva's focus is to emulate the zero-delay feedback filters common in old analog synthesizers. The GUI screenshots above show the five different available oscillator sections in Diva: Triple VCO, Dual VCO, DCO, Dual VCO Eco and Digital Oscillator. The Triple VCO selection is the most CPU-hungry, and may require changing the accuracy setting located at the bottom-center area of the GUI. Divine, great, fast and draft are the accuracy settings, similar to ACE. Lowering polyphony and stacking are other ways to reduce CPU load.
The Triple VCO section includes three oscillators in the left area of the panel, each with octave detuning just to the right. The first oscillator can frequency-modulate the other two oscillators (see the modifications panel area for further control). The ENV2 and LFO2 switches on the left are each associated with an oscillator, and can all be routed to another destination, by clicking on the label. Tune Mod will modulate oscillator pitch, and Shape Mod will modulate waveform shape. Although the waveform knobs indicate saw-up, triangle, saw-down, square and pulse, they are not stepped switches and can therefore morph smoothly from one shape to another. Fine detune knobs for oscillators two and three are included, as well as two sync switches, one for oscillator two and one for oscillator three. These hard-sync the respective oscillators to oscillator one. Also unique to the Triple VCO section is the mixer section: individual volume knobs, a feedback signal control, a noise signal level and a selector for pink or white noise. The envelope section to the right allows selection among three possible envelope configurations: two ADSR envelopes, two simplified ADS envelopes, or two digital ADSR envelopes (which include quantize and curve settings).
The Dual VCO option provides one less oscillator, but with other options, such as separate pitch control and multiple waves for both oscillators. The two sliders on the lefthand side can be dedicated to either oscillator one or both. They control pulsewidth and LFO2 or an assignable re-routing. Octave detune for both oscillators is provided, as well as sync, fine detune for oscillator two, 4-way routing switchn with signal routing to envelope 2 and LFO 2 (or other), cross modulation and level mix.
The Dual VCO allows to select between four options for the central panel: feedback, highpass filter (post-signal), highpass filter (pre-signal) or highpass filter bite. This last option is a complete filter with its own cutoff and resonance (peak) control and bi-polar depth knob. Two versions of this filter are selectable. Like the Triple Oscillator, this set-up includes the envelope options on the righthand side of the GUI.
The DCO set-up provides one single oscillator, with a sub-oscillator and noise control. Although a single oscillator, it allows to combine waveforms for a special quality sound. Of the types of sawtooth and pulse waves available, the straight line deactivates the respective signal, whereas the fourth wave of each is the one that reacts to pulsewidth modulation. The sub-oscillator has four different pulse wave options, set at one octave down. The last two wave options are detuned two octaves down. There are level sliders for both the sub-oscillator and noise. The DCO arrangement also includes the highpass option for the middle panel, as well as the envelope section on the right, just like the Dual VCO.
The Dual DCO Eco configuration is lighter on CPU usage. It has two oscillators, where the second one includes ring modulation capability. There are pitch modulation controls (Env 2 and LFO 2), as well as pulsewidth for oscillator one, octave detuning for both, and fine detuning for oscillator two. Highpass filter control options are provided, as well as the envelope section.
Finally, Diva includes the Digital Oscillator option. This configuration has two oscillators with the following unique waveshapes: Multisaw, TriWrap, Noise, Feedback, Pulse, Sawtooth and Triangle. Each of these waveshapes has its own controls, in addition to the global Env2, Cross and Mix knobs, as well as ring modulation, sync and high quality switches. As with the previous configurations, the Digital Oscillator also provides filter and envelope sections.
Diva's filter section includes five filter models to choose from: ladder, cascade, multimode, bite and Uhbie. The ladder filter has 24dB and 12dB options, as well as filter-FM for oscillator one (controllable in the modifications panel). Along with cutoff and resonance controls like the ladder filter, the cascade filter also has a rough-clean switch, keyboard tracking, FM oscillator control, and Env2 and LFO2 amounts--both re-routable. The multimode filter has additional bandpass and highpass filter options. The bite filter has its own unique sound, when set just right. The Uhbie filter is a 2-pole, state-variable filter which morphs from lowpass to highpass, passing through either a bandpassed or notched signal, depending on the setting of the switch located at the top center area of this same panel.
The lower half of the Diva GUI includes a variety of additional, global controls such as control of LFO 1 and 2, oscillator voice detuning, an oscilloscope, a voice map modulator, stack detuning, arpeggiator (visible when "Main" or "Patches" is selected), global tuning, microtuning, portamento control, quantize, rectify and more. The lower righthand area includes the following effects: chorus, phaser, reverb, rotary and delay.
Linux beta version of Diva at KVR