With Double Sawtooth, the Oscillator generates two saw waves that can be independently detuned. If all Oscillators are set to Double Saw, then each voice effectively has six Oscillators, with no effect on total polyphony.
Unison sounds can therefore be created without the need to use the Unison feature, again saving voices. However, it is also possible to Unison a Double Saw Program, creating truly huge sounds. In OS4, the Unison function also offers a preset detune feature.
Also new in OS4 is the facility to route a Program with stereo effects through a single mono channel. This enables the Program to be assigned to a single output without compromising the quality of its effects configuration, while releasing more outputs for use even when creating complex multi-Program Performances.
There is a punchy effects distortion feature, which incorporates a preset gain compensation facility, so that effects can be overdriven without an accompanying increase in volume. The new operating system also provides a pan option for effects.
Analogue modelling quality is enhanced by the DCO to VCO emulation, with a preset amount of the drift that is characteristic of classic analogue synths.
Alongside the standard analogue filters, there are nine additional Dual/Split filter types included on OS4 for the Nova, giving a much wider sound creation resource. These are accessed through the Special button in the Filter section and incorporate harder hyper-resonant filters and formant filters that enable the creation of sounds with speech-like qualities.
OS4 also includes Knob pickup, which eliminates the risk of sudden surges in volume or extreme changes when adjusting settings in real time. After switching between Programs, the knobs and sliders can be moved without altering the settings until they have reached positions corresponding to the new setup.
New MIDI functions include the ability to disable Program change and Controller transmit options, as well as forward compatibility with Novation’s Supernova II series synths – OS4 can accommodate sysex dumps from the Supernova II. In addition, the Finder mode that helps to organise and locate sounds has been improved by the facility to turn the demo option off.