UDO Super 6 — Owner’s Manual
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OVERVIEW
The UDO Super 6 is a 12-voice polyphonic analog and digital hybrid
synthesizer. By combining characteristics of the best of vintage-era classic
synths and state-of-the-art modern synthesis technology (more about
that below), it was designed to be a flexible, powerful and immediate
instrument that provides you with a gorgeous sound.
DDS-Oscillators
Direct Digital Synthesis is the signal generation method employed by
both oscillator cores of the Super 6. At its centre is a clock signal – three
orders of magnitude higher than typical audio sample rates. The clock
signal increments a counter through thousands of indices in your choice
of waveform, selecting the appropriate sample to output every twenty-
billionths of a second with interpolation filling in the gaps between
samples at different oscillator frequencies.
The samples produced by our numerically-controlled oscillators are then
transformed to analog voltages by a DAC, one for each oscillator, which
operates at the same clock rate before being filtered by a preliminary
analog low-pass filtering stage.
The extremely high sample rate to output frequency ratio provides DDS
oscillators with the advantage of superior phase precision and natural
sounding frequency modulation. It also, importantly, precludes us from
needing to deploy the severe band-limiting that is necessitated by aliasing
constraints of typical lower frequency digital methods. Thus our oscillators
are comfortably capable of generating frequency content far above the
upper-frequency limits of the human auditory system as is the norm with
analog oscillator synthesis.
