Dave Smith Instruments MONO EVOLVER KEYBOARD - Manual (Page 13)

The Evolver Voice
This section provides a brief description of the architecture of a single Evolver voice.
The signal flow diagram on the next page is a good starting point for understanding
how the Evolver works.
The Analog Side
The analog electronics consist of two identical (Left/Right) synth sections, each with
an analog waveshape oscillator, a 2/4 pole resonant lowpass filter, and a Voltage
Controlled Amplifier (VCA). Control voltages are generated by the processors to
control the analog components.
The Digital Side
Surrounding the analog electronics is a high-speed Digital Signal Processor (DSP)
that both pre- and post-processes the audio signal. Since the DSP also computes the
control voltages for the analog circuitry, it can handle a wide range of modulation with
high precision.
The DSP provides audio functions such as the Digital Oscillators, Envelope Follower,
the Peak/Hold detector (and associated external trigger generator), Highpass filter,
Distortion (with noise gate), Pan, Delay, and Hack. It also handles the tuned
feedback, as well as the additional Delay feedback paths and all the modulation
calculations (envelopes, LFOs, routing, and so on).
Analog-to-Digital (A/D) and Digital-to-Analog (D/A) converters are used to connect the
analog and digital sections. There are two sets of stereo converters running at a
48 kHz sampling rate with 24 bits of precision for minimum impact on the analog
sound.
Audio Inputs and Outputs
There are several audio jacks on the rear panel. All are unbalanced stereo pairs (two
mono jacks). First, there are the Audio Inputs for using the Evolver as a signal
processor.
Next are the Stereo Outputs. If you only use the Left/Mono jack, you will get a mono
mix of both channels – but you really should use both channels! Finally, there is a
stereo headphone jack on the rear panel.
Note: Always turn down your mixer/amplifier volume when turning the instrument
on or off to prevent pops!
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