Download Hiram Becker Music Synthesis Epsilon II Analysis Index I. Front

Hiram Becker
Music Synthesis
Epsilon II Analysis
Index
I.
II.
III.
IV.
V.
VI.
VII.
VIII.
IX.
Front Panel Layout
Voice Mode
Pitch Bend
Voltage Controlled Oscillator
Mixer
Voltage Controlled Filter
Envelope Pitch and Filter
Voltage Controlled Amplifier
FX
Prologue:
The Epsilon II is a multi-oscillator, additive/subtractive synthesizer with built-in FX
generators.
I. Front Panel Layout
Initially, there are two panels in the ensemble. The Epsilon Core and the Master. The
Master, when clicked on, is simply the master volume and tune control.
Click into the Epsilon synthesizer and begin dissecting the innards.
II. Voice Mode
The Voice Mode is one of a couple signal sources. Note Pitch and Gate live
here for developing the signal source.
The pitch can be affected by the PitchBend wheel, or the pb. It has a knob that
controls the wheel’s effectiveness.
There are also two switches in the Voice Mode that are identical, but one of them
outputs to a Gate, and the second is further affected by wave oscillators and can be
controlled by an on/off switch.


III. Pitch Bend

The Pitch Bend references it’s own Macro. Pitch Bend has a pb (I believe to be Pitch
Bend) and two fb (probably frequency bends) controls that are routed into
multipliers and additive Math Modules to rout them to the outputs 1, 2, and 3. These
are subsequently routed from the Pitch Bend Macro to pb 1, 2 and 3 of the Voltage
Controlled Oscillator. The PBend Macro is routed to the Voice Mode and the fb to the
Voltage Controlled Filter.
IV. Voltage Controlled Oscillator
Within the VCO are three separate Oscillators.
Each of these three oscillators has the ability to control the sawtooth, pulse and
triangle waveforms.
Its outputs flow to the Mixer and the levels of each oscillator can all be adjust there.
V. Mixer
The outputs of the VCO flow into the Mixer and the Mixer can adjust the levels of
each of the three VCOs within its Macro.
VI. Voltage Controlled Filter
The Voltage Controlled Filter has a panel list to filter between two filters. The same
variables affect either Filter. Both filters can play simultaneously in a number of
ways – either down the center channel, or in stereo. It directly affects the fader in
the VCOs’ tracks. There are a number of filters that the user chooses from in the
drop-down panel. A cutoff knob affects all the filters.
VII. Envelope Pitch and Filter
The Envelope Pitch and Filter Macro has two Macros in it – one for each of the
effects. Each of these has a Pitch and Gain terminal, connected to the appropriate
input, and these affect the envelopes within each of the two Macros.
The Macros are essentially identical. The Gain is dictated by the Velocity of the
keystroke, and the Pitch is, well, controlled by the keystroke.
VIII. Voltage Controlled Amplifier
The VCA is the master amplifier knob. Its inputs originate from
the Voltage Controlled Filter, and outputs to both the master amp knob panel and
the FX control.
IX. FX
Inside the FX Macro are three FX variables for fun usage.
Each of the FX can be turned on with a button in the FX panel, using one, two or all
of them in unison.
Given its position in the flow chart, it reminds me of an Aux bus.