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Page 22
Chrome Tone
User’s Manual
The Wah controls are:
• Threshold - the level at which the envelope follower is triggered. When the input signal rises above the threshold,
the envelope ‘opens’ at a rate determined by the Attack control. When the input signal drops below the threshold,
the envelope ‘closes’ at a rate determined by the Decay control. .
• Depth - the amount (positive or negative) the envelope follower affects the Wah (or other filter) frequency (or
Tremolo gain, or Chorus delay length).
• Attack - the rise time of the envelope follower.
• Decay - the fall time of the envelope follower.
• Mod - the amount (positive or negative) the envelope follower affects the Auto section’s LFO Shape mix, Rate, or
Depth amount.
• Split - separates the envelope follower signal into a left and right channel, each with the reverse polarity of the
other. This allows one channel to increase the Wah filter (or other filter) frequency while the other channel
decreases the frequency.
• S/R/D - enable or disable the modulation of the Auto section’s LFO Shape, Rate, and Depth.
• Input - selects incoming audio, side chain audio, MIDI note, MIDI velocity, or MIDI controller (1-128) as the source
from which the Dynamic envelope follower is triggered. When the Input selection is the MIDI controller, two
additional text readouts appear. One indicates the selected MIDI controller number, and the other displays the
currently recieved MIDI controller number.
The Input control of the Dynamic section opens up a new dimension in possibilities. The use of the input audio is the
most common envelope-wah setup. Chrome Tone Wah also allows a separate audio signal to be used as the input to
the Dynamic section via a side chain mode. MIDI data, including note, note velocity, and controllers (1-128) can also be
selected as the Dynamic section input.
An innovative way to sync the wah (or other filter) frequency modulation to MIDI beat clock is to use already synced MIDI
data as the Dynamic section input. Not only is the input signal more diverse than any periodic one from the Auto section,
it can be generated from any of the sophisticated MIDI editors found in digital audio workstations. Groove and swing
information can also be included in the MIDI data timing itself, for even more realistic syncopated rhythmic effects.
Split mode can create great stereophonic sounds when the frequency control is setup to roughly 50 (halfway up the
signal spectrum). As input is received in the Dynamic section, the filter frequency is decreased in one channel while
being increased in another. Useful not only in filter modes such as wah, low pass, and high pass, but also in the various
phasor modes available in Chrome Tone Wah.
Modulation of the Auto section LFO is done using the Mod control in the Dynamic section. The ‘S’, ‘R’, and ‘D’ LEDs
enable the modulation of the LFO Shape, Rate, and Depth, at an amount determined by the Mod control. Positive
values increase the Shape, Rate, and Depth controls in their respective clock wise positions (shape modulates towards
shape 2, rate increases up to 2x faster, Depth increases). Negative values increase the Shape, Rate, and Depth controls
in their respective counter-clock wise positions (shape modulates towards shape 1, rate decreases up to 2x slower, Depth
decreases). Note the modulation of the LFO rate has no effect if the LFO is synced to MIDI beat clock.
Auto Section
The Auto section is a configurable LFO (low frequency
oscillator) used to modulate the Wah (or other selected filter)
with a periodic waveform. There are two waveform shapes
that can be mixed in realtime, and the second shape can be
a multiple of the first. MIDI beat clock syncing is available
along with a groove control.
