Electro-Harmonix MOD 11 Manual page 12

TZF Shapes – Barber Pole
In the TZF (through-zero-flanger) type, the default LFO shape is the sine
wave like in all other modulation types. The two other options are what
are known as barber poles. These are similar to the rising/falling
sawtooth, but instead of a hard reset at the minimum/maximum, the
LFO is done in a way where it sounds like it is going in a certain direction
forever.
ENVELOPES
In FLANGE, PHASE, and FILT types, you can set the LFO shape to be a
positive or negative envelope. When set to a positive envelope,
harder/louder playing will result in the modulated parameter being
higher, and softer/quieter playing will result in the modulated parameter
being lower. When set to a negative envelope, the opposite occurs.
When set to an envelope, the RATE knob (not in secondary mode) sets
how quickly the envelope responds to your playing.
SELECTING LFO SHAPE / ENVELOPES
For the six mod types that can use different LFO shapes, the shape is
selected with the RATE knob while in secondary control mode (see page
7). Below are diagrams of where on the knob you can select each shape
for each of the six mod types:
TREM VIBR & PITCH
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