Difference between revisions of "ER-301/Clocked Doppler Delay"

Applications

For further details on applications, see ER-301/Doppler Delay.
• Inducing polymetric rhythms.
• A delay effect that tracks tempo changes.

Description

This delay unit is the same as the Doppler Delay unit except the delay time parameter replaced by a clock input with associated controls for clock multiplication and division. The delay time tracks the observed period of the (post-divided, post-multiplied) clock signal received from the clock parameter's sub-chain. The mult and div parameters can be used to set the multiplication and division amounts for the clock. Consistent with terminology commonly used in the modular environment, the multiplication/division operation applies to the clock signal such that multiplication shortens the delay time, division lengthens the delay time.

Parameters

clock

 Control Type Has Sub-chain? Sub-chain Parameters Behavior Threshold yes threshold (-1 to 1) trigger

The period of the clock signal coming from this parameter's sub-chain determines the delay time. The multiplier (mult) and divisor (div) parameters affect the clock frequency (not the period) in the typical manner for clocks in modular systems.

mult

 Control Type Has Sub-chain? Sub-chain Parameters Fader Scale Gain/Bias yes gain (-20 to 20) bias (1 to 32) integer

This parameter sets the multiplication factor that is applied to the frequency of clock. For example, a value of 2 will double the clock frequency and therefore cut the delay time in half.

div

 Control Type Has Sub-chain? Sub-chain Parameters Fader Scale Gain/Bias yes gain (-20 to 20) bias (1 to 32) integer

This parameter sets the division factor that is applied to the frequency of clock. For example, a value of 2 will half the clock frequency and therefore double the delay time.

 Control Type Has Sub-chain? Sub-chain Parameters Fader Scale Gain/Bias yes gain (-10 to 10) bias (-1 to 1) linear

In a mono chain, this parameter will appear as 'nudge' while in a stereo chain it will appear as 'spread'.

In the stereo/spread configuration the effect on the delay time is exactly the same as the spread parameter found in the Spread Delay unit:

$\displaystyle \begin{array}{lcl} \text{Left Delay} & = &(1-\text{spread})*\text{Delay} \\ \text{Right Delay} & = & (1+\text{spread})*\text{Delay} \end{array}$

For example, if the spread is 0.1, then the Left Delay is shrunk by 10% and the Right Delay is expanded by 10%. A spread of -0.1 would have the opposite effect. Subtle amounts will "spread" the repeats across the stereo field while more substantial amounts of spread will result in a kind of ping-pong effect.

In the mono case, the effect is essentially the same as the spread parameter's effect on the left channel but since there is only one channel, it makes more sense to think of the delay being nudged away from the clock-determined delay.

$\displaystyle \text{Nudged Delay} = (1-\text{nudge})*\text{Delay}$

This allows you to move the repeats "off-the-grid".

feedback

 Control Type Has Sub-chain? Sub-chain Parameters Fader Scale Gain/Bias yes gain (-3 to 3) bias ($\displaystyle -\infty$ , -36dB to 0dB) logarithmic

This value determines how much of the audio in the delay line to mix with the delay's input. A value of 0dB means that the old and new are summed together as-is and will eventually cause the contents of the delay line to grow so loud that it will clip when it arrives at the DAC. A value of $\displaystyle -\infty$ means that the new material completely replaces the old material in the delay line. Anything less than 0dB will cause the old material to slowly fade away with each (delayed) repeat. The following graph summarizes the number of repeats required to fade to 10% of the original captured amplitude vs the feedback amount:

wet

 Control Type Has Sub-chain? Sub-chain Parameters Fader Scale Gain/Bias yes gain (-3 to 3) bias (0 to 1) linear

This parameter controls the amount of the input signal and of the affected signal which is passed to the output. A value of 1 (i.e. 100% wet) means you will only hear the affected signal. A value of 0 (i.e. 100% dry) means you will only hear the signal received at the unit's input. However, the cross-fade curve is not linear but rather lifted to counteract the tendency for loudness to dip in the center of a linear cross-fade curve. The actual cross-fade curve looks like this: