PHASERLOPE

PHASERLOPE

PHASERLOPE is an analog-flavoured phaser effect with built-in envelope follower. It was inspired by the vintage 2 and 4 stage phaser designs, but we’ve added a few twists of our own!

PHASERLOPE can be used as a standard phaser driven by its own LFO, or the depth can be set to follow the gain of the input signal, or an external sidechain.

PHASERLOPE is a stereo in / out module. When either input is used on its own, it will be routed to both outputs.

STAGES selects the number of stages between 2 or 4. Each stage is a stereo pair of bandpass filters that have their own unique minimum and maximum frequencies modulated according to the DEPTH and speed of the LFO. Two stages tends to sound mellower and reminiscent of the early small guitar effects pedals. Four stages has a bit more going on! The phasing effect is created due to the frequency ranges for the stages overlapping, so as the centre frequency is modulated for each stage, certain frequencies in the input signal are emphasised or reduced.

DEPTH sets the amount of frequency modulation applied to the phaser stages. At maximum, the modulation is applied to the entire frequency range of each stage.

SPREAD adjusts the left / right pan of the effected signal only. At minimum setting, the effect will be mono and as you increase the SPREAD control, the effect will get increasingly panoramic!

The FREQ A/B switch selects between different frequency ranges for the stages. Option A selects the theoretical ideal values. Option B uses the values from a well-documented National Semiconductor design and tends to sound ever so slightly thinner and brighter compared to A.

PEAK is our preferred alternative to having a phaser feedback or regen control, and it has a similar, but not identical effect. Increasing the PEAK control will emphasise the current frequency for each stage, which at extreme settings, can almost sound like a wah-wah pedal.

The LFO / ENV switch determines whether PHASERLOPE uses its own LFO (left position) to sweep across the modulation range (set by DEPTH) or whether to follow the envelope (ENV) of an incoming signal (right position).

When the LFO / ENV switch is in the centre position, PHASERLOPE is in envelope follower mode, but the left channel has additional modulation applied by the LFO. This creates a nice stereo effect.

When in LFO mode, the left and right channels are 90 degrees out of phase to create a stereo effect.

RATE varies the LFO rate from 0.01 to 5.0 Hz.

The DRIFT button, when turned on will introduce gradual variation to the LFO speed so the repeating cycle is not obvious and locked to a set time. This can be a useful effect when used with slower LFO rates.

SENSITIVITY varies the threshold of the envelope follower and determines the amount of modulation applied, according to the level of the input signal. When used in stereo, the average of the left and right channels is fed into the envelope follower.

The INVERT button, when turned on inverts the response of the envelope follower so that stronger signals decrease the effect instead of increasing it.

The LEDs between the RATE and SENSITIVITY knobs indicates the amount of modulation or a representation of the envelope follower depending on the LFO / ENV switch. When in LFO mode, the LEDs show the amount of modulation for the left and right channels. When in LFO / ENV (centre switch position), the right LED shows the envelope, and the left LED shows the envelope plus the amount of modulation being applied to that channel. In ENV mode, both LEDs show the envelope state.

The ENV section has dedicated knobs for attack, hold and release. This allows you to customise the response and feel of the envelope follower depending on your audio source. For example, for rhythmic material, you might want to use very low attack, hold and release times for a “snappy” response. Alternatively, when used with guitar for example, longer attack and / or release times can produce very interesting results.

ATK varies the envelope follower attack time from 5-1000ms.

HLD varies the envelope follower hold time from 10-1000ms.

REL varies the envelope follower release time from 10-2000ms.

Please note that the envelope follower applies damping to its input to help achieve a smooth response and nice “feel”. Because of this, you may still notice some “ramping” up or down, even at very short attack or release times.

Below the IN jacks is an ENV sidechain input. When an audio signal is connected to this jack, the gain of the incoming audio at this input is used to drive the envelope follower. Please note the ENV input is designed to accept audio and is not a +/-5.0 CV jack, i.e. negative values will be treated as positive.

We hope you might consider enveloping your sound in phasey goodness with PHASERLOPE!

Title of Song

  • KEYS-ECHOLOPE-PHASERLOPE