The patches makes heavy use of panning, so the name comes from the sensation of the delays chasing each other around the stereo field. Along with panning, the patches offer a very granular approach to the multi-tap delay, with control over the levels of each tap, its timing, and how the regeneration path works (and in the case of Chaser Gran, pitch as well). That allows for a lot of novel sound design options, from stereo rhythmic delays (Chaser Stereo) to swirling quasi-reverbs (Chaser) to arpeggiating ping-pong delays (Chaser Gran) and a lot of other possibilities besides these.
The patches are:
Chaser — a five-tap delay with low- and high-pass filtering and diffusion
Chaser Stereo — a simpler five-tap delay with a true stereo wet signal path
Chaser Grain — a four-tap delay with granular pitch shifting (and other granular options)
Some background: If you’ve heard me talk about shift registers, you’ve probably heard me compare them to a bucket brigade delay before. And that was really how this patch came together, for me; I was working on the idea of using delay lines as a shift register (totally works as an alternative to the sample and hold methodology I’ve espoused before), and I thought: well, heck, what if I just make it an effect, rather than a generative piece, and then you can feed whatever you want into it. (If you cut out the regeneration and feed it a sequence or a drone or something where there’s a steady change, this origin becomes more obvious. But regeneration is fun.)
There’s a lot of controls, and if you watch the video, which is rather long, you might get the sense that this patch is overwhelming. Maybe it is, but I think a lot of the core ideas are familiar ones, so it’s really just a matter of familiarizing yourself with how they work together in this patch.
The dry signal path on all three patches is stereo. The wet signal path on Chaser Stereo is “true stereo” (the quotes are because although there are stereo delay lines and VCAs and panners, any time panning gets involved you’re changing the stereo path, so…). Chaser and Chaser Gran sum the input to mono before producing a stereo image.
SHARED CONTROLS (used by all three patches):
Left stompswitch — TAP TEMPO. You can also tap the tempo on the blinking UI button on the control page. The patch also accepts MIDI clock. There is a clock divider located on the page labeled “Tap.”
Across the top row are PAN BUTTONS that set different panning schemes.
These schemes are:
Side to side — taps move from one side of the stereo field to the other
Side to side exponential — taps move from one side of the stereo field to the other, but the progression is exponential, resulting in the taps growing progressively further apart (and bunching at the beginning)
Inside out — taps move from the center of the stereo field to the sides
Outside in — taps move from the sides of the stereo field to the center
Pattern I & II — pre-programmed schemes that swirl around the stereo field
User — programmable pan scheme (the user pan controls are found on the second page)
Random — each time the button is pressed a new random distribution of pan settings is produced
The pan schemes are controlled by a PAN SPREAD control, located below the random pan button. This controls goes from 1 to -1. With negative values the panning scheme is inverted, so a side to side pan, for instance, will move in the opposite direction (e.g. right to left instead of left to right).
Below the pan buttons are LEVEL controls for each of the tap. You can use these to create different intensities for each of the tap, or to emulate things like decay between taps (using progressively lower levels) or ghost notes (by having a lower level tap follow a full-volume one). If you want fewer taps, you can, of course, mute a tap by lowering its level to 0. (The tap will still remain a part of the delay network, which can have some interesting effects if, for instance, you use a muted tap as the regeneration point.)
Below the level controls are TIME OFFSET controls. The time offsets allow you to move delay taps off the base tempo. You can apply a positive or negative value to the base time, offsetting it by up to 200% (with positive values; 2x the base delay time, or a half note), or down to 0% (no delay). Since the delays are in a series, the offsets accumulate. For example, if delay 1 is offset by -.5000 (50% of the base delay time, or a quarter note), and delay 2 is not offset (100% of the base delay time, value 0), delay 2 will be 150% of the base delay time from the initial sound source.
The DELAY TIME control allows you to manually set the delay time; this is particularly useful for very short delay times or very long delay times (the base delay time can go up to 4 seconds; the patch uses 8 second delay lines, but since the time offsets can multiply the base time up to 2x, the input of this control is capped at 4 seconds. You can tap in times up to 8 seconds, but the positive time offsets won’t work correctly beyond 4 seconds).
The REGEN TAP pushbuttons allow you select which tap is used for regeneration. Changing the regen tap will produce different rhythmic qualities, especially in conjunction with the time offsets. The REGEN SUM button sums the output of all the taps and uses that for regeneration. The REGNERATION control determines the amount of feedback in the delay network. Regeneration is not affected by the tap levels, with the sole exception of the SUM option.
The DRY LEVEL and WET LEVEL controls are used to set the mix. Keep in mind because there are five different taps (essentially five copies of the input), the wet level can be quite loud, depending on the source.
LOW-PASS and HIGH-PASS FREQUENCY controls set the cutoff frequency of the filters, which form a variable bandpass. The filters are located in the wet signal path and the delay feedback path, so they will have progressive effects upon the repeats. By lowering the low-pass filter frequency, for instance, the repeats will become progressively darker, while increasing the high-pass filter will cause the repeats to lose low-end.
The filters’ Q controls set the intensity of the filters. At around ~.5000, they have the most “neutral” effect. Above .5000, they will (subtly) add gain at the cutoff frequency, which, with a high regeneration level, can cause the repeats to emphasize the cutoff frequency. Below .5000, they will more aggressively cut volume at the cutoff frequency.
The MOD RATE and MOD DEPTH control the triangle modulation of the first delay tap. The mod depth control is scaled in such a way that from 0 to ~.2000 the modulation is traditional pitch modulation. As you push the control above .2000, however, the pitch shifting becomes much more extreme, resulting in all sorts of mangled and tortured delay sounds.
DIFFUSION controls the mix of diffusion in the wet signal path and the delay feedback path. At 0, the patch functions as a traditional delay. As the diffusers are mixed in, you hear a combination of regular delay taps and diffused/smeared delay taps. At 1, the entire signal passes through the diffusers, producing a quasi-reverb/”cloud”-like quality to the sound.
CHASER STEREO-SPECIFIC CONTROLS:
MOD RATE and MOD DEPTH — see explanation in the CHASER-SPECIFIC controls
CHASER GRAN-SPECIFIC CONTROLS:
While Chaser and Chaser Stereo share many commonalities, Chaser Gran, while built from the same foundation and sharing many controls, is also the most different of the three. In order to make room for the granular modules, the numer of taps is decreased from 5 to 4. Additionally, the granular modules themselves impose a latency as audio is recorded and played back (this is governed by the grain size, so larger grain sizes will have a more pronounced additional delay). This means that some of the rhythmic elements, while still present, have less of an effect on the overall sound — the choice for regeneration tap is governed more by the pitch of the granular delay being tapped, I would say, than the rhythmic implications of using that tap (of course, both may be considered when making the selection). That said, it’s a lot of fun to play around with, I think.
Each tap has a PITCH control. These can be set positively or negatively to produce arpeggios and shimmering or descending delays (via regeneration).
GRAIN SIZE sets the size of the grains used for the delays. Below ~.7000, aliasing and other distortions become more pronounced. Above .7000, the pitches will be more pronounced. As the grain size increases, the added delay will become longer.
TEXTURE controls the envelope that affects the grains. At 0, no envelope is applied. At 1, the envelope is a smooth attack-decay (triangle shaped). Points in between have a trapezoid shape. More texture will generally produce a smoother sound. It also affects regeneration, as higher texture grains are lower in overall amplitude.
DENSITY affects the number of grains present, but generally it applies a tremolo-like quality to the sound.
POSITION MOD RATE and POSITION MOD DEPTH control the rate at which each granular module’s position is independently randomized. The depth determines the degree to which the position can be moved. The position modulation produces stutters and glitches, along with sounds that can sound as though playing in reverse or out of order. Cool stuff.