Sonic Crayon Hollow Earth



Sonic Crayon

The Hollow Earth is a sort of waveshaper effect. Extremelly low-frequency waveshaping. It doesn't really affect the harmonics or "tone" of whatever you're playing, but the volume dynamics. Imagine you have a volume pedal and you like to swivel extremelly complex patterns and swells with it. If you do it inhumanly fast, you can make a neat tremolo with crazy variations to the pulses. That's basically what it is!

Hollow Earth allows you to "swivel" volume dynamics using the shape knob, and then loop the whole process automatically, change its speed, edit and "overdub" dynamics, and pluck-trigger it at will. It doesn't record and loop-back actual sound, it records and loops back volume changes. They can be super slow, subtle and span over thirty seconds, or sped up to trem speeds or even nearly ringmod speeds.

Loopable volume automation that you can find in audio software...... in a stompbox. It's a tremolo. It's a "slow-gear". It's a sublte fluttering added to your ambient drones! It's a ray gun that makes your guitar sound like death lasers!

Main attributes:

  • custom recordable/loopable volume dynamics
  • switchable attack mode triggered by pluck/sound
  • 10 non-volatile banks worth of storage
  • depth and smoothing tweaking
  • a random dynamics shaping mode
  • edit (or "overdub dynamics") mode
  • expression-out, use as a virtual expression pedal
  • 2.1mm 9v DC "boss style" plug


The heart of the system is a "record" stomp switch, and a "shape" knob. You start by holding down "record" and move the "shape" knob in a way you would a guitar's volume knob, or a volume pedal. Create a complex series of rises and falls and release "record" when you're done. It will immidiatelly start looping the dynamics back as you play whatever instrument or sound through, altered! You can adjust the rate of it all with the "speed" knob, during looping or record. There is also "depth" controllike that found on regular tremolos, and a "smooth" control that can even out the shape. "trigger" mode and its accompanying "sensitivity" knob turns it into a "slow gear" kind of effect. The volume dynamics never loop, and only start up when a guitar pluck is detected or a sound is played.

Toggling "random" mode makes it disregard anything that was recorded, and just uses random "noise" as variation in volume. In this mode, the "speed" knob changes the frequency of the noise, and the "shape" knob randomizes the length of time for each random "pulse". Toggling random mode off brings it back to its original state.

Toggling "edit" mode means that when you have an already-looping pattern, holding down "record" overdubs knob shape changes on the already existing loop. Use it to correct mistakes or for on-the-fly dynamics evolution.

There is an "expression out" jack that, when hooked up to another effect with an expression-in jack, can serve as a programmable expression pedal.

You can store patterns in up to ten banks. Select a bank with the "bank" knob and LED display, hold down the "store/recall" button for a couple seconds to save it. The display will blink for as long as it's saving. Complex patters that are half-a-minute long can take a few seconds to save, while simple ones will be nearly instantaneous. Tap the same button to recall the selected bank. All banks are saved even when the effect is off and unplugged.

An important note on the length of time a pattern can be recorded and the speed setting. When recording with the "speed" knob in the lower range, longer patterns can be recorded. Up to a few minutes. However the resolution (or detail) is reduced in this range, and some choppyness might be present. When recording with the knob in a higher range, the resolution is increased and you can pack more intricate details in your dynamics! It comes with a price thoguh, and the maximum recordable time is reduced to maybe 20 or 30 seconds. Crank it up even higher, and it's only a few seconds max.

This just means that if you record complex patterns in the slow range, then speed it up, you'll be "playing back" the dynamics at a much greater speed than is possible by hand with a volume knob or volume pedal. Recording a minute of patterns at a slow speed will turn it into a few seconds of detailed glitchy stutter at high speed, and recording just a couple seconds at slow speed will bring it up to near ringmod speeds at high! Use it to your advantage!

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