The Hidden Power of Parallel FX: Transforming Mono Pedals into Spatial Tools

Mono effects pedals are at the heart of guitar tone. Many of the most characterful delays, modulations, and drive stages ever created exist only in single-channel form.

While stereo pedals can produce wide and immersive soundscapes, countless players assume that mono effects cannot meaningfully contribute to a stereo or wet/dry/wet rig.

Parallel processing—and specifically the Parallelarator—changes that assumption completely.

By placing mono pedals into parallel paths, blending them alongside the dry signal, and distributing their return signals into a stereo output matrix, the Parallelarator allows any mono pedal to create wide, dimensional, and spatially rich tones.

This article explores how parallel routing unlocks new behaviours from mono pedals and how the Parallelarator’s architecture makes this transformation intuitive and predictable.

What Is the Parallelarator?

The Parallelarator is a compact, studio-grade parallel mixer for pedalboards, designed and hand-built by Cosmic Loop FX in the UK. It takes a single mono guitar input and splits it into three independent effect loops, each of which can be blended back into a stereo or wet/dry/wet output field.

In simple terms:

It lets you run your pedals in parallel instead of in series, just like a recording engineer would on a mixing console.

This keeps your dry tone pure and articulate while letting effects create space, movement, and width around the core signal.

Key capabilities include:

• 3x parallel FX loops with independent blends

• Mono sends with mono or stereo returns

• Stereo output matrix with automatic mono/stereo/W-D-W adaptation

• Support for external mono or stereo sources

• Ability to combine multiple pedals in a single loop (series)

• Support for dual-mono setups using TRS splitter cables

• Footswitchable Loop 3 with effect trails preserved

  
  

The Parallelarator effectively turns any pedalboard into a creative stereo processor, unlocking spatial possibilities normally reserved for high-end studio equipment or rack systems.

Why Parallel Processing Makes Mono Pedals Sound Bigger

In a traditional serial pedalboard, a mono effect’s output becomes the entire signal. Whether it compresses, modulates, filters, or delays, the effect replaces the dry tone—often at the expense of clarity and dynamics.

Parallel processing works differently:

• The dry input remains intact, articulate, and centred.

• Each effect receives its own independent mono send from the dry input (unless you choose not to use the send—more on that later).

• The effect’s return is blended back in, from subtle enhancement to immersive ambience.

• Returns are placed into a stereo or wet/dry/wet output field.

This transforms even simple mono pedals into contributors to a far larger spatial image.

The Parallelarator’s Architecture:

What Makes This Possible

1. The Dry input is mono.

2. All loop sends are mono.

3. Loop mode (Mono or Stereo) affects only how returns are mixed, not what is

   sent.

4. Mono Mode duplicates the return to both Left and Right channels.

5. Stereo Mode preserves two independent return signals.

6. A mono pedal in Stereo Mode returns audio to the Left channel only.

All stereo width is generated in the return stage and output matrix, never at the sends.

You Don’t Have to Use the Sends:

External Sources Are Fully Supported

One of the Parallelarator’s most powerful features is that you are not required to use its sends. Pedals—or entire stereo processors—can be fed from external mono or stereo sources and returned into a loop for mixing.

This enables:

1. Feeding stereo pedals with true stereo input

Connect a stereo device (modeler, preamp, multi-FX, synthesizer, DAW output) directly into a loop’s stereo return jacks. The Parallelarator then blends that external stereo signal alongside the dry tone and other loops.

2. Using the Parallelarator as a parallel stereo mixer

Complex rigs—dual-amp setups, synth/guitar hybrids, rack effects—can feed their stereo outputs into the Parallelarator for final mixing and routing.

3. Hybrid guitar–studio workflows

Route stereo outboard processors or interface outputs into a loop return while preserving the dry instrument signal.

Key principle

The Parallelarator only controls how a return is mixed—it does not dictate what feeds the pedal.

Loop 3 Switching: Trails Are Preserved by Design

Loop 3 has a dedicated footswitch.

Crucially: The footswitch switches the SEND, not the RETURN.

This is intentional. When Loop 3 is switched off:

• The pedal receives no new input (send muted).

• The return remains connected.

• Any ongoing delay or reverb continues to decay naturally.

  
  

This creates smooth transitions and prevents abrupt cut-offs.

Important note

If Loop 3 is fed by an external stereo input, switching the footswitch will not bypass that source because the return is always active.

Using a TRS Splitter Cable: Turn Two Mono Pedals Into a True Stereo Return

The Parallelarator’s stereo return can accept a TRS-to-dual-TS splitter cable, allowing you to connect:

-One mono pedal to the Left return

-Another mono pedal to the Right return

Both pedals receive the same mono send (or external source), but return independently into the stereo field.

The result is a dual-mono stereo processor built from two standard pedals.

Example

• Left return → Analog delay

• Right return → Chorus

• Loop mode → Stereo

  
  

This creates rhythmic ambience on one side and modulation on the other—a complex stereo field impossible with either pedal alone.

Adding Multiple Pedals in Series Inside a Single Loop

A loop can contain multiple pedals in series, acting as a single composite effect engine.

Example: Chorus → Delay with Dry Kill Enabled

Chain inside a loop:

• Pedal 1: Chorus

• Pedal 2: Delay (dry kill ON)

  
  

Result:

• Only the delay repeats are returned (dry kill)

• Those repeats carry the chorus modulation

• The dry instrument remains clean, centred, and articulate in the main mix

  
  

This creates lush, textured ambience impossible in pure serial placement.

More possibilities

• Drive → EQ as a controllable harmonic-colour layer

• Modulation → Reverb for moving stereo ambience

• Delay → Delay for cascading rhythmic interplay

Any serial chain becomes a single wet layer, independently blended in parallel.

How Parallel Routing Unlocks Spatial Behaviour in Mono Effects

Parallel paths allow mono effects to act as stereo contributors, for example:

1. Mono Modulation

Becomes a stereo-spread layer when blended across L/R.

2. Mono Delay

Adds ambience and space without clouding the attack.

3. Parallel Tone Shaping

Compression, EQ, saturation become spatial tools when blended under the dry tone.

Example Patch: Turning a Mono Delay Into a Stereo Ambient Engine

1. Loop 1 → mono delay → Loop mode: Mono

2. Dry Mix at unity

3. Raise Loop 1 blend to taste

4. (Optional) Add modulation in Loop 2

5. (Optional) Use a TRS splitter to add a contrasting mono pedal on one side

   
   

Result: A lush, spacious stereo ambience built entirely from mono pedals.

Final Thoughts

Parallel routing unlocks the hidden spatial potential of mono pedals. With the Parallelarator, mono returns can be blended into stereo, two mono pedals can create true dual-mono stereo, entire external processors can be integrated, multiple pedals can be chained inside a loop, and Loop 3 preserves trails through intelligent switching.

The result is simple: Your mono pedals become wider, deeper, more dimensional, and more expressive — just by placing them in parallel.

Checkout Cosmic Loop FX and see what the Parallelarator can do for your rig!