Caroline Guitar Co. Caroline Parabola

The Caroline Parabola is a solid state tremolo pedal from Caroline Guitar Co., a small batch builder in Columbia, South Carolina. Caroline positions it as your rig's new "tremolo channel": an amp-style tremolo that sits in the signal chain the way a tremolo channel on an amplifier would¹. Delicious Audio introduced it in April 2018 as the company's latest pedal².

What sets the Parabola apart from a basic tremolo is that it offers two modulation flavors and gain on both sides of the effect. You get the classic, dramatic amplitude modulation (AM) you might expect, or a filtered modulation (FM) that Caroline describes as subtle, beautiful, and less invasive on your playing³. Around the modulation sit pre and post effect gain stages for both overdrive and volume boost³.

AM and FM: the two tremolo modes

The AM mode is the familiar tremolo sound: the signal's amplitude swings up and down at the speed you set, giving the classic, dramatic amplitude modulation most players expect from the effect³.

The FM mode works differently. Instead of modulating volume, it modulates a filter, which Caroline says makes it subtle, beautiful, and less invasive on your playing¹. For a player, that means the effect sits under the notes rather than chopping them, useful when you want movement in the sound without the pulsing volume dip of a standard tremolo.

Guitar Pedal X's reviewer compared the two directly on the Pawnshop Edition:

Stefan Karlsson, Guitar Pedal X⁴

He also noted a preference caveat: while calling it "a beautifully simple and elegant tremolo," he "would possibly have preferred Harmonic as the second mode"⁴. That is a matter of taste rather than a fault with the pedal, but it is worth knowing that the second mode here is a filtered tremolo rather than the harmonic (pitch-shifting) tremolo found on some other designs.

Controls and gain stages

The control set, as documented on the Pawnshop Edition by Guitar Pedal X, is straightforward⁴:

The Pawnshop Edition also adds a Havoc footswitch for maximum Depth and Speed, momentarily slamming both controls to their extremes for a dramatic effect⁴.

The gain stages are the other half of the pedal's character. Caroline added pre and post effect gain stages for both overdrive and volume boost³. In practice, the pre gain pushes the signal into the modulation stage harder, which can drive the circuit into overdrive, while the post gain sets the output level as a boost. This is what lets the Parabola do double duty as a tremolo and as a boost or light overdrive pedal.

History and versions

Caroline lists the Parabola in two versions: Standard and Pawnshop³. The pedal arrived in 2017 in an unexpected way. Philippe, the company's co-founder, had felt compelled to try building a phaser in 2017, "but we made Parabola™ instead"⁵. Delicious Audio described the resulting pedal in April 2018 as the "gentle dip into modulation" that Philippe had spoken of during a Reddit AMA the previous October².

The circuit itself has a borrowed heart. Caroline adapted the "deliciously sloshy, transistor-based LFO and distinctive waveform" from what RockBoard's PedalPedia calls its favorite "West German" device, with modified speed and depth¹².

The Pawnshop Edition is a special edition of the Parabola that is long since sold out on the Caroline Guitar site, with a handful of units remaining on Reverb.com⁴. Where the standard Parabola's FM mode offers what the maker calls "a filtered modulation (FM) that is subtle, beautiful, and less invasive on your playing," Philippe described the pedal's modulation side as a "gentle dip into modulation" during a Reddit AMA in October².

Among Caroline's modulation pedals, the Pawnshop Parabola earned a strong placing from Guitar Pedal X's reviewer, who ranked it second of the three Caroline modulations he owned, behind the Arigato and ahead of the Somersault⁶.

Videos

Click to load

Click to load

Click to load