The Alexander Pedals Syntax Error XP is a digital glitch pedal, described by its maker as a "dialup modem simulator" and an audio transformation platform for guitar, bass, keys or whatever else you plug into it1. Where most multi-effects pedals aim to polish your tone, this one aims to break it: bit-crushing, sample-rate reduction, ring modulation, frequency shifting and pitch mangling, all inspired by the 8-bit sounds of early videogames and failing late-90s computers. Alexander Pedals puts it bluntly: "Your tone has never sounded more like a Gateway 2000 slowly dying. The Y2K bug didn't destroy civilization, but this pedal will destroy your clean signal at 56k baud."1
The XP is the Leap Series version of the Syntax Error: Alexander Pedals took their glitch pedal, put it in a smaller enclosure, and added more ways to break your signal2. As of late October 2026 it is listed as Sold Out on the maker's page at $249.991.
The eight sound modes
The XP features eight sound modes, each with its own set of tweakable parameters1. The maker and press name several of them directly:
| Mode | What it does |
|---|---|
| RING | Ring modulator from tremolo to gonging robot sounds, with a sample & hold that randomizes the carrier1 |
| CUBE | Digital distortion via math, paired with a resonant filter, from subtle grit to genuine destruction1 |
| FREQ | Frequency shifter (not a pitch shifter) applying a fixed Hz offset: phaser-like tones, cascading echoes, or out-of-tune sounds depending on feedback1 |
| WAVE | FM-style modulation warping your signal's frequency, between vibrato and clangy percussive metal1 |
| GLITCH SHIFT | Pitch shifting with the safety rails removed, plus a BARF control that introduces artifacts1 |
| Stretch | Varispeed timestretch, sampling your playing and mangling it like a dying tape machine2 |
| Dynamic | Bit-crushes and sample-rate reduces2 |
Delicious Audio's reviewer, Brent P. Gladless, described Freq as a mode that "frequency-shifts without preserving intervals, bubble sounds, gargle sounds, random modulation that occasionally lands on something musical"2, and noted that Cube runs on an algorithm involving the absolute value of the input cubed times three, plus a resonant low-pass filter2.
Presets, LFO, RAMP and expression control
The pedal stores 32 user presets, arranged in 4 banks of 81. Hold the Bypass / Preset footswitch to select the next preset, or hold both footswitches for the previous one1.
Beyond presets, the XP adds movement:
- An assignable LFO modulation system for parameter automation1
- Expression control that morphs between settings2
- A RAMP function that, in the reviewer's words, "turns the whole thing into an LFO, cycling between two sounds indefinitely, phasing, moving, never sitting still"2
The MultiJack on the pedal handles expression pedal, foot switch, or MIDI input, so an expression pedal or a MIDI controller can drive those morphs12.
Power and connections: 9V, 250mA isolated
The XP runs on DC 9V only and draws 250mA or greater, and it requires an isolated DC power supply1. That rules out a battery and makes a shared daisy chain a bad idea; plan on a spot on an isolated power brick.
The XP needs an isolated 9V supply rated for at least 250mA. It will not run on a battery, and sharing a non-isolated daisy chain with other pedals goes against the maker's power requirement1.
Connections are flexible: the input jack is selectable for standard mono or TRS stereo signal input without opening the pedal, and the output jacks are usable as either mono, two-cable stereo, or TRS stereo, with stereo audio input and output and phase correction1. The original Syntax Error, by comparison, drew 80mA at 9V DC center negative3, so the XP is a much hungrier pedal than its ancestor.
A smaller Leap Series version of the Syntax Error
The Syntax Error line goes back to 2017, when the original launched as part of Alexander's Neo Series of compact effects, an "Arcade Game" style pedal inspired by 8-bit videogame sounds with modes including Stretch, Cube, Ring and Freq, plus a Code mode34. Gearnews reviewed it then as a buffered bypass unit that "will take your guitar to places that you just wouldn't get anywhere near with a" conventional pedal, with a Sample knob that messes with the internal sampling rate down to 8-bit style sampling, and a Mix knob for the effected level4.
In October 2021, first shown at Summer NAMM 2021, Alexander Pedals released the Syntax Error 2: twice as wide as the original, an arcade-game-inspired digital pedal with six sound modes (STRETCH, AIR, RING, CLUBE, FREQ, WAVE) for guitar, bass, keys or other instruments56. It was the first product Matthew from Alexander Pedals designed using the FXCore DSP6, with advanced stereo routing selectable as Mono, Stereo Summing, or Stereo in a global configuration menu5, buffered hybrid analog+digital bypass5, and full MIDI control of every knob and setting via the MultiJack with Neo Link, directly to any Disaster Area Gen3 controller, or through a USB MIDI port to a computer or mobile device5.
The XP then shrank the concept into the Leap Series enclosure: same digital chaos, smaller box, now with stereo ins and outs, 32 presets, the LFO system and MIDI over the MultiJack1.
What reviewers said
Delicious Audio's February 2026 review by Brent P. Gladless found the XP rewarding but demanding. On usability, the review reports that forum users call it a "WTF is that" pedal, that its sweet spots are fractions of a degree wide, and that it is not plug-and-play but aimed at sonic anarchists2. On character:
"It's not a tool. It's a collaborator with impulse control issues."
Brent P. Gladless, Delicious Audio2
The review says the pedal evokes dirty game cartridges, dial-up handshakes and early digital failing, and notes one reliability quirk: Stretch mode's buffer length sometimes randomizes on preset recall, so a three-second delay can become 300 milliseconds without warning2. The pedal is made in North Carolina2.
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Questions
Is the Syntax Error XP true bypass?
No. Alexander Pedals specifies a buffered bypass for the Syntax Error XP, the same approach as the earlier Syntax Error and Syntax Error 2. A buffered pedal still passes your clean signal when switched off, and it drives long cable runs, but it is not a hard-wire true bypass.
Does the Syntax Error XP work in stereo?
Yes. It has stereo audio input and output with phase correction. The input jack is switchable between standard mono and TRS stereo without opening the pedal, and the output jacks work as mono, two-cable stereo, or TRS stereo.
Can I control the Syntax Error XP with MIDI?
Yes. The pedal takes MIDI through its MultiJack, the same jack used for an expression pedal or a foot switch. On the related Syntax Error 2, every knob and setting is controllable over MIDI, either through the Neo Link adapter, a Disaster Area Gen3 controller, or the USB MIDI port.
What is the difference between the Syntax Error and the Syntax Error XP?
The XP is a smaller Leap Series version of the original Syntax Error, with stereo ins and outs, 32 presets, an assignable LFO system and eight sound modes instead of the original's smaller set. The Syntax Error 2, released in October 2021, is a larger pedal with six modes and the FXCore DSP.
Does the Syntax Error XP work on bass and keys?
Yes. Alexander Pedals describes it as an audio transformation platform for guitar, bass, keys or whatever else you plug in, and the maker's copy for the line invites you to build your own arcade soundtrack with any instrument.
Is the Syntax Error XP still available?
As of late October 2026 the pedal is listed as Sold Out on the Alexander Pedals product page at $249.99. The manual and firmware remain available from the maker's support page, so check with dealers for remaining stock.
Sources (6)
- Alexander Pedals Syntax Error XP Dialup Modem Simulator, Alexander Pedals
- Alexander Pedals Error XP Multi-FX Pedal, Delicious Audio, 2026-02-26
- Syntax Error by Alexander Pedals, RockBoard PedalPedia, 2026
- Alexander Pedals Syntax Error: A crazy glitch pedal from the 80s dial-up era, gearnews.com, 2017-07-24
- Syntax Error 2, Alexander Pedals
- Alexander Pedals Syntax Error 2, Delicious Audio, 2023-04-20
