MXR Carbon Copy Review — The Delay That Forgets On Purpose

Every repeat off a Carbon Copy is a little darker than the one before it. The highs roll off, the note softens, the memory gets hazier each time it comes back around — until it dissolves into the mix like it was never there. Digital delays fight to keep every repeat identical. The Carbon Copy decided that forgetting is the feature. It’s right.

The Backstory

This is 100% analog, built on bucket-brigade chips — the same technology that made delays sound like that before everything went to ones and zeros. MXR (that’s Dunlop) put it in a green box, gave it three knobs, and it quietly became the benchmark every “affordable analog delay” gets measured against. It’s been on a million boards. It’ll be on a million more.

How It Sounds

Warm, dark, and thick. The repeats sit under your dry signal instead of on top of it, so you can crank the mix and it never gets in the way of the note you actually played. Up to around 600ms of delay — enough for slapback, rockabilly, ambient washes, and that Gilmour-adjacent thing everyone tries in the guitar shop. Push the Regen and it self-oscillates into a runaway howl you can ride like an instrument.

Then there’s the Mod button. Press it and the repeats get a chorus-y warble — subtle seasickness that makes the delays feel three-dimensional. There are two trim pots inside if you want to dial the width and rate, which is MXR’s polite way of saying “we hid the good stuff, go find it.”

From the Bench

Let’s be honest about what it isn’t. No tap tempo. No presets. The delay time tops out where it tops out. And analog gear has a noise floor — this is not a silent pedal. None of that is a flaw so much as a fact: you are buying a specific dark, warm, degrading character, and if you want pristine digital repeats you are shopping in the wrong aisle. Know what you’re getting, and it’s exactly what you’re getting.

Bottom Line

The Carbon Copy is a classic because it committed to a sound and never apologized for it. It grades a 27 out of 36 — Master segment. Excellent, real strengths, easy recommend. Not higher, because the limitations are real and the modern world has tap tempo. But decades in, it still does the warm analog thing better than pedals that showed up with more features and less soul. Buy it. Let it forget.

Full disclosure: I’ve owned at least six of these. Not sequentially because they died — concurrently, because they end up on every board I build. When a pedal keeps re-earning its square inch across a dozen years and six units, that’s not nostalgia. That’s data.

Wu-Tang is for the children. Analog delay is forever.

More info: the MXR Carbon Copy Analog Delay at Jim Dunlop — straight from the maker, $159.99.