Radial Reamp JCR Passive Studio Reamp Box

Radial Reamp JCR: The Original Reamp, Now Passive and Precise

The Radial Reamp JCR is a 100% passive studio reamping box, built around a custom US-made transformer and the original John Cuniberti Reamp design. It takes a recorded line-level track played back from your interface and steps it down to the level and impedance a guitar amp expects, sending it out a 1/4-inch jack to a real amplifier or pedalboard. For the producer who refuses to lock in an amp tone while tracking, it is the box that lets a dry take become any sound, at any time.

What Reamping Is and Why the JCR Does It Passively

Reamping is a studio technique that separates the performance from the tone. First you record a clean, dry DI track of a guitar or bass with no amp involved; later, at mixdown, you play that track back out through a reamper into a real amp or pedalboard and record the result. The catch is that an interface outputs a hot, low-impedance line signal, while an amp expects a weak, high-impedance instrument signal. The Reamp JCR resolves that mismatch entirely with a passive transformer that steps the level down and raises the impedance to what a pickup would present, so the amp reacts exactly as it would to a guitar plugged straight in. Being passive, it needs no power and adds no active noise to the path.

A Custom US-Made Transformer at the Core

The transformer is the whole instrument here, and Radial builds a custom US-made unit for the JCR. It carries a full 20 Hz to 20 kHz response within one decibel, so no part of the guitar's range is lost on the way to the amp, and it delivers an enormous 140 dB dynamic range that handles transients without strain. Because the conversion is done by iron rather than active circuitry, the reamped signal takes on the natural warmth and gentle saturation a good transformer adds, part of why the original Reamp became a studio standard.

Variable Level and a 3-Position Filter

Getting a reamp to sit right takes control over drive and tone. A variable level control sets exactly how hard the signal hits the amp's front end, from a clean edge-of-breakup push to a fully cranked, saturated shove, without touching the recording. A three-position filter then shapes the feed with a high-pass to tighten flubby low end, a low-pass to tame harsh highs, or a flat bypass, letting you pre-shape the signal before it ever reaches the amplifier.

Polarity, Ground Lift, and a Mute Switch

Studio integration lives in the details. A 180-degree polarity reverse keeps the reamped signal phase-aligned with your other tracks, and a ground lift breaks the hum loops that appear when an interface and a guitar amp share the same power. A mute switch silences the output so you can safely re-patch amps, swap pedals, or move cables without a loud pop through the speaker, which protects both the amp and your ears between takes.

TRS and XLR Inputs, 1/4-Inch Amp Output

The Reamp JCR accepts a signal however your interface delivers it. A 1/4-inch TRS input takes a balanced or unbalanced line output, and an XLR input handles a balanced feed from a console or converter, with a maximum input of +26 dBu so even hot playback levels stay clean. A single 1/4-inch unbalanced output then runs to the amplifier's instrument input, presenting a 1.8 kilohm input and 4.8 kilohm output impedance carefully chosen to mimic a real pickup.

Fully Passive, Housed in 14-Gauge Steel

Because every conversion happens in the transformer, the Reamp JCR needs no power supply, battery, or phantom power, one less thing to fail in the middle of a session. The chassis is folded from 14-gauge steel in Radial's signature blue, with the book-end design that shrugs off the knocks of a busy studio. Set it on the desk, patch it once, and it simply works, session after session.

Where the Reamp JCR Fits Your Workflow

The core use is to record a dry DI now and dial the amp tone later, freeing you to commit to the perfect take and audition amps against a finished mix. Because the performance is banked, you can experiment endlessly with amps, pedals, and mic placements without asking a player to perform again. The JCR also opens creative doors beyond guitar: send drums, synths, or vocals back out through guitar pedals and amps to add grit and character. Any time you want to shape tone with real hardware after the performance is done, the JCR is the send.