Rupert Neve Designs RNDI-M | Active DI-Box

The Rupert Neve Designs RNDI-M is an active direct box with transformer-coupled output stage, developed for professional applications at the highest sonic level. It combines the proven sound design of the successful RNDI in a particularly compact form factor that is ideal for pedalboards, mobile setups or studio use where space is limited. The underlying circuitry is based entirely on discrete components and integrates the specially wound Rupert Neve Designs output transformer, which guarantees outstanding isolation, musical overtones and stable performance over long cable runs.

The Class A FET input stage of the RNDI-M is equipped with a high input impedance of 2.2 MOhm and is operated via standardized +48V phantom power. With an input headroom of +20.5 dBu, the DI box processes a wide range of signal sources – from electric guitars and basses, synthesizers, keyboards and drum machines to line signals and pre-produced material. The internal design completely dispenses with integrated circuits (ICs) or digital components to ensure maximum sound purity.

In the frequency range, the RNDI-M demonstrates exceptional linearity: the transmission range extends from 28 Hz to 60 kHz within ±0.25 dB and remains stable up to 90 kHz within ±1 dB. This ensures precise reproduction of all the nuances of the input signal – from powerful low bass to detailed mids and brilliant highs. The harmonic structure is primarily characterized by musically relevant second and third order harmonics, which lend the sound a pleasant depth and warmth.

The housing is made of robust steel and is designed for intensive use in the studio and on stage. A ground lift switch ensures effective ground isolation in the event of potential grounding problems, while the THRU output allows the input signal to be looped through to an amplifier or other devices without loss. The transformer-balanced output (less than 40 ohms impedance) allows low-loss signal transmission even over very long cable runs – an important feature for professional live or recording environments.