Rupert Neve Designs RNDI Active Transformer Direct Interface

Phantom-powered active DI with custom transformers, wide bandwith, high-headroom, and signature “Neve” tone.



12-Month Special Financing**


Rupert Neve Designs RNDI Active Direct Box featuring Class-A biased discrete FET amplifiers and custom Rupert Neve-designed transformers with game-changing headroom and signature Neve tone

One of the key design elements to the Neve signature sound, whether it’s for his classic 80-series console designs or the modern Portico II series, are Rupert Neve-designed custom transformers. The RNDI active DI box not only features a Class-A biased, discrete FET amplifier meticulously fine-tuned to work in precise harmony with the RNDI’s Rupert Neve-designed custom transformer. The result of this synergy is a unique response that does for the bass what Neve’s classic 1073 does for vocals: produce a larger-than-life, yet nuanced tone that signals to listeners that this is what a hit record is supposed to sound like. Not just for bass, the RNDI is also capable of reproducing the full harmonic depth of guitars, acoustic instruments, and professional line level sources. Plus, the RNDI can handle the full output of a 1000-watt amplifier without breaking a sweat. With roadworthy build construction and easy portability, the Rupert Neve Designs RNDI active direct box is on track to become every bit the legend for direct signals as his 1073 preamp is for tracking with microphones.

Rupert Neve Designs RNDI in one take:

  • Unique components and Neve design expertise provide groundbreaking direct tone
  • High input headroom of +21.5dBU is capable of handling professional, line-level sources without a pad
  • Speaker mode enables the RNDI to handle the full output of a 1000-watt power amplifier (92Vrms or 266Vp-p).
  • Immensely consistent performance across a wide variety of sources due to its 2M ohm discrete FET input and high headroom
  • Low-impedance transformer coupled output below 50 ohms is capable of driving long lines with unrivaled high-frequency performance
  • In instrument mode the 1/4″ Thru output can feed an amplifier input for reinforcement
  • In speaker mode, the Thru is used to feed the amplified signal to the speaker
  • Best-in-class phase coherence at all frequencies keeps the sound well-balanced and natural when blending direct signal with mic capture of the same source
  • A ground lift switch is provided on the back to help fix any problematic grounding
  • Powered by standard 48V phantom power
  • You can use the RNDI with basses, guitars, acoustic instruments, keyboards, and professional line-level devices; in instrument mode, you can even connect a professional line level interface output to “re-preamp” a previously recorded source
  • A rugged steel chassis features an industrial-grade powder coating, and is built to withstand the severe stresses of life on the road

INSIDE THE BOX—Rupert Neve Designs RNDI

Rupert Neve-designed custom transformers

The custom transformers used in the RNDI provide superior passive isolation while adding dimension and harmonic richness to the sound. Its low-impedance, transformer-balanced output excels at driving long cable runs, while maintaining consistent performance regardless of connected equipment. This is very important or both live sound reinforcement as well as large recording studios, where an unamplified signal may travel as much as 100ft before hitting an amplifier. In other designs, these high-capacitance lines cause major reductions in high frequencies. However, the output stage of the RNDI excels at handling long runs with minimal loss.

Class-A discrete FET amplifier

The RNDI’s class-A and discrete FET amplifier is powered by 48V phantom power, creating a very high impedance input of 2 megohms, which ensures consistent performance across the frequency spectrum of a wide variety of instruments. The significance of the RNDI’s Class-A design is that there is no crossover distortion added to the signal, which can add upper-order odd harmonics that are musically dissonant. With the RNDI, harmonic content is mostly 2nd order (octave) with some 3rd order present (fifth above octave). These musically relevant harmonics, present in subtle amounts, add to the richness of the original signal. The discrete nature of the RNDI’s circuit design means that there are no ICs or digital components that can degrade tone.

Rupert Neve’s effort to harmonize the performance of the transformer and the FET amplifier have resulted in an extremely well-balanced response. Low-end tonality is thick and powerful, with frequency response several octaves below audibility, ensuring phase coherence in the audible spectrum. The high end is clear, present, and smooth, with a frequency response extending beyond 100kHz. The phase coherence is unrivaled at all frequencies, which keeps the sound as natural as possible‑crucial when blending the RNDI’s direct signal with a microphone capture of the same source. Simply put, there is no DI made that performs like the RNDI.

Game-changing headroom with instrument and speaker modes

Instrument mode

In instrument mode, the RNDI’s high input headroom of +21.5dBU is capable of handling not only instruments, but professional, line level sources like interfaces, CD players and drum machines without a pad. This allows the RNDI to serve as a way to “re-preamp” any previously recorded track using your interface and a desired pre-amp. To do this, simply connect a channel output of the interface to the input of the RNDI and connect the RNDI’s output to the preamp and engage 48V. By “Re-Preamping” you can apply the tone of another preamp to the source and more accurately automate or control the drive level on the preamp.

Speaker mode

In speaker mode, the RNDI can handle the output of a 1000-watt amplifier (92Vrms or 266Vp-p) to capture the full tone of the instrument, preamplifier, EQ, inserts, and the amplifier’s output stages before it hits the speakers. This technique allows the engineer to avoid any bleed in a live environment and any unwanted tone added by the speaker cabinet or microphone. When used with modern speaker emulation plug-ins, this technique lets you take advantage of both the flexibility of digital modeling and the superior non-linear response of an actual analogue amplifier.

* Note: with tube power amps, the speaker must be connected to the Thru connection to provide a load for the amplifier

OUTSIDE THE BOX—Rupert Neve Designs RNDI

Housed in a rugged steel chassis with an industrial-grade powder coating, the front panel of the RDNI has a 1/4″ unbalanced instrument input, 1/4″ Thru, input level selector for speaker or instrument level, and an LED power indicator. The rear panel has a balanced XLRM output and a ground-lift switch.

The Rupert Neve Designs RNDI is a game-changing active direct box that is worthy of all the praise that the name “Neve” signifies in the audio industry. For more information, call or chat online with your Westlake Pro Sales Consultant today.

Rupert Neve Designs RNDI specifications:


(Measured Output, un-weighted, 22Hz-22kHz, source impedance 150 Ohms to 10K Ohms):

  • Better than -110dBV

Input Impedance

  • Instrument Setting: 2.2 Meg Ohm
  • Speaker Setting: 200k Ohm

Output Impedance

  • Less than 40 ohms

Frequency Response

  • +/- 0.25dB from 25Hz – 44kHz
  • +/- 1dB from 12.5Hz – 63kHz
  • -3dBu @ 92kHz

Maximum Input Level

  • Instrument = +21dBu Typical Speaker = +41.5dBu, 92Vrms (266Vp-p)

Maximum Output Level

  • +11.5dBu output at maximum input level

Total Harmonic Distortion plus Noise (THD+N)

  • @ 1kHz, +20dBu input level:
    0.25% Typical (2nd and 3rd harmonic)
  • @ 1kHz, -20dBu input level :
    0.015% Typical (2nd and 3rd harmonic)
  • @ 20Hz, -20dBu input level :
    0.75% Typical (2nd and 3rd harmonic)

Power Requirements

  • Phantom power, 4.5mA @ +48VDC


  • 1.5 lb.


  • 6-1/4″ x 4″ x 1-1/2″ (L x W x H)

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