Rupert Neve Designs RNDI-S Two Channel Active Transformer Direct Interface Owner’s Manual

RNDI-S Two Channel Active Transformer Direct Interface

“

Product Specifications

• Noise (22Hz – 22kHz, Un-weighted): Better than -110dBV
• Input Impedance (ZIN) Instrument Input: 2.2 Megohm
• Input Impedance (ZIN) 3.5mm Input: 95 Kilohm
• Output Impedance (Z ) OUT: Less than 40 Ohm
• Frequency Response: 28 Hz – 60 kHz (+/- 0.25 dB), 14 Hz – 90
  kHz (+/- 1dB -3dB)
• Maximum Input Level Instrument Input: +20.5 dBu (8.2 Volts RMS)
  Typical
• Maximum Output Level: +11.5 dBu Typical
• Total Harmonic Distortion + Noise:
  • @ 1 kHz, +20 dBu Input Level: 0.25% Typical (2nd and 3rd
    Harmonic)
  • @ 1 kHz, -20 dBu Input Level: 0.015% Typical (2nd and 3rd
    Harmonic)
  • @ 20 Hz, -20 dBu Input Level: 0.75% Typical (2nd and 3rd
    Harmonic)
• Power Requirements: 4.5mA Per Channel @ +48VDC
• Mounting Option: 19 Rack Shelf Mounting Option, 4 hole pattern
  (bottom of unit) for 6-32 machine screws
• Weights & Dimensions:
  • Product Dimensions (D x W x H): 7″ x 5″ x 1.75″
  • Shipping Dimensions (L x W x H): 10″ x 8″ x 3″
  • Shipping Weight: 3 lbs (1.36 kg)

Product Usage Instructions

Front Panel Features:

• Instrument Input: Accepts a standard instrument cable for
  connecting your instrument.
• 48V Power Switch: Turns on the phantom power for the
  channel.

Rear Panel Features:

• Parallel Outputs: Provides parallel outputs for connecting to
  multiple devices.
• Instrument Input Z2: Another input option with a different
  impedance.

Usage Steps:

1. Connect your instrument to the Instrument Input on the front
   panel using a standard cable.
2. If needed, engage the +48VDC phantom power by flipping the
   switch on the front panel.
3. Adjust input and output levels as needed based on your audio
   setup.
4. If connecting to multiple devices, utilize the parallel outputs
   on the rear panel.

Frequently Asked Questions (FAQ)

Q: What is the purpose of the LIFT and GND switches on the rear
panel?

A: The LIFT switch helps eliminate ground loops by isolating the
ground, while the GND switch can be used to provide a ground
connection when needed.

“`

RNDI-S
Two Channel Active Transformer Direct Interface

RNDI-S Specifications
Note: All Specifications are typical
Noise (22Hz – 22kHz, Un-weighted)
Input Impedance (ZIN) Instrument Input 3.5mm Input
Output Impedance (Z ) OUT
Frequency Response +/- 0.25 dB +/- 1dB -3dB
Maximum Input Level Instrument Input
Maximum Output Level Total Harmonic Distortion + Noise
@ 1 kHz, +20 dBu Input Level @ 1 kHz, -20 dBu Input Level @ 20 Hz, -20 dBu Input Level
Power Requirements Mounting Option
Weights & Dimensions Product Dimensions (D x W x H) Shipping Dimensions (L x W x H) Shipping Weight

Better than -110dBV
2.2 Megohm 95 Kilohm
Less than 40 Ohm
28 Hz – 60 kHz 14 Hz – 90 kHz
Below 5 Hz
+20.5 dBu (8.2 Volts RMS) Typical
+11.5 dBu Typical
0.25% Typical (2nd and 3rd Harmonic) 0.015% Typical (2nd and 3rd Harmonic)
0.75% Typical (2nd and 3rd Harmonic) 4.5mA Per Channel @ +48VDC 19″ Rack Shelf Mounting Option
4 hole pattern (bottom of unit) for 6-32 machine screws
7″ (17.78 cm) x 5″ (12.7 cm) x 1.75″ (4.45 cm) 10″ (25.4 cm) x 8″ (20.32 cm) x 3″ (7.62 cm)
3 lbs (1.36 kg)

Front Panel Rear Panel

4488VVCPHow1 Peor w(CeHr 1) PInodwiceartesstawtuhesnLE+D48fVoDr CCHis1 present on the channel

11//44″” CTHHR1UTh(rCuH 1) PPaarraalllleell11/4/4″ “jajackckused tdusoiisgresenedcantlltdyotottosheaeannnidnaapmmutppsliifgienral

33..55mmmmIInnppuutt SStteerreeoo UUnnbbaalalanncceeddInInpuptut 9CZC5iHHn =k119-=5TInTikpipp, uC, tCHIHm22p=e=RdiRnaignncge

11//44″” CINH(2CIHns2tr)ument Input HUin-bZaUlannbcealdanIncpeudt Input 2Z.IN2=M2.2IMnput Impedance

Rupert Neve Designs

IN

1 THRU

48V

POWER

INPUTS
3.5MM
1/4″

IN
48V POWER

2 THRU

11//44″” ICNH(1CIHns1t)rument Input UHni-bZaUlannbceadlaInncpeudt Input Z2I.N2=M2.2 IMnput Impedance
CGHN2DGLrIoFuTn(dCHLif2t ) ISswoiltacthesthCaHt li2ftsXXLRLRPiPnin11 ffrroommcgirrcouuitngdround

ISISbNneewpltPiewtucUcethtTesStnSh1eat/lhe4t etc”otI1ng/4gp”lueatsnd o3.r53m.5mmInmpuIntsput

48V Power (CH 2) I4n8dVicaCtHes2wPhoewn +e4r8VDC is pProewseenrtsotantuthseLcEhDanfonreCl H 2

GCHN1DGLrIoFuTn(dCHLif1t) SIswoiltacthesthCaHt li1ftsXXLRLRPiPnin11 ffrroommcgirrcouuitngdround

11//44″” CTHHR2UTh(rCuH 2) PPtoaarrsaaellnlleedll1t1/h4/e4″ “ijnajapcckuktususiegsedndalto sdeirnedctlsyigtonaalntoamapnliafimerp

RNDI-S
Active Transformer Direct Interface
LIFT

OUTPUT 2

GND
Rupert Neve Designs, LLC

OUTPUT 1
LIFT GND
Made in USA

OCHU2TPOUuTtp2ut XTrLaRnDsfIoOrmuteprubt uatlialinzicnegdcustom RXNLRDOTruatnpsufot.rmer
ZImOUpT e<d4a0nce < 40

OCHU1TPOUuTtp1ut XTrLaRnDsfIoOrmuteprutbuatlialinzicnegdcustom RXNLRD OTruatnpsufotr. mer
ZImOUpT <ed4a0nce < 40

RNDI-S Overview
The RNDI-S is designed to provide instrument (electric guitar, bass, keyboard, piezo pickup, etc.) direct injection. The discrete Class-A circuit topology found in the RNDI-S is based around Mr. Rupert Neve’s custom transformers, allowing for outstanding sonic performance and excellent noise rejection. The RNDI-S can handle extremely high input levels without clipping (up to +20.5 dBu), and the transformer-coupled output has a low impedance of less than 40 Ohms, thereby allowing the RNDI-S to drive long lines with minimal loss. The RNDI-S chassis is a formed steel “clamshell” construction designed to stand up to the rigors of stage and studio use.
Usage Notes
Power needs to be supplied independently to both channels of the RNDI-S by standard 48V Phantom Power via the XLR output connectors. 48V Power Status is indicated by two independent front panel LEDs. Avoid placing this direct box near strong electromagnetic fields (such as those radiated by power amplifiers) to reduce any chance of picking up noise. If there is noticeable hum on the RNDI-S outputs, try switching the RNDI-S ground lifts as well as ground lifts on other devices in the signal chain. If this doesn’t alleviate the issue, remove individual devices from the same power circuit to isolate the source of the problem.
The RNDI-S has two available sets of inputs: the 1/4″ unbalanced instrument jacks and the 3.5mm Stereo unbalanced jack. A front panel switch selects the 1/4″ instrument jack or the 3.5mm jack input. In the instrument jack configuration, the DI converts the impedance of the instrument signal, balances the signal, and provides a buffered output to send to a separate mic preamp. In addition, the 1/4″ THRU jack is available to connect the RNDI-S to an amplifier. To guarantee the best performance, we recommend utilizing the best available cables and mic preamps.
The 3.5 mm Stereo unbalanced jack is available for 3.5mm stereo sources, which connects the left channel (Tip) to CH 1 and the right channel (Ring) to CH 2. 3.5mm sources will surely benefit from the balancing functionality included in the RNDI-S.

User Guide P/N: 775-00032 Rev. B

Documents / Resources

Rupert Neve Designs RNDI-S Two Channel Active Transformer Direct Interface [pdf] Owner's Manual RNDI-S, RNDI-S Two Channel Active Transformer Direct Interface, Two Channel Active Transformer Direct Interface, Active Transformer Direct Interface, Transformer Direct Interface, Direct Interface

References

• User Manual