Overview:

The  FRENZEL RD-47 microphone/line tube preamp is part of our "INSPIRED" line of products.  It was inspired by the classic vintage 1959 EMI REDD47 microphone  tube preamp that was used by the Beatles to record their early albums at the Abbey Road Studio in London, England...but the RD-47 is not a clone. Control features were added that were not available on the original preamp to provide more tone and level control. Exceptional clear warm tones produced by a classic ECC83 voltage amplifier driving a  ECC83 dual triode output with rock solid level control enhanced by  power supply voltage regulation.

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Standard Features:

• Balanced XLR Input & Output Jacks isolated from chassis to eliminate eddy currents and hum.

• HI-Z Direct Input 1/4" jack high impedance instrument input on front panel.

• DC on filaments to eliminate 60 hz hum.

• Star ground system to eliminate induced current chassis noise.

• Rumble filter

• Polarity switch

• DB calibrated Boost level switch

• DB calibrated  Gain control

• Preamp tubes are ECC83  known for low noise and linearity

• Regulated power supply

• Classic Knobs and Toggle Power Switch

• Standard IEC plug-in three prong grounded power cord. 

• Rock solid point-to-point hand wiring using only the best of parts...low noise tubular polypropylenes caps, metal film resistors, Micalex sockets, Neutrik  jacks...etc.

• 2U Rackmount Chassis

• Weight - 10 lbs. 

• Dimensions - 19"W x 10"D x 3.5"H 

• Tubes:  2 - ECC83

 

FRONT PANEL:

        HI-Z DIRECT INPUT JACK

        FINE GAIN CONTROL
        VOLTAGE  DB LEVEL SWITCH
        POLARITY SWITCH
        RUMBLE FILTER SWITCH

        PILOT LIGHT
        POWER SWITCH

REAR PANEL:

        POWER CORD
        FUSE
        BALANCED XLR LOW IMPEDANCE  OUTPUT 

        HI-Z  1/4' HIGH IMPEDANCE OUTPUT JACK
        BALANCED XLR LOW IMPEDANCE  INPUT     

Specifications:

• Input Impedance: Balanced XLR 600 ohms

• Output Impedance: Balanced XLR 600 ohms & HI-Z 50,000 OHM

• Sensitivity: 5 mv

• Voltage Boost: Selectable 34 db – 40 db - 46 db

• Frequency Response: 30 -15,000 hz

• Gain Control Range: -20 db to  0 db for each Boost Level

• Polarity Control: Normal – Reverse

• Rumble Filter: On – Off

• Voltage Amplifier: ECC83

• Output Driver: ECC83

• High Voltage Regulated: High Stability and Accuracy

• Input/Output Transformers:  Balanced and Shielded For Ultra Low Noise

• Power: 120 VAC (Upgrades available for 100 – 240 VAC operation outside USA)

• Chassis: Custom 2U Ventilated Rack Mount Chassis

  

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