Rotel RD-850 cassette deck

RD850 is a full-feature cassette deck which makes quality tape recording easy and dlivers excellent sound reproduction from pre-recorded tapes

Incorporating Dolby C noise reduction,RD850 provides a Signal-to-Noise Ratio of 72 dB for virtually noise-free recording and playback. To make RD850 compatible with a wide range of pre-recorded tapes. Dolby B is also included. Bias settings for normal, chrome or chrome-equivalent, and metal tapes give flexibility in your choice of tape formulations. LED record-level meters and soft-touch controls make RD850 a pleasure to use. A microphone input is included for live recording.

Technical refinements include a precision tape transpport mechanism for accurate, transparent sound reproduction from all your favourite cassettes. An electronically controlled high-torque DC motor minimizes Wow and Flutter. To maintain optimum distortion-free musical reproduction. RD850 uses a Sendust record/play head. Exceptionally hard, durable and ideally suited to recording and playback applications. Sendust is the material of choice for high-performance cassette decks and gives RD850 an extra dimension of quality and musiclity.

Like all components in the critically acclaimed Rotel line, RD850 emphasizes performance, reliability, ease of use and attractive styling. It is an excellent complement to other models in the Rotel hi-fi range of quality audio equipment and represents outstanding value .

Dolby Noise Reduction

A severely limited Signal-to-Noise Ratio (in the 50 to 55 dB range with perhaps a 10 dB peak) has always been an inherent weakness of the cassette format. While the dynamic range of most live music lies in the area of 70 dB to 80 dB, cassettes with no noise reduction are capable of a 65 dB dynamic range at best.

Dolby B was a dramatic breakthrough in increasing dynamic range by lowering the noise threshold by up to 10 dB in upper frequencies (where tape hiss is concentrated). With the advent of Dolby C, a 20 dB improvement in Signal-to-Noise Ratio is possible, with NR extending a full two octaves beyond the range covered by Dolby B, and Dolby C delivers much more stable and accurate  response in the higher frequency ranges while eliminating harmonic distortion.

RD850 incorporates Dolby C NR to give you the full benefit of these significant developments. Dolby B is included to make RD850 compatible with the everincreasing library of pre-recorded tapes encoded using this system.

 

Specifications

System:  4-track, 2 -channel

Motor:  Electronic DC Governor

Heads:

Rec/Play :  Sendust Guard head

Erase :  Ferrite core

Tape Speed:  4,8 cm/sec

Wow and Flutter:  0,2% (DIN);  0,08% (WRMS)

Total Harmonic Distortion (Rec/Power Bandwidth, 400 Hz):  1,0% (Metal)

Frequency Response:

Normal, LH Tape :  30 to 17,000  Hz ±3 dB

Special Tape :  30 to 17,000 Hz ±3 dB

Metal Tape :  30 to 18,000 Hz ±3 dB

Signal-to-Noise Ratio (WTD 0 dB =580 mV, Chromium):

Dolby NR In :  64 dB (B type);  72 dB (C type)

Dolby NR Out :  55 dB

Input Sensitivity/Impedance:

Mic :  0,3 mV/10 k Ω

Line :  58 mV/33 k Ω

Output Level/Impedance

Line :  580 mV/1 k Ω

Fast Wind Time (C-60):  90 sec.

Tape Selector

Normal, LH :  100% (BIAS);  120 µs (EQ)

Special :  150% (BIAS);  70 µs (EQ)

Metal :  220% (BIAS);  70 µs (EQ)

Power Requirements:  120V, 220 V, 240 V, 50/60 Hz

Power Consumption:  22 watts

Dimensions (W x H x D):  430 x 117 x 270 mm (16-15/16" x 4-5/8" x 10-5/8")

Weight:  3,9 kg (8,58 lbs)