NAD 7020 User manual

7020 Stereo Receiver
Date of manufacture : ? - Jan 83
Please note that this document contains the text from the original product brochure, and some technical statements may now be out of date
The NAD 7020 receiver is logically designed for optimum performance and ease of operation at an
economical price. An unusually high proportion of its cost is devoted to circuit engineering and
electronic parts rather than to elaborate styling, seldom-used controls or esoteric features. This results in
a sound quality equal to many of the finest sepa-rate audiophile components.
Every circuit in the 7020 is tested to deliver its full per-formance in everyday use, not just under
controlled labora-tory conditions. Competing products may have similar power and THD ratings, but in
actual use the 7020 is typi-cally easier to tune, less prone to background noise with either FM or phono,
and when connected to the most de-manding loudspeakers, better able to reproduce the full impact
and tonal richness of live music. The 7020 receiver produces volume levels far greater than would be
expected from its conservative 20-watt per channel power rating, due to the high-voltage, high-current
output stage and unique “Soft Clipping”™ circuit. Recent dramatic advances in FM tuner technology
have been incorporated in the 7020 as well, for especially high sensitivity, wide stereo separation and
low distortion.
STATE-OF-THE-ART CIRCUITRY
Wide-range Phono Preamplifier. Instead of the economy preamp circuit often found in budget-priced
receivers, the NAD 7020 contains a sophisticated 6-transistor phono Advanced Tuner IC Circuitry. The
7020’s FM tuner section employs a junction FET “front end” for sensitive tuning of weak signals; a total
of three (rather than one or two) ceramic I.F. filters for sharp selectivity, cleanly separat-ing adjacent
stations on the crowded FM dial; and the latest PLL multiplex decoder for wide stereo separation with
low distortion. FM reception in direct comparisons has proven to be audibly identical, in both sensitivity
and sound quality, to many costlier separate tuners. Yet it is very easy to tune: a set of three LED lights
indicate exact tuning and signal strength. The 7020’s AM reception, aided by an adjustable ferrite rod
aerial, provides good suppression of static and adjacent channel interference.
EFFECTIVE CONTROL FEATURES
Like every other part of its design, the NAD 7020’s controls have been carefully selected for genuine
usefulness. The preamp stage which is audibly identical to some of the best separate preamps. Its
distortion is extremely low even with complex music signals, it is quiet enough for use with either
moving-magnet or high-output moving-coil pickup car-tridges, and its 107 dB dynamic range is ample
for the digitally-mastered recordings of the 1980s.
High-Voltage, High-Current Output Stage
It’s not difficult to design an amplifier to deliver 20 watts/channel to an 8-ohm test resistor. But real
loudspeaker impedances are usually lower than 8 ohms and “reactive”, requiring greater reserves of
voltage and current in the amplifier. The NAD 7020 employs a high-current power supply and the same
rugged output transistors found in many “60-watt” receivers, so it is able to drive any speaker
impedance (even as low as 2 ohms) to high levels with low distortion.

Soft Clipping™
When the 7020 is overdriven beyond its rated power, this exclusive NAD circuit gently limits the
waveform voltage, ensuring that the output transistors are never driven into saturation or “hard
clipping”. Conse-quently the 7020 can produce remarkably high peak volume levels without sounding
harsh or distorted.
Infrasonic and Ultrasonic Filters
In everyday listen-ing, audio signals often are contaminated with interference at frequencies below and
above the range audible to the ear - turntable rumble, acoustic feedback, and radio inter-ference for
example. The 7020 strips off this interference so that only clean musical waveforms are amplified. Bass
and Treble controls are tailored for musically effective response in the high and low frequencies without
altering the critical mid-range tonal balance. For listening at low volume levels or with sensitive head-
phones, the 7020’s Audio Muting switch expands the useful range of the Volume control and subdues
any residual circuit noise.
Separate “Preamp Out” and “Power Amp In” jacks are provided on the rear panel of the 7020 for
insertion of an equalizer, dynamic range expander or time-delay unit. For the student or first-time stereo
shopper, the “no-frills” design and moderate price make the NAD 7020 an ideal choice; for the music-
lover seeking uncompromised per-formance, few receivers at any price will sound as good in everyday
use.

PRE-AMP SECTION
Phono input
Input impedance (R and C) 47kΩ/ 47pF
Input sensitivity, 1kHz 2.5mV ref. 20W
Signal/Noise ratio (A-weighted with cartridge connected) 75dB ref. 5mV
THD (20Hz - 20kHz) <0.02%
Line level inputs
Signal/Noise ratio (A-weighted ref 1W) 86dB
Frequency response (20Hz - 20kHz) ±0.5dB
Infrasonic filter -3db at 15Hz, 24dB/octave
POWER AMP SECTION
Continuous output power into 8Ω* 20W (13dBW)
Rated distortion (THD 20Hz - 20kHz) 0.02%
IHF Dynamic headroom at 8Ω+3dB
IHF dynamic power (maximum short term power per channel) 8Ω40W
4Ω58W
2Ω72W
FM TUNER SECTION
Input sensitivity Mono -30dB THD+N 10.8dBf (1.9µV)
Stereo 50dB S/N 16dBf (3.5µV)
Stereo 60dB S/N 37dBf (40µV)
Selectivity, alternate channel 65dB
Harmonic distortion Mono 0.2%
Stereo 0.3%
Signal/Noise ratio Mono 75dB
Stereo 70dB
Frequency response ±0.5dB 30Hz - 15kHz
Channel separation at 1kHz 42dB
AM TUNER SECTION
Usable sensitivity 250µV
Image rejection 50dB
Remote No
NAD Link No
PHYSICAL SPECIFICATIONS
Dimensions (W x H x D) 420 x 119 x 240mm
Net weight 6.8kg
Shipping weight 8.4kg
* Minimum power per chnnel, 20Hz - 20kHz, both channels driven with no more than rated distiortion.
Dimensions are of unit’s cabinet without attached feet; add up to 18mm for total height.
Dimension depth excludes terminals, sockets, controls and buttons.
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