7140 Stereo Receiver
Date of manufacture : Jan 87 - Nov 89
Please note that this document contains the text from the original product brochure, and some technical statements may now be out of date
NAD is internationally recognised as the value leader in Hi-Fi, and the new 7140 stereo receiver provides
an exceptional ratio of performance to price (even by NAD standards).
The tuner section of the 7140 combines the convenience and accuracy of digital frequency-synthesis
tuning with superior stereo sensitivity and quieting.
The phono preamplifier, too, is audibly (and in some cases dramatically) quieter than many other preamp
circuits, not only with moving-magnet pickups but also with low-output moving coil cartridges. The
entire amplifier circuit has ample dynamic range for every program source, including the widest-range
digital Compact Discs.
The powerful high-current output stage of the 7140 drives loudspeakers to surprisingly high volume
levels with clean, solid, full-bodied musical sound and a refreshing freedom from distortion, even in
transient peaks. The exclusive NAD impedance selector allows you to make maximum use of the
amplifier’s power regardless of the true impedance of your speakers.
The 7140 is conservatively rated at 40 watts/channel in the normal stereo mode, not only with test
resistors but with loudspeakers of any impedance. Its 3 dB of IHF Dynamic Headroom means that it will
deliver fully double its rated power (over 80 watts per channel) in brief bursts, important for undistorted
reproduction of the uncompressed transients in Compact Discs and DBX-encoded recordings.
Digital-ready design
The receiver’s line-level inputs will not be overloaded by high-level signal peaks from a Compact Disc
player or digital tape recorder. The 102 dB signal-to-noise ratio of the 7140 exceeds that of any
analogue or digital program source. The low-impedance, low-noise design of the volume and tone
control circuits guarantees that the transparent clarity of the finest analogue and digital recordings will
be preserved.
Low-noise MM/MC phono preamplifier
The phono preamplifier in the 7140 is a discrete (non-IC) design featuring a matched pair of extremely
low-noise transistors in a differential input circuit. It interfaces correctly with the impedance of magnetic
cartridges, and a rear-panel MM/MC selector increases the circuit gain by 20 dB for low-output moving-
coil pickups. The preamp has a push-pull output circuit, like a miniature power amplifier, that provides
ample current to drive the precision RIAA equalisation network without slewing distortion, and its large
dynamic range (107 dB) comfortably accommodates all digitally-mastered LP recordings with room to
spare.
As long as LPs remain a principal music source for many listeners, there must be no compromise in the
quality of the phono preamp circuit.
Download from Www.Somanuals.com. All Manuals Search And Download.
PRE-AMP SECTION
Phono input
Input impedance (R and C)
Input sensitivity, (1kHz, ref. rated power)
Signal/Noise ratio (A-weighted with cartridge connected)
THD (20Hz - 20kHz)
47kΩ / 100pF
3.2mV
76dB ref. 5mV
<0.04%
RIAA response accuracy (20Hz - 20kHz)
0.5dB
Line level inputs
Input impedance (R and C)
Input sensitivity (ref. rated power)
Maximum input signal
Signal/Noise ratio (A-weighted ref 1W)
Frequency response (20Hz - 20kHz)
Infrasonic filter
15kΩ / 100pF
160mV
>10V
88dB
0.5dB
-3db at 15Hz, 24dB/octave
0.01%
THD
Line level outputs
Output impedance
Pre-amp 600Ω
Tape Source Z + 1kΩ
Phones 220Ω
12V
Maximum output level
Tape 8V
Phones >10V into 600Ω
>500mV into 8Ω
Tone controls
Treble
Bass
7dB at 10kHz
10dB at 50Hz
+3dB at 70Hz
+6dB at 40Hz
Bass EQ
POWER AMP SECTION
Continuous output power into 8Ω *
40W (16dBW)
0.03%
Rated distortion (THD 20Hz - 20kHz)
Clipping power (maximum continuous power per channel)
IHF Dynamic headroom at 8Ω
50W
+6dB
IHF dynamic power (maximum short term power per channel)
8Ω 160W (22dBW)
4Ω 200W (23dBW)
2Ω 250W (24dBW)
>50
Damping factor (ref. 8Ω, 50Hz)
Input impedance
Input sensitivity (for rated power into 8Ω)
Frequency response
22kΩ / 880pF
1V
6Hz - 50kHz +0, -3dB
ref. 1W 100dB
Signal/noise ratio
ref. rated power 116dB
<0.03%
THD (20Hz - 20kHz)
© NAD Electronics. All rights reserved. E & OE
Download from Www.Somanuals.com. All Manuals Search And Download.
FM TUNER SECTION
Input sensitivity
Mono -30dB THD+N 10.3dBf (1.8µV/300Ω)
Mono 30dB S/N 14.2dBf (2.8µV/300Ω)
Stereo 50dB S/N 36dBf (34µV/300Ω) FM NR off
29dBf (16µV/300Ω) FM NR on
Stereo 60dB S/N 46dBf (110µV/300Ω) FM NR off
40dBf (56µV/300Ω) FM NR on
Capture ratio (45 - 65dBf)
AM rejection (45 - 65dBf)
Selectivity, alternate channel
Image rejection
<1.5dB
>60dB
65dB
70dB
I F rejection
Harmonic distortion
90dB
Mono 0.09%
Stereo 0.09%
Mono >80dB
Stereo >75dB
30Hz - 15kHz
50dB
Signal/Noise ratio
Frequency response 0.5dB
Channel separation at 1kHz
AM TUNER SECTION
Usable sensitivity
Selectivity
Image rejection
I F rejection
Signal/Noise ratio
Harmonic distortion
300µV
35dB
50dB
35dB
45dB
0.5%
Remote
NAD Link
No
No
PHYSICAL SPECIFICATIONS
Dimensions (W x H x D)
Net weight
420 x 108 x 380mm
7.5kg
9.0kg
Shipping weight
Power consumption (120 ~ 240V, 50/60Hz)
240VA
* 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.
© NAD Electronics. All rights reserved. E & OE
Download from Www.Somanuals.com. All Manuals Search And Download.
|