Twin powered AM/FM
and Stereo FM solid state receiver
Harman/Kardon
engineering skill has been incorporated into a superb receiver; the 930. we say
with full confidence that the Harman/Kardon 930 creates a new standard for
stereo high fidelity receivers
The twin-powered
amplifier section
The
Harman/Kardon 930 is the first
receiver in the world with two totally separate power supplies. Several
manufacturers imply that their receivers incorporate two power supplies in
reality, they employ a single supply with negative and positive voltages. The
930 also employs negative and positive voltages But, in addition, each chabnnel
is completely isolated and has its own power transformer and electrolytics. Each channel has its own regulated voltages
to permit that channel to respond to full RMS power output without being
affected by the other channel. Thus, the 930 guaranteed flawless performance
regardless of how much power the amplifier is called upon to deliver.
Power rating
Power rating is one
of the most abused specifications in high fidelity. Despite the existance of
standard procedures, it is often the manufacturer who determines the conditions
under which power is rated. Harman/Kardon engineers believe that Continuous power,
calculated from TMS voltage measurements, is the only meaningful way to rate
power output.
But such a rating is
still insufficient. Firstly, Continuous power output must be measured with both
channels driven simultaneously at a specified distortion level. Secondly, the
load impedance and power line voltage at which the measurement was taken must
be given.
Finally, the
measurements should be made across the entire frequency spectrum, rather than
at 1,000 Hz. In short, the conditions under which the receiver is measured
should be similar to those under which it will be used.
The preamplifier.
The 930's
preamplifier delivers a signal so pure that its distortion cannot be measured
with any degree of accuracy, even on the most sophisticated analysers. Only
professional separate components can match this preamplifier section's hum
noise and frequency response specifications.
One of the most
important specifications of any high quality preamplifier is that of phono
overload. The 930 specification is equal to or better than that of any receiver
available. The 930 preamplifier can handle an input signal 50 times greater
than that required to drive it to full output. This makes it virtually
impossible to distort the preamplifier output.
What is more,
absolute accuracy in playing back stereo records is assured as a result of the
extremely tight tolerance of the RIAA playback curve.
The Tuner section
The tuner section of
the 930 is a worthy companion to its superb amplifier. It employs high gain
integrated circuits and matched ceramic filters. The result is hard limiting
and excellent alternate channel selectivity. Hard limiting permits the
detection of all FM stations - weak or strong - with equal clarity. Noise and
distortion are completely eliminated. What's more, the excellent capture ratio
and alternate channel selectivity mean that even weak stations will emerge free
of interference from adjacent strong stations, impulse noise, and multipath
interference. Precise alignment of the IF section is "frozen" into
the circuitry and never requires realignment.
An FET front end,
coupled with a four ganged tuning capacitor assures maximum sensitivity. The
ultra-linear ratio detector delivers a precision composite signal to the
multiplex section. Thus, even the highest frequencies are free of distortion.
The multiplex
section employs balanced integrated circuitry which completely cancels SCA
interference and high frequency phase distortion. It maintains maximum stereo
separation throughout the entire audio range.
The FM muting
circuit is of unique design which provides a smooth-as-velvet muting
transition. In reality, it's simply go, no-go muting.
In short, the tuner
section of the 930 assures unsurpassed sensitivity and selectivity and achieves
a degree of excellence on a par with the receiver's amplifier.
Specifications
Amplifier Section
Power Output: 45/45 watts,
RMS , both channels driven into an 8 Ω
load, from 20 - 20,000 Hz at less than 0,5%
T.H.D. 120 volts, 50/60 Hz AC (same specification applies to 220 volts, 50 Hz
model)
Power Bandwidth: From less
than 10 Hz to beyond 40 kHz at less than 0,4% T.H.D. into 8 Ω , both channels driven simultaneously.
Total Harmonic Distortion :
less than 0,5% at 45/45 watts. Power output into 8 Ω , 20 - 20,000 Hz, both channels driven
simultaneously (typically runs 0,2% from 20 - 20,000)
00,7% (10 - 40,000
Hz) at 1 watt both channels driven simultaneously
Intermodulation
DIstortion : Less than 0,15% at full
rated output
Input
Sensitivity: 1,5 volts for full output
Hum and Noise: better than 85 dB below rated output
(Unweighted)
Damping Factor: 30:1 below 20 Hz
Input Impedance: 33,000 Ω
Frequency
Response: From below 4 Hz to beyond 70
kHz ±0,5 dB at normal power levels. From below 1 Hz to beyond 100 kHz ±1,0 dB
at normal power levels
Square Wave
Till: less than 5% at 20 Hz. Typical
tilt is less than 2%
Square Wave Rise
Time: less than 2 microseconds
Stability: Absolutely stable with all types of speakers
including electrostatic
Preamplifier Section
Audio Output: 0 to 2,5 V, RMS, minimum
Frequency
Response: from below 3 Hz to above 100
kHz ±0,5 dB
Total Harmonic
Distortion : less than 0,05% at 2 V
output, 20 - 20,000 Hz
Square Wave
Tilt: less than 5% at 20 Hz, Typical 2%
at 20 Hz
Square Wave Rise
Time: less than 1,5 microseconds
Noise
(Unweighted):
Low level: 65 dB below 2 volts at 10 millivolts input
reference.
High level: 80 dB below 2 volts, Volume control wide open
Residual : 90 dB below 2 volts
Input
Impedance:
Phono : 47 k Ω
Aux : 20 k Ω
Output Impedance: less than
1,000 Ω
Phono Overload: 90 millivolts
Tone Controls: ±12 dB boost and cut, bass and treble
Tuner Section
FM sensitivity: 1,8 mV , IHF
Limiter
Saturation: less than 1,5 mV
Ultimate
Signal-tonoise: 70 dB
Capture Ratio: less than 2 dB
Alternate Channel
Selectivity: better than 50 dB
Image
Rejection: 90 dB
Spurious Response
Rejection: 90 dB
IF Rejection: 90 dB
Fundamental Plus
Half IF: 90 dB
AM rejection: better than 60 dB
Level Meter
Sensitivity: 50 mV (25%); 1000 mV (100%)
Audio Frequency
Response : Below 15 Hz to beyond 30 kHz
±1,0 dB
Total Harmonic
Distortion :
Mono : 0,5%
Stereo : 0,6%
Multiplex
Separation:
100 Hz : 33 dB
1 kHz : 38 dB (40 dB typical)
10 kHz : 30
dB
Antenna Impedance: 75 and 300
Ω
AM Loop
Sensitivity: better than 200 mV /1m
Selectivity: 35 dB average of lower and upper
selectivities
Image
Rejection: better than 60 dB
IF Rejection: better than 60 dB
Dimensions (W x H x
D): 432 x 349 x 120 mm (17" x
13-3/4" x 4-3/4")
Weight: 13,1 kg (29 lbs)