Model 931 is an
independent power amplifier that is so versatile that it can fit into any
system. It was designed so that all distortion is reduced to a minimum. Sone of
the factors that assure less distortion are quasi complementary SEPP, direct
coupled and differential circuitry. The power amplifier circuitry was analyesd
by a computer but this analysis was not restricetd to the audible range alone.
Onkyo found that the very low frequencies have a very important bearing on the
music even though inaudible. Since these low ffrequencies are not taken into
account when ordinary amplifiers are designed they cause very much
distortion. This distortion in the very
low frequencies causes IM distortion. This model is rated at 22 watts per
channel at 8 ohms. The T.H.D. of model 931 is rated at less than 0,05%. Whether
the amplifier is used at full or very low power this distortion rate does not
vary. Added stability is gained because a differential amplifier is used. In stability in an amplifier will put DC voltage on the loudspeaker
terminals and this will lead to distortion.
The differential amplifier also takes care of any distortion that could
come from fluctuations in the power supply voltage and temperature. The OCL
circuitry is an added factor why model 931 has less distortion, a
flatter response over the whole frequency range and especially good damping in
the lower frequency range.
Two Step Variable
Input Sensitivity
The input
sensitivity of model 931 is variable so that it can be matched perfectly to any
preamplifier. This makes it so very easy to use model 931 in any 4-channel
system.
Integrated Right and
Left Channel Attenuator
An integrated
attenuator for both channels is installed in model 931. This makes attenuation
of both channels very easy. With this added feature incorporated into its
design model 931 fits very easily into any 4-channel syetem.
Specifications
Dynamic Power: 70 W (IHF, 8 ohms); 100 W (IHF, 4 ohms)
RMS Continuous Power
(Single Channel Driven):
22 W + 22 W (8 ohms,
1kHz)
27 W + 27 W (4 ohms,
1kHz)
Total Harmonic
Distortion:
Rated output 1 kHz :
less than 0,1%
0,5 W output : less
than 0,05%
10 W output : less
than 0,05%
Inter Modulation
Distortion (SMPTE 70HZ : 7kHz = 4 : 1):
less than 0,05% at rated output
Frequency
Characteristic: 10 Hz - 80 kHz (+0 -1 dB
at normal output)
Power
Bandwidth: 10 Hz - 100 kHz (IHF -3 dB,
THD 0,5%)
Signal-to-Noise
Ratio: better than 100 dB (IHF A network
input shunt)
Damping Factor: 60 (DC - 30 kHz)
Load
Impedance: 4Ω - 16Ω
Gain: 22 dB ,
28 dB
Rated Input
Voltage: 1 V, 0,5 V
Input/Output
Characteristics: in -phase
Output
Terminal: Speaker-1
Power: AC 220 / 240 V, 50/60 Hz
Power
Consumption: 30 W (Electrical Goods
Control Standards)
AC Output: Unswitched 1
Dimensions (W x D x
H): 130 x 352 x 135 mm (5,2" x
14,1" x 5,4")
Weight: 3,5 kg (7,7 lb)