Audio Database


140,000yen(1975 release)

The Integrated Amplifier which aimed at the improvement in an audio property or an operationality by adopting a unique chassis structure.

In AU-9900, the preamplifier part and the tone control part have arranged a power part and power-source parts, such as a heat sinker and a power transistor, to the front panel side at the back side, and have adopted the divided layout.
This is the organization collected as an Integrated Amplifier of one set, after each functionality and operation have become independent, and the cross interferencee is reduced.

The right side panel of a frontside is equipped with input terminal groups, such as a player, the left-side side panel is equipped with the output-terminal group to the speaker, and the fluence of a signal system enables it to amplify to a smooth in the shortest path.
Moreover, the input terminal, the multiple contact switch, and the equalizer amplifier approached, shielding wire could be reduced, and the failure of the high region property by stray capacity is prevented.

The whole page hardwired-connection pure complimentary OCL scheme which has a differential-amplification circuitry in an input stage is used for a power amplifier part.
Moreover, the parallel push-pull circuit from which generous power is obtained by a low distortion is adopted as an output stage.

The input circuit of an equalizer part has 2 amplifier composition with the differential-amplification circuitry of dual transistor adoption of flat amplifier and an equalizer amplifier.
A RIAA correction is a CR+NF type which performs a high region and low-pass independently, respectively, and has obtained a more exact RIAA property and phase response.

In addition to the usual tone control, the triple tone control which can control a mid range is carried.
Moreover, a turnover frequency can be changed to low-pass [ three steps of ], and three steps of high regions with a tone selector.

The regulation is using the good and efficient toroidal transformer for a power-source part.
Moreover, a mass capacitor and a stabilized power source are combined and } power source stabilized to each block stage is supplied.

The temperature detection, the direct-current detection, and the ASO detection current limiter circuit are adopted as a protection network, and the speaker and the power transistor are protected to it.

A tone circuitry is passed and the tone-defeat switchpoint with which the flat frequency characteristic is acquired is carried.

A loudness-level-of-sound setups is possible to 0dB-10dB-20dB.

The tapes play circuitry of two circuitries, a tape-copy switchpoint, the tuner priority selector, a row / high filter, the muting switch, and an input impedance and a sensitivity changeover switch are carried.

Rating of a mode
Form Integrated Amplifier
Effective output (both channel operation) 80W+80W (4ohm, 8ohm, 20Hz - 20kHz)
80W+80W (4ohm, 8ohm, 1kHz, and less than THD 0.05%)
THD (Output power) 0.08% or less
Cross modulation distortion (70Hz:7kHz=4:1, SMPTE) 0.08% or less
Frequency characteristic (1 W:00) 10Hz-50kHz+0 -1 dB
Dumping factor 80 (8ohms)
RIAA deflection (30Hz - 15kHz) }0.3dB
Load impedance 4ohm, 8ohm
Channel separation (1kHz) Phono1, 2:55dB or more
Tuner, Aux1, 2, Tape Monitor: 60dB or more
A hum and a noise (IHF) Phono1, 2:65dB or more
Tuner, Aux1, 2, Tape Monitor: 80dB or more
Input sensitivity/impedance (1kHz) Phono1:2mV, 4mV, 8mV / 30kohm, 50kohm, 100kohm
Tuner, Aux1, 2, Tape Monitor1:130mV/50kohm
Tape Monitor2(Pin/Din):130mV
maximum permissible input (1kHz and less than THD 0.1%) Phono1:1000mV (8mV of Input-sensitivity switchings)
Aux, Tuner:3V
Output voltage Tape rec1(Pin):130mV
Tape rec2(Pin/Din):130mV/30mV
Tone control Bass:}10dB (30Hz)
Midrange:}5dB (1.5kHz)
Treble: }10dB (20kHz)
Tone selector Bass: 150Hz, 300Hz, 600Hz
Treble: 2kHz, 4kHz, 8kHz
A low filter - 3dB (20Hz), 12dB / oct
- 3dB (60Hz), 12dB / oct
A high filter - 3dB (7kHz), 6dB / oct
- 3dB (12kHz), 12dB / oct
Power dissipation 180W
Dimensions Width 460x height 160x depth of 375mm
Weight 17.9kg