Audio Database


79,800yen(around the 1975 time)

The Integrated Amplifier which inherited the basic performance of high-end model AU-7700 as it was, and was developed.

look up an input terminal by adopting the rear panel which has a unique structure -- it was alike, attached and is directly linked by an equalizer substrate and the shortest distance. The shielding wire which causes [ of a high region property ] aggravation by this is not used, but the SN ratio is improving.

Although the chassis was used as a common grounding of each circuitry with the conventional amplifier, this had affected the tone quality by the electric-current cross interferencee.
In AU-6600, a Tip-of-the-Day grounding is performed near an equalizer amplifier, and the quality of sound is improved.

In order that the first rank of a power amplifier part may have adopted the whole page hardwired-connection pure complimentary OCL circuitry with a differential-amplification circuitry and may maintain the 0VU potential of an outputting point, it has adopted the good differential-amplification amplifier and bias compensation circuit of a stability. Moreover, the drive stage consists of three-step Darlington connections with the transistor selected carefully.
Moreover, as a result of equipping the lower berth of the input terminal group of the rear panel with a large-sized heat sinker and taking out to the outside of amplifier, the heat-dissipation effect became good and the generous Oide power has been acquired.

The first rank input of an equalizer amplifier adopts a differential-amplification circuitry with the sufficient stability by } power source, has the stable direct-current balance, and has the outstanding special features, such as a high dynamic range, a high S/N ratio, and a low distortion.
Moreover, the property which was excellent in the NFB element selecting highly precise CRs carefully has been acquired.
Since the potential of the input/output circuitry is about 0v potential, it has prevented the unpleasant it1 noise generated at the time of a multiple-contact-switch switching.

A tone control is high-precision and has adopted NF type using the element of the good click stop type of a feel.
The stream composition of tone amplifier has 5 stone composition which used the differential-amplification circuitry by } power source for the first rank.
Moreover, according to liking etc., the more nearly optimal tone control property is acquired by considering it as the triple tone control which can adjust Bass and not only Treble but Midrange.

The tone multiple contact switch to which the roll off of Bass and each Treble and a turnover frequency are changed is carried.

The tone defeat is carried, a tone control circuit is bypassed, and the flat frequency characteristic is acquired.

The high filter and the low filter are carried.

The power-source blocking with margins, such as a heavy weight class transformer and silicon diode, was carried out to the power-source part, and it has to it.
Moreover, } power source by a stabilized power source is supplied to an equalizer amplifier and tone amplifier.

The protection network which combined the electronic circuitry and the relay is carried.
The speaker protection voltage detection circuitry and overcurrent detection circuitry in an outputting point are used, and self-s, such as an operation mistake, are also supported.
Moreover, the circuitry which prevents the pop noise generated at the time of power activation is also made to serve a double purpose.

The tapes monitor carries two circuitries and the monitor under a tape copy or sound recording can be performed.

carrying the speaker multiple contact switch A and B each can output independently. Or also simultaneously, it can output.

The pre-main separation switchpoint is carried and each can be used independently.

The standby AC plug socket and the large-sized grounding terminal are carried.

The loudness switchpoint, a muting switch, a Stereo/Mono switching mode switch, etc. are carried.

Headset jack loading.

DIN plug socket loading.


Rating of a mode
Form Integrated Amplifier
Effective output
Both channel operation 20Hz-20kHz:40W+40W (8ohm)
1kHz: 45W+45W (8ohm)
One-side-channel operation 1kHz:48W/48W (8ohm)
Music power 190W (4 ohm, 1kHz)
THD Pre Amp: 0.1% or less
Main Amp: 0.1% or less
Over All: 0.15% or less
Cross modulation distortion (70Hz:7kHz=4:1, SMPTE) Pre Amp: 0.1% or less
Main Amp: 0.1% or less
Over All: 0.15% or less
Power Band Width (IHF) 5Hz - 35kHz
Frequency characteristic (at the time of 1W output) 10Hz-40kHz+0.5 -1 dB
RIAA deflection (30Hz - 15kHz) }0.5dB
Dumping factor 30 (8ohm)
Input sensitivity/impedance Phono: 2.5mV / 50kohm
Tuner, AUX, Tape Monitor(Pin/Din):100mV /, 50kohm
Main Amp: 800mV / 50kohm
Phono maximum permissible input (less than THD 0.2%) 300mV
Output voltage (1kHz) Tape Rec(Pin/Din):100mV/30mV
Pre Amp:800mV
channel separation (1kHz) Phono: 50dB or more
Tuner/AUX, Tape Monitor: 55dB or more
Main Amp: 60dB or more
A hum and a noise (IHF) Phono: 70dB or more
Tuner, AUX: 85dB or more
Main Amp: 100dB or more
Tone control Bass: }13dB (50Hz)
Midrange: }5dB (1kHz)
Treble: }13dB (15kHz)
Tone selector Bass:300Hz/600Hz
Loudness (Volume-30dB o'clock) + 10dB (50Hz), +8dB (10kHz)
A low filter 70Hz=-3dB(6dB/oct)
A high filter 7kHz=-3dB(6dB/oct)
Muting -20dB
Power dissipation 90W
Dimensions Width 434x height 130x depth of 315mm
Weight 11.3kg