Audio Database


Pioneer A-120D
82,000yen(around the 1985 time)

The Integrated Amplifier developed as a try angle drive system aiming at the play of rich musicality employing efficiently the property which was excellent in the digital source.

The figure of the ideal of amplifier is pursued and the review is aimed at from the power-source part.
First, a large-sized power transformer is carried in Lch and the object for Rch of a power amplifier part, respectively, and power is supplied to each output stage and the voltage amplification stage.
Furthermore, a 16,400-micro F large capacity power supply capacitor is adopted per single-sided channel. Moreover, 2 parallel connection of the power transistor per single-sided channel is carried out, and the thorough power part is strengthened, such as considering it as a parallel push pull.
Moreover, not only a power transformer but the construction itself adopts a monophonic stream composition, and a power amplifier part puts its heart and soul into the monophonic stream composition until it begins a power transformer, and a rectifier circuit and a power source capacitor and results in each part article, a product line, and the layout of a radiator. Thereby, the cross interferencee was suppressed and the high separation is attained.

The line straight circuitry which jumps a tone control is adopted.

The non switching circuit TypeII which improved the non switching circuit further is carried.
The instant stabilization of the idle current was carried out, and thermal distortion is proposed sharply.
Moreover, the nonlinear distortion of an output stage is also improving to 1/30 by detecting and rectifying the difference of an input signal and an output signal.

MC head amplifier is carried.

What was selected carefully to each parts was used, the capacitor and the resistor were begun, and the oxygen-free-high-conductivity-copper line is adopted as main product-line material and a very-thick power cord.
Moreover, it has pierced through the thought of a tone-quality first priority, such as dividing a grounding point into a power supply system and a signal system.
Furthermore, the large-sized vice type which can perform a stable current supply source is adopted as a speaker terminal, and the tinning treatment nonmagnetic also in each pin jack is carried out.

It has five input terminals and two tapes terminations.
Especially compact-disk position serves as a design in which the high purity source, such as also considering a circuitry top as the shortest product line as a main source, is employed efficiently.

The sub- wood of the photograph was an option.


Rating of a mode
Form Non switching Integrated Amplifier
Effective output
20Hz - 20kHz : 120W+120W (6 ohm, both channel drive)
100W+100W (8 ohm, both channel drive)
1kHz: 160W+160W (4 ohm, both channel drive)
130W+130W (6 ohm, both channel drive)
110W+110W (8 ohm, both channel drive)
THD (20Hz - 20kHz) 0.003% (at the time of an effective output)
Cross modulation distortion (50Hz:7kHz=4:1) 0.003% (20Hz - 20kHz, 100W, 8ohm)
Output bandwidth 5Hz - 55kHz (IHF, both channel drive, THD0.01%)
Output-terminal Speaker(4ohm-16ohm): A, B, A+B
Tape Rec1, 2:150mV
Dumping factor 100 (20Hz - 20kHz, 8ohm)
Input sensitivity/impedance Phono man month: 2.5mV / 50kohm
Phono MC: 0.2mV/100 ohms
compact disk, Tuner, AUX, Tape Play1, 2:150mV / 30kohm
Phono maximum permissible input (1kHz, THD0.003%) MM:200mV
Frequency characteristic Phono man month: 20Hz-20kHz}0.2dB
compact disk, Tuner, AUX, and Tape Play:2Hz-100kHz+0 -3 dB
SN ratio
(IHF, A network, a short circuit)
Phono MM:88dB
Phono MC:70dB
compact disk, Tuner, AUX, Tape Play: 110dB
Stereo separation 88dB(10kHz)
Tone control Bass: }8dB (100Hz)
Treble: }8dB (10kHz)
Filter Low: 15Hz, 6 dB/oct.
Supply voltage AC100V, 50Hz/60Hz
Power consumption (Electrical Appliance and Material Control Law) 300W
Dimensions Width 420x height 151x depth of 427mm
Weight 14.2kg
Option Sub- wood JA-A120 (4,000yen)