Audio Database

The

Marantz PM-80BL 60,000yen(around the 1989 time)

Description
 
The Integrated Amplifier which adopted the Class-A / AB class change scheme.

In addition to a large-sized power transformer, the special edition electrolytic capacitor of 18,000 micro Fx2 is adopted as a power-source part, and the electric current stabilized also in the time of the Oide power is supplied.
Moreover, the OFC line of a very thick is adopted as a speaker circuitry, and the powering to the power transistor is performed smoothly.

The powerful noise-killer circuitry is carried.
The rectification noise produced when changing an alternating current into a direct current. Since this RF noise near 1MHz has an ill effect on a tone quality also in a slight quantity from 100kHz, this RF has been cut by the noise-killer circuitry.
Furthermore, the noise is thoroughly eliminated by the circuitry of separating a rectifier circuit from a signal system.

The power transistor has adopted the parallel push pull stream composition by the power transistor of Pc-100W excellent in the linearity, and is raising the gain as a three-step Darlington connection.
Moreover, the heat sink is suppressing the cross interferencee in the output circuit as a right-and-left independent structure, and, thereby, the crosstalk is decreasing.

Low-noise FET is adopted as a phone equalizer, combination with IC for audios constitutes low-noise amplifier, and the purity of the phone signal with low level is protected.
Moreover, the modulation by low frequency is prevented by carrying out the roll off of the 30Hz or less.

The material selected carefully is used for a part.
The electrolytic capacitor which uses for a separator the paper with which the fiber type protein fibroin and Manila hemp of silk were mixed is adopted especially as a signal system.
Moreover, the paper polyesters base material excellent in vibration suppression nature is used for the printed circuit board, muddiness was suppressed and the highly transparent tone quality is realized.

A Class-A / AB class circuit changing switch is prepared, and it has the stream composition which can enjoy the tone quality of a Class-A.
Usually, it is a Class-A, and when large power is required, change operation of being AB class is possible.
The circuitry which arranged the voltage change circuitry near the power stage, and a bias change are suppressing the influence on a tone quality, such as attaining shortest-ization of the distance by a photo-coupler, to the minimum.

With a Source-Direct switchpoint, all of switchpoints and control circuits, such as a tapes monitor and a processor, are jumped, and the direct input to power amplifier is possible through an exclusive volume.

Five input terminals are carried and the tapes input/output terminal carries three lines.
Furthermore, it is also possible to also carry the processor termination and to connect a graphic equalizer etc.

Rear
Power Electrolytic Noise-killer

Rating of a mode
Form Stereo Integrated Amplifier
Output power (20Hz - 20kHz, both channel simultaneous drive)
Class AB : 140W+140W (4ohms)
120W+120W (6ohms)
100W+100W (8ohms)
Class A : 20W+20W (8ohms)
Dynamic power
Class AB : 340W+340W (2ohms)
220W+220W (4ohms)
170W+170W (6ohms)
THD (1kHz, 8-ohm load intensity) 0.0008%
Cross modulation distortion (SMPTE) 0.008%
Output bandwidth (an 8-ohm load intensity, 0.03%) 10Hz - 50kHz
Frequency characteristic compact disk and a Source Direct: 10Hz-100kHz+0 -3 dB
Dumping factor 180 (an 8-ohm load intensity, 20Hz - 10kHz)
Input sensitivity/impedance Phono MC: 250 microvolts/100 ohms
Phono man month: 2.5mV/47kohm
High SFT Level: 150mV/33kohm
Phono maximum permissible input (1kHz) MC:16mV
MM:160mV
RIAA deflection (20Hz - 20kHz) ±0.2dB
SN ratio (A network) Phono MC:75dB
Phono MM:85dB
High Level:105dB
Tone control Bass: 100Hz, ±6dB
Treble: 10kHz, ±6dB
Power source AC100V, 50/60Hz
Power consumption 220W (Electrical Appliance and Material Control Law)
Dimensions Width 454x height 165x depth of 380mm
Weight 17.5kg