Audio Database


Marantz PM-6a 160,000yen(around the 1981 time)

The Integrated Amplifier which carries a QuarterA system.

When fixed power (PM-6a 30W) fixes a bias current, QuaterA considers it as a perfect pure Class-A operation and the power is exceeded (it is 30W to 120W in PM-6a), it is a scheme which switches to AB class operation automatically.
The Marantz uses for the change the fast-switching circuitry developed newly, and it is carrying out to the pure electronic target.
The power amplifier part which carries this QuaterA system has whole page perfect push pull DC composition with a built-in DC servo circuitry, and has acquired the outstanding property by the Low-TIM design which reduced a transitional distortion by an improvement and low NFB-ization of the nakedness property of amplifier.

The full-scale headphone amplifier which supplied 13 transistors per channel of one side to only for MC cartridge from the input stage of 4 parallel push pull with a super-low-noise transistor to the output team of a SEPP stream composition is carried.

The phone amplifier part has realized high SN and a quantity dynamic range by a whole page perfect push-pull-circuit stream composition original with a Marantz. Furthermore, the polypropylene capacitor of class was adopted as the equalizer element 2% with the metal film resistor of 1% of error class, and the outstanding property has been acquired.

The TONE switchpoint which can bypass the whole tone amplifier circuitry is carried.
A flat amplifier output is direct connected with a Tone Out position to power amplifier, and he can enjoy himself by a purer quality by it.

The low profile and mass power transformer which improved thermal resistance by special resin filling, and super audio capacitor 22,000micro-Fx2 which were selected carefully from the tone quality are carried in the power-source part.
Moreover, the high heat-pipe scheme of the heat-dissipation effect is adopted, and the operation stabilized also at the time of the pure Class-A which consumes a large current has been obtained.

Two phone inputs are carried and man-month load selector of "27kohm, 47kohm, 100kohm" other than MC head amplifier position is carried in "Phono1" in it.
Functionalities, such as a tape-copy switchpoint in which mutual dubbing of the two more decks is possible, a loudness of a two-step, a right-and-left independent tone control, are carried.

There was a mahogany cabinet as an option.

Rating of a mode
Form Stereo Integrated Amplifier
Output power (20Hz - 20kHz) 120W+120W (8ohms)
THD (20Hz - 20kHz) 0.015% or less (at the time of an Output power)
Cross modulation distortion (60Hz:7kHz=4:1) 0.015% or less (at the time of an Output power)
Frequency characteristic 5Hz-100kHz+0 -2 dB
RIAA deflection 20Hz-20kHz±0.2dB
SN ratio (IHF-A) Phono MM:86dB
Phono MC:68dB
Tape, Tuner, AUX: 110dB
Power dissipation 350W
Dimensions Width 416x height 146x depth of 332mm
Weight 16.0kg
Option Wood cabinet WC-77N (12,500yen)