Audio Database


Kensonic Accuphase P-300
195,000 yen(August, 1973 release)


Power amplifier of No. 1 which the Accuphase announced to the Kensonic age.
It was developed aiming at the amplifier which can be surely followed also to a musical delicate change and mighty amplitude.

It has composition of a whole page direct connection push pull from the input to the output.
For this reason, the nakedness characteristic before applying NFB (negative return) is improved.

It uses the Oide power power transistor each six channels at a time for an output stage, and this is made into the triple push pull.
The direct connection system of pure complimentary is used for a circuit system.

The mass filter capacitor of 40,000 micro Fx2 is adopted as a power-source part.

The part is tested, selected carefully and adopted from change of sound quality, and a durable field.

If a cord short-circuits henceforth [ output terminal ], abnormalities occur to a speaker or abnormalities arise by P-300 core, the protection circuit intercepted by relay will be adopted.
At the time of an abrupt increase, the lamp of a power meter blinks and abnormalities are told.

In order to cut noise ingredients which happen by the run bull of a phone motor, or super-low-pass arm resonance, such as an unnecessary input and an unnecessary input of super-upper register, the band pass filter which removes 17Hz or less 24kHz or more by 18 dB/oct is built in.

The large-sized power meter is adopted, and it can change and display in a 0dB -10dB-20dB range.
8-ohm load and 150W are set up as 0dB.

The speaker selector switch which has a four-set stereo speaker switched is carried. Moreover, a two-line change of an input is possible.
One circuit of an output terminal and one circuit of an input terminal are established in the core of a front sub panel.


Rating of a mode
Form Stereo power amplifier
Output power
(Both channel drive, 20Hz - 20kHz, 0.1% of distortion)
4ohm load: 200 W/ch
8ohm load: 150 W/ch
16ohm load: 75 W/ch
THD (20Hz - 20kHz) At the time of an Output power: 0.1% or less
- At the time of a 3dB output : 0.05% or less
At the time of a 50mW output: 0.1% or less
IM distortion 0.1% or less (at the time of an Output power)
Frequency response (8-ohm load) 20Hz-20000Hz+0 -0.2 dB
Dumping factor 20 (for 8-ohm load and 20Hz - 20kHz) or more
A rated input / input impedance 1.0V/100kohm
S/N ratio (at the time of an Output power) 100dB or more
Stereo headphone Low Output-load-impedance type
Audio band pass filter 17Hz or less, 24kHz or more, 18 dB/oct
Power limiter Full power, 1/2, 1/4, a switch change
The semiconductor used Transistor: 73 pieces
Diode: 88 pieces
Thermo sensitive register: Two pieces
IC: One piece
Power source 100, 117, 220, 240V / 50-60Hz
Power consumption At the time of no inputting: 100W
At the time of an 8ohm load Output power: 510W
Dimensions Width 445x height 152x depth of 355mm
Weight 25kg