Kensonic Accuphase P-300
¥ 195,000 (released in August 1973)
The first power amplifier released by Accuphase in the era of Kensonic.
It was developed with the aim of an amplifier that can accurately follow subtle changes in music and strong amplitudes.
All stages from input to output are directly connected push-pull configuration.
Therefore, the bare characteristics before applying NFB (negative feedback) are improved.
Six high-output power transistors are used for each channel at the output stage, and these are called triple push-pull.
Pure complimentary service direct connection system is adopted for the circuit system.
The power supply uses a 40,000 μ Fx2 large-capacity filter and condenser.
The parts are tested from the viewpoint of the change of sound quality and durability, and are selected carefully.
We have adopted a protective circuit that uses a relay to shut down when a cord short-circuits after the output terminal, a problem occurs in the speaker, or a problem occurs inside the P-300.
When an error occurs, the lamp of the power meter blinks to indicate the error.
It has a built-in band-pass filter that removes at 18dB/oct. frequencies below 17 Hz and above 24 kHz in order to cut noise components such as unwanted input caused by the rumble of a phono motor or arm resonance in the ultra-low frequency range, and unwanted input in the ultra-high frequency range.
It uses a large power meter and can display by switching between 0 db, -10dB, and -20dB range.
8 Ω load, 150W is scaled as 0 dB.
Equipped with a speaker selector switch that can switch between four sets of stereo speakers, and with two selectable inputs.
One circuit of the output terminal and one circuit of the input terminal are installed inside the front sub panel.
|Type||Stereo power amplifier|
(Both channel drive, 20 Hz to 20 kHz, distortion rate 0.1%)
|4 Ω load : 200W/ch
8 Ω load : 150W/ch
16 Ω load : 75W/ch
|Harmonic distortion factor (20 Hz to 20 kHz)||Rated output : 0.1% or less
0.05% or less at -3dB output
0.1% or less at 50 mW output
|IM distortion factor||0.1% or Less (at Rated Output)|
|Frequency response (8 Ω load)||20 Hz ~ 20000 Hz + 0 -0.2 dB|
|Damping factor||20 or More (8 Ω Load, between 20 Hz to 20 kHz)|
|Rated input / input impedance||1.0V/100k Ω|
|S/N ratio (at rated output)||100 dB or more|
|Stereo headphone||Low output impedance type|
|Audio bandpass filter||17 Hz or Less, 24 kHz or More, 18dB/oct.|
|Power limiter||Full Power, 1/2, 1/4, Switch Over|
|Semiconductor used||Transistor : 73
Diode : 88 units
Thermistor : 2 pcs
IC : 1
|Pwer||100, 117, 220, 240V/50 ~ 60 Hz|
|Power consumption||No input : 100W
8 Ω load rated output : 510W
|External dimensions||Width 445x Height 152x Depth 355 mm|