Accuphase P-300S

Commentary

This is a stereo power amplifier in which all amplification stages are composed of symmetric push-pull, and in addition, physical characteristics of measurement limit are realized by adopting DC unit amplifier, adoption of carefully selected parts, and listening test.

Based on active elements with excellent high-frequency characteristics, all amplification stages are composed of symmetric push-pull.
As a result, excellent start-up characteristics, linearity and stability can be achieved with a small amount of NFB, and TIMs are prevented and low distortion is achieved.

The capacitor in the NFB loop is removed in order to realize sound quality with less coloration, and a DC amplifier configuration is adopted.
In addition, the power supply is further stabilized to suppress DC drift, the center voltage is stabilized by using dual transistors for the input, and the temperature variation of the active elements is made uniform to achieve long-term stable operation.

The power supply section is equipped with a heavy-duty large power transformer and a 40,000 μ Fx2 large-capacity filter condenser.
The parts used in the circuit are carefully selected based on consideration of changes in sound quality and durability tests.

It is equipped with a speaker protection circuit. When a short circuit occurs in the speaker cord or an error occurs in the amplifier / speaker, the speaker protection circuit catches the error and the relay cuts off between the P-300S and the speaker.
This circuit is also used to prevent the shock noise that occurs when the power supply of the amplifier is turned on / off.

It is equipped with a subsonic filter that cuts frequencies below 17 Hz at 18dB/oct. in order to cut low-frequency noise caused by record warping and eccentricity.

Equipped with a left / right independent attenuator that can be adjusted up to -20dB in 1 dB steps.

It is equipped with a large power meter of output direct reading type, and can read 0 dB output and wattage at 8 Ω load.
In addition, a -10dB and -20dB range switch is provided so that it can be used even at low volume.

For high-efficiency speakers or multi-amp systems, if you want to limit the power more than necessary, a power limiter switch is included. You can choose between full power, 1/2 or 1/4.

There was a wood case with natural wood walnut finish sold separately.

Model Rating

Type	Stereo power amplifier
Rated output (both channel drive 20 Hz to 20 kHz, Distortion 0.03% or less)	200W/ch (4 Ω) 150W/ch (8 Ω) 75W/ch (16 Ω)
Harmonic distortion factor (20 Hz to 20 kHz)	0.03% or Less (Rated Output) 0.01% or Less (at -3dB Output) 0.05% or Less (at 50 mW Output)
IM distortion factor	0.01% or Less (at Rated Output)
Frequency characteristic	20 Hz ~ 20 kHz + 0 -0.2 dB at Rated Output 1 Hz ~ 250 kHz + 0 -3dB at 1W Output
Damping factor	60 (8 Ω load, 40 Hz)
Rated input / input impedance	1.4V/50k Ω
S/N ratio (input short, IFF-A curve)	115 dB or more (at rated output)
Stereo headphone	Low output impedance type
Subsonic filter	17 Hz, 18dB/oct.
Power limiter	Full Power, 1/2, 1/4, Switch Over
Semiconductor used	Transistor : 97 FET : 2 IC : 1 Diode : 92 pcs
Power supply voltage	AC100V/117V/220V/240V, 50Hz/60Hz
Power consumption	No input : 100W 8 Ω load rated output : 510W
External dimensions	Width 445x Height 160 (Including Legs) x Depth 355 mm
Weight	25kg
Sold Separately	Wood Case A-2 (¥ 15,000)