Audio Database


Pre-main amplifier with dual super non-feedback circuit.

The PMA 960 is equipped with a dual super non-feedback circuit that enhances the non-feedback system.
This circuit consists of a distortion servo circuit in which the N-channel and P-channel transistors of the power stage mutually cancel out the distortion.
The dual super no-feedback circuit has no NFB loop that returns the signal to the input side, so the transmission speed of the signal approaches that of the bare circuit, and there is no dynamic distortion that greatly affects the auditory quality. It also has the advantage of theoretically making the static distortion 0 and increasing the slew rate.
In addition, the dual super no-feedback circuit with a high removal effect has an excellent distortion removal effect up to the high-order harmonic distortion region of 20 kHz or more. In addition, since there is no NFB loop, the influence of the back electromotive force, etc. does not reach the voltage amplification stage (pre-driver stage, etc.) when the speaker is connected, and dynamic distortion does not occur. There are various other advantages.

The flat amplifier, which is heavy for CD playback, has been thoroughly upgraded to high speed to improve the slew rate.
In addition, it is fully capacitorless (fully DC configuration) for all signal paths and non-switching class A power amplification.

A power transistor of Pc130W is connected in parallel to the output stage.
The power supply is equipped with a large 390 VA toroidal transformer, four newly developed φ 50x100mm block capacitors (12,000 μ Fx4) for audio equipment with separate left and right channels near the output stage to avoid mutual interference, and a fast recovery diode for high-speed rectification. As well as realizing high power, dynamic power characteristics with allowance are obtained.

The equalizer amplifier uses a wide-band equalizer with a low-noise FET differential amplifier connected in parallel at the first stage. This equalizer amplifier is designed to suppress the increase of high-frequency distortion caused by high-impedance (MM type) cartridges.
In addition, the allowable input has been improved by a newly designed circuit that increases the supply voltage by approximately 20% compared with the conventional circuit by adopting a newly developed high-voltage IC.

It has a DAD dedicated input terminal to connect a CD player, etc.

Equipped with broadband real-time tone control with turnover switching.

Equipped with high-speed protection circuit.

The power cord uses 37 φ 0.26 mm x cords with polarity indication.

There are 2 variations, black and champagne gold.

Model Rating
Type Pre-main amplifier
<Power Amplifier Unit (Tuner → SP out)>
Rated Output (Both Channels Driven, Sine Wave Continuous Output) 170W + 170W (6 Ω)
140W + 140W (8 Ω)
Input Sensitivity / Impedance 150mV/47k Ω
Total harmonic distortion factor 0.003%
Cross modulation distortion factor Not more than 0.002%
TIM distortion factor Measurement limit value or less
Slew rate ± 350 V / μ sec or more
Output bandwidth (both channel drive) 5 Hz ~ 80 kHz (THD 0.02%)
Frequency response (at 1W output) 1 Hz ~ 250 kHz + 0 -3dB
Output Impedance (1 kHz) 0.1 Ω
Output terminal Speaker AORb : 6 Ω ~ 16 Ω
Speaker A + B : 12 Ω ~ 16 Ω
Headphone Jack : 550mW/8 Ω
Preamplifier Section
Input Sensitivity / Impedance Phono MM : 2.5mV/47k Ω
Phono MC high : 0.25mV/100 Ω
Phono MC low : 0.125mV/100 Ω
DAD, Tuner, Aux, Tape : 150mV/47k Ω
Maximum Output / Rated Output 14.5V/150mV
Total harmonic distortion factor 0.001% or Less (1 kHz, 8 V)
RIAA deviation 20 Hz to 100 kHz ± 0.2 dB (MC/MM)
SN ratio (input ratio (input short circuit, weight A) Phono MM : 90 dB at 2.5 mV input
Phono MC : 75 dB at 0.25 mV input
DAC, Tuner, Aux, Tape : 110 dB at 150 mV input
Tone control Bass : ± 8 dB (50 Hz, 100 Hz)
Treble : ± 8 dB (10 kHz, 20 kHz)
Subsonic filter 18 Hz, 6dB/oct.
Muting -20dB
Loudness control characteristic Low frequency : + 7 dB (100 Hz)
High frequency : + 6 dB (10 kHz)
Pwer 100 VAC, 50Hz/60Hz
Power consumption 245W
External Dimensions (including legs, knobs, terminals) Width 470x Height 168x Depth 440 mm
Weight 15kg