Panasonic SU-V900

Commentary

This is a pre-main amplifier with twin monaural configuration that was developed by investing know-how of digital direct drive.

In the SU-V900, the sound quality design know-how of the digital direct drive is applied to the power amplifier section. The power amplifier section, which was conventionally composed of one unit, is composed of two units, a class AA power amplifier with a voltage amplification degree of 1 (0 dB) and a flat amplifier with a voltage amplification degree of 30 dB.
Since the 0 db power amplifier does not perform voltage amplification, it has excellent transmission characteristics such as low noise level. The 0 db amplifier operates stably by combining a unique classAA circuit and a floating power supply that share voltage control and current control with separate amplifiers.
By mounting a 30 dB flat amplifier in the shield case of the preamplifier section, a large current at the output stage of the power amplifier section is prevented from adversely affecting the input stage of the power amplifier section.
These configurations provide both ultra-low distortion and excellent speaker drive capability.

The power supply section is equipped with a 170 VA large-capacity transformer independently on the left and right sides. This transformer uses oxygen-free copper wires and is sealed with plastic in the shield case to reduce mechanical vibration and magnetic radiation.
The electrolytic capacitor is equipped with a newly developed X-Pro twin capacitor. In this capacitor, two electrolytic capacitors for power supply (+ side and - side) are enclosed in a resin case with a copper cap, and vibration absorbing material is used to reduce mechanical vibration and electromagnetic radiation.

The power amplifier section has a twin monaural configuration in which the left and right sides are separated and arranged separately. Moreover, the preamplifier section has a T-shaped configuration with a tight shield to reduce interference between the left and right channels caused by electromagnetic waves from the large current of the power amplifier section.
In addition, the left and right power amplifiers are separately mounted on a 2-mm-thick folding chassis with narrow plates, and the front plate and rear plate are fixed at two center angles, making the chassis structure less susceptible to vibration.

The input section is equipped with a tight shield plate to deal with electrical and magnetic noise.

Parts such as high-purity OCC wire and PXS electrolytic capacitor are used in each part.

Equipped with power amplifier direct function, high purity signal transmission is realized by simple connection of signal line.

Model Rating

Type	Integrated amplifier
Power Amplifier Unit
Effective power	100W + 100W (20 Hz ~ 20 kHz, T. H. D 0.007%, 6 Ω)
Total harmonic distortion factor	0.003% (20 Hz to 20 kHz, -3dB, 8 Ω)
Damping factor	110 (8 Ω) 55 (4 Ω)
Preamplifier Section
Frequency characteristic	Phono : RIAA standard curve ± 0.2 dB Tuner, CD, Tape1, 2, DAT, adapter : 0.8 Hz to 120 kHz + 0 dB -3dB
Input Sensitivity / Impedance	Phono MM : 2.5mV/47k Ω MC : 170 μ V/220 Ω Tuner, CD, Tape1, 2, DAT : 150mV/47k Ω Power amp direct : 1V/22k Ω
Signal-to-noise ratio	Phono MM:88dB(IHF'66) MC : 72 dB (250 μ V input, IHF' 66) Tuner, CD, Tape1, 2, DAT : 104 dB (IHF' 66) Power amp direct:115dB(IHF'66)
Maximum allowable input	Phono MM:160mV MC:10mV
Tone control	Bass : + / - 10 dB (50 Hz) Treble : ± 10 dB (20 kHz)
<General>
Pwer	100 VAC, 50Hz/60Hz
Power consumption	235W
External dimensions	Width 430x Height 186x Depth 438 mm
Weight	21kg