Technics SE-A7000

Commentary

Stereo power amplifier using newly developed MOS class AA circuit

MOS class AA circuit is mounted.
The class AA circuit realizes high power and complete class A voltage control by amplifying the voltage of the music signal input from the source and supplying the current to drive the speakers with separate amplifiers. The MOS class AA circuit is based on this class AA amplifier. The voltage control amplifier uses a new element, MOS FET, which is an amplifier with extremely high input impedance and excellent high-frequency characteristics, to further enhance the linearity of signal control.
The bipolar transistor improves the speaker drive power by supplying a strong current, and realizes a stable high output.

Ten large-capacity electrolytic aluminum capacitors of the newly developed MASTER series with a total capacity of 75,000 μ F are installed.
Mechanical properties of this condenser have been improved by using newly developed special damping aluminum for the case.

Three power transformers are installed, one for each current supply amplifier for left and right channels, and one for voltage control amplifier for both channels.
These transformers are made of oxygen-free copper wires and are highly regulated by high-density, high-efficiency technology. Furthermore, they are enclosed in a 3-layer magnetic shield case with special resin to suppress mechanical vibration and leakage flux and greatly reduce electrical noise.

3 mm thick weight class top plate, high rigidity chassis, large insulator, side wood with real wood mirror finish, etc. are adopted, and magnetic radiation and mechanical vibration are greatly reduced.

Equipped with balanced input terminal.
This terminal achieves stable transmission by using a balanced transformer method with a DL-type permalloy core and a tight shield to prevent the influence of external magnetism.

It is equipped with a high precision large power meter with 10 mm thick bronze glass.
This meter can read directly from 0.0001W to 300W.

OFC bus c bus bars and LC-OFC internal wiring.

Electronic speaker selector is used. Highly reliable gold-clad contact is used for terminal switching.
In addition, large gold plated terminals mounted on an aluminum base are used for speaker terminals.

The internal construction makes the left and right channels independent independent left and right channels to reduce noise and crosstalk between the two channels.

Newly developed non-inductive resistor is adopted.
By increasing the alumina content -frequency response by preventing signal reproduction from being hindered by Joule heat generated by itself by increasing the alumina content of the base insulator.

Uses a PC-OCC power cord with polarity indication.

Model Rating

Type	Stereo power amplifier
Rated output	240W + 240W (4 ω, 20 Hz-20 kHz, 0.005%) 200W + 200W (6 ω, 20 Hz-20 kHz, 0.005%) 170W + 170W (8 ω, 20 Hz-20 kHz, 0.005%)
Frequency characteristic	20 Hz ~ 20 kHz + 0 -0.1 dB 0.8 Hz ~ 150 kHz + 0 -3dB
Signal-to-noise ratio	93dB(EIAJ) 120dB(IHF'66)
Input Sensitivity / Impedance	Normal/DC : 1.2V/47k Ω Balance : 1.2V/600 Ω
Meter indication range	0.0001W ~ 300W (8 Ω)
Pwer	100 VAC, 50Hz/60Hz
Power consumption	420W
External dimensions	Width 483x Height 208x Depth 473 mm
Weight	38kg