Audio Database

Image of Integra A-810
Commentary

This is a W super type stereo pre-main amplifier.

The W / Super Servo system is used to solve the effects on sound quality due to noise components caused by DC leakage to the output and power source impedance in the power amplifier section.
The MC-compatible equalizer amplifier also incorporates a super servo system for ultra-low-frequency cut.

It uses a linear switching method that improves the linearity of circuit operation without changing bias at all and suppresses crossover distortion.
It is a class B operation in which two power transistors are used to divide and amplify the waveform, but by adopting a special correction circuit, crossover distortion that tends to occur at the junction of the waveform is suppressed.
Furthermore, High f is also applied to switching distortion.TThe 3-stage Darlington configuration of the power transistor and the double push-pull method have succeeded in removing it from the audible band.

MC-MM compatible, variable gain equalizers, and high-gain power amplifiers are the only two amplifiers used.
The equalizer amplifier is designed to improve S/N and high gain by developing a non-click capacitorless NF constant conversion method using a current conversion super servo method that does not require a head amplifier or step-up transformer when using an MC cart, and by using a 3-stage differential amplifier with excellent bare characteristics.
The power amplifier based on the W / Super Servo system achieves a wide dynamic range and low distortion factor by increasing its gain by 20 dB and omitting the tone amplifier.

In addition to the tone control, which simply varies the sound pressure in the low and high ranges, it is equipped with a softness circuit that can select three different tone characters.

A large twin-winded power transformer is used for the power supply section, and the Chemi-Con for rectification uses a multi-tab type low-impedance wide-range Chemi-Con as a low-inductance circuit directly connected to a printed circuit board in pursuit of the correlation between careful hearing and material properties.
In addition, hot copper bus lines are used for the power supply / distribution and ground lines of each section to ensure low impedance.

Uses a direct tone system that eliminates the sound quality degradation caused by tone amplifiers.

Uses an auto tracking bias system that detects the temperature difference of each part and enables always stable low distortion rate drive.

In order to suppress the generation of higher harmonics, a non-magnetic material is used to give priority to sound quality.

Model Rating
Type W super servo type pre-main amplifier
Rated Output (20 Hz ~ 20 kHz) 110W + 110W (8 Ω, AUX → SP out, both channels driven)
Total harmonic distortion rate (20 Hz to 20 kHz) 0.008% (AUX → SP out, rated)
0.006% (AUX → SP out, 1/2 rated)
0.003% (PH ・ MM → Rec out, 3 v)
0.01% (PH ・ MC → Rec out, 3 v)
Cross modulation distortion factor 0.005% (AUX → SP out)
Powerbandwidth 5 Hz to 100 kHz (IHF-3dB, THD0.2%)
Damping factor 100 (1 kHz, 8 Ω)
Frequency characteristic 20 Hz to 20 kHz ± 0.2 dB (PH → Rec out, RIAA deviation)
2 Hz ~ 100 kHz + 0 dB -1.5 dB (AUX → SP out, RIAA deviation)
Input Sensitivity / Impedance Phono MM : 2.5mV/47k Ω -100k Ω
Phono High MC : 2.5mV/100 Ω
Phono MC : 130 μ V/100 Ω -330 Ω
Tuner, AUX, Tape Play1, 2 : 150mV/47k Ω
Phono maximum allowable input
(1kHz/10kHz 0.05%)
Phono MM:300mV/1400mV
Phono High MC:300mV/1400mV
Phono MC:17mV/82mV
Output Voltage / Impedance Tape Rec1, 2 : 150mV/2.2k Ω
Pre Out : 1.5V/600 Ω
S/N ratio (IHF A, input short) Phono MM:86dB
Phono MC:69dB
Tuner, AUX, Tape Play1, 2 : 100 dB
Tone Control (Vol-16dB) Bass (70 Hz) : ± 8 dB
Treble (20 kHz) : ± 8 dB
Loudness + 6 dB + 4 dB, 100 Hz
Subsonic filter 15 Hz, 20 Hz 6dB/oct.
Muting -20dB
Pwer 100 V, 50/60Hz
Power consumption (Electrical Appliance and Material Control Law standard) 200W
AC outlet Unswitched-1 (200W)
Switched : 2 (total 200W)
External dimensions Width 435x Height 170x Depth 424 mm
Weight 20.3kg