ONKYO Integra A-2001

Commentary

A pre-main amplifier that combines a high-purity amplifier circuit with a simple transmission circuit, and also incorporates a D/A converter.

The power amplifier section uses a newly developed optical drive system.
In this method, the reference current of the first stage differential amplifier circuit is obtained from a photovoltaic element that generates a constant voltage when light is irradiated. By obtaining a reference current with higher accuracy than that of the conventional method, highly accurate V to I conversion is performed.

In the final stage of the power block, a parallel push-pull system composed of four large output transistors with a collector loss of 150W is adopted to realize an output with a margin.

To prevent interference between analog and digital circuits in the power supply section, a dedicated power transformer is used for digital circuits, and a super-large power transformer with windings for each secondary side Line 5 is installed for analog circuits.
The rectifier and smoothing circuit employs eight low-impedance twin-roll Chemi-Cons (96,000 μ F) with a resistance value one third of that of conventional ones, and a high-speed rectifier diode with a fast recovery time to provide a stable current supply.

In order to prevent adverse effects of vibration, we have adopted a high carbon steel rigid chassis with high density, high mass and excellent vibration resolution capability. All components such as power transformers and amplifier circuit boards are mounted on this base.
This chassis has a 6-point mounting structure that ensures a stable setting by balancing the weight of the Integra A-2001.

In order to prevent distortion due to mutual interference of each circuit, four block complete separate construction is adopted.
The power supply block is placed at the end of the box and completely separated by a shield plate. Furthermore, the light-driven D/A converter and the digital processing circuit are each enclosed in an electromagnetically shielded copper-plated case and separated on the opposite side from the power supply.

The digital circuit is equipped with a newly developed real 18-bit optically driven twin D/A converter.

Model Rating

Type	Digital basic amplifier
Amplifier Unit
Rated output (20 Hz to 20 kHz CD → sp out, both channels driven)	170W + 170W (6 Ω) 150W + 150W (8 Ω)
Dynamic Power	490W + 490W (2 Ω) 350W + 350W (4 Ω) 220W + 220W (6 Ω)
Total harmonic distortion rate (20 Hz to 20 kHz)	CD → sp out : 0.004% (8 Ω at rated output) Phono MM → rec out : 0.003% (at 3 v output) Phono MC → rec out : 0.015% (at 3 v output)
Intermodulation distortion factor (20 Hz to 20 kHz)	CD → sp out : 0.004% (at rated output)
Powerbandwidth	5 Hz to 100 kHz (IHF-3dB, THD 0.2%, 8 Ω)
Damping factor (1 kHz, 8 Ω)	100
Frequency characteristic	Phono → rec out (RIAA deviation) : 20 Hz to 20 kHz ± 0.2 dB CD → sp out : 2 Hz to 100 kHz + 0 -3dB
Input Sensitivity / Impedance	Phono MM : 2.5mV/47k Ω Phono MC : 160 μ V/220 Ω CD, etc. : 150mV/47k Ω
Phono maximum allowable input (1kHz/10kHz, 0.005%)	MM:210mV/1000mV MC:15mV/75mV
Rated output voltage / impedance	Tape rec, others : 150mV/560 Ω Pre out : 1V/600 Ω
Video input / output	VCR, Others : 1Vp-p/75 Ω
SN ratio (IHF-A filter input short)	Phono MM : 95 dB (5 mV input) Phono MC : 77 dB (0.5 mV input) CD, other : 107 dB
Tone Control Maximum Change (Volume -16dB)	Bass : + / - 10 dB Treble : + / - 8 dB contrabass:+10dB
Muting (under Volume Center)	-20dB
<DAC Part>
Digital input / output	Electrical : 1Vp-p/75 Ω Optical : TOSLINK criteria
Sampling frequency	32 khz, 44.1 khz, 48 khz
Total Harmonic Distortion Rate (1 kHz at 0 dB)	0.002%
Dynamic range	100dB
<General>
Power supply voltage	100 VAC, 50Hz/60Hz
Power consumption (Electrical Appliance and Material Control Law)	270W
AC outlet	Switched : 2 systems, total 200W Unswitched : 2 lines, 200W total
External dimensions	Width 477x Height 183x Depth 453 mm
Weight	32.0kg