ONKYO Integra A-917F

Commentary

A pre-main amplifier based on A-917 and improved.

The power amplifier section uses a super-current amplifier configuration unique to Onkyo.
This amplifier uses a Bi-MOS drive system that performs voltage-current conversion before the output stage. The current drive amplifier achieves stable and linear amplification by current-current amplification.
The current drive amplifier is not affected by the voltage-to-current conversion characteristics of the transistor unlike the conventional output stage. It is composed of a current amplifier that supplies the output current to the speaker in proportion to the current sent from the previous stage. It has excellent linearity and does not vary with temperature.
The Bi-MOS drive system adopted in the previous stage is a circuit using two elements, a MOS FET and a bipolar transistor. In the low-current region, the MOS FET exhibits a gentle rise curve, and in the high-current region, the stretchy and linear characteristics of the bipolar transistor are dominant. As a result, characteristics close to a straight line are obtained in the crossover region, and linearity characteristics with elongation are realized even in the large-amplitude region.
In addition, this power amplifier section has push-pull specifications for all stages with perfect symmetry of + side / - side. The current drive amplifier stage of the final stage following the differential amplifier stage of the first stage, pre-driver and Bi-MOS drive stage is 3-parallel configuration.

The power transformer is equipped with a LASER transformer originally developed by Onkyo.
The new EI core and the perfect shielding material reduce the magnetic leakage flux radiated to the surroundings by approximately 1 / 30.

The power supply section has been strengthened, and a bridge diode with a maximum current capacity 2.5 times that of the conventional one has been adopted as the rectifier diode to enable stable power supply.
In addition, the secondary winding of the power transformer is separated and independent for the power amplifier and protector circuit, and sub-transformers are mounted for the microcomputer and display. By supplying power to each stage independently, interference between each stage is eliminated.

It has a 2-box structure with the power supply and other stages separated, and a 2-division bottom chassis structure. In addition, the power stage and the small signal section are divided into blocks by a heat sink to prevent interference with the small signal section.
This reduces the influence on small signals caused by large currents handled by the power supply and power stage.

It comes with a remote control that can operate the power supply, volume, input selector and muting from your hand.
Since the volume and input rector uses a mechanical system driven by a motor, there is no non-linear distortion like semiconductor switches.

In addition to the titanium gold model, there was also a black model.

Model Rating

Type	Super current amplifier with LASER transformer
Rated output (20 Hz to 20 kHz CD → SP-OUT, both channels driven)	100W + 100W (6 Ω) 80W + 80W (8 Ω)
Dynamic Power	2 Ω : 265W + 265W 4 Ω : 205W + 205W 6 Ω : 150W + 150W
Total harmonic distortion rate (20 Hz to 20 kHz)	0.0015% (CD → SP Out, at 10W output, 8 Ω) 0.003% (Phono MM → Rec Out at 3 v output) 0.015% (Phono MC → Rec Out at 3 v output)
Intermodulation distortion factor (20 Hz to 20 kHz)	0.004% (CD → SP Out, at rated output)
Powerbandwidth	5 Hz to 100 kHz (IHF-3dB, THD 0.2%, 8 Ω)
Damping factor	150 (1 kHz, 8 Ω)
Frequency characteristic	Phono → Rec Out (RIAA deviation) : 20 Hz to 20 kHz ± 0.2 dB CD → SP Out : 2 Hz ~ 100 kHz + 0 -0.3 dB
Phono maximum allowable input (1kHz/10kHz, 0.005%)	MM:150mV/710mV MC:9mV/42mV
Input Sensitivity / Impedance	Phono MM : 2.5mV/47k Ω Phono MC : 160 μ V/220 Ω CD, Tape Play, Processor IN, etc. : 150mV/30k Ω
Rated output voltage / impedance	Tape Rec, Processor Out, etc. : 150mV/560 Ω
SN ratio (IHF-A filter input short)	Phono MM : 94 dB (5 mV input) Phono MC : 75 dB (0.5 mV input) CD, other : 107 dB
Tone Control Maximum Change	Bass : ± 10 dB (20 Hz) Treble : ± 8 dB (20 kHz)
Muting	-20dB
Pwer	100 VAC, 50Hz/60Hz
AC outlet	Switched : 2 systems, 100W Unswitched : 1 line, 100W total
Power consumption (Electrical Appliance and Material Control Law standard)	190W
External dimensions	Width 455x Height 170x Depth 430 mm
Weight	17.0kg
Attachment	Remote control