ONKYO Integra A-917R
¥ 90,000 (around 1993)
Unit 3 of the A-917 series, which is the 90's version of the A-817 series.
New technologies such as the newly developed constant current bias amplifier and the flat damping technology developed in the QUEST series are introduced to further improve sound quality.
In order to achieve high precision amplification, a constant current bias amplifier is used.
In order to improve the accuracy of the differential amplifier, this circuit uses an ultra-high-precision constant-current circuit as the bias circuit used as the operation reference, and has succeeded in increasing the power supply voltage fluctuation suppression ratio (SVRR).
This constant current circuit consists of a circuit configuration in which the operation reference of a high-precision feedback constant current circuit is stabilized by another constant current circuit. Moreover, this constant current circuit is also used for the bias circuit of the first stage cascode and the second stage cascode, and for the second stage constant current load, thereby realizing highly stable voltage amplification.
In addition, the power supply for the voltage amplifier is equipped with a low-impedance filter circuit independently on the left and right sides, which greatly reduces power supply voltage fluctuations caused by power supply ripple and load current at large output, and interference caused by power supply fluctuations on the left and right sides.
The flat damping technology developed in the QUEST series has been introduced, and the output coil has been successfully eliminated by making the circuit configuration more stable by adopting a new phase correction method and low-Cob transistor.
This eliminates the degradation of the damping factor in the high-frequency range and realizes a drive that does not depend on the type and characteristics of the speaker.
High linearity driver transistor with excellent characteristics up to large current region is adopted for driver transistor to improve drive performance.
The power supply section is equipped with a newly developed blue capacitor, and the bridge and diode are also large-capacity types, reducing power supply loss from the transformer to the Chemicon.
In addition, the power transformer is equipped with a special EI core that reduces the magnetic resistance around the core and makes it difficult for magnetic flux to leak, and a LASER transformer with ultra-low leakage flux that has a strict magnetic shield around the core and coil.
Newly developed anti-vibration and detent volume is used for volume.
The strength of this volume is increased by the aluminum die-cast frame, which prevents vibration of the resistor and slider and reduces noise generation.
It uses a 3 box structure chassis in which the power supply, main amplifier and volume & tone control are independent.
In addition to the gold color model, there was a black type model.
In addition, there was a side wood panel as an option sold separately.
|Type||Stereo pre-main amplifier|
|Rated output (20 Hz to 20 kHz
CD → SP-OUT, both channels driven)
|130W + 130W (6 Ω)
110W + 110W (8 Ω)
|Dynamic Power (1 kHz)||2 Ω : 300W + 300W
4 Ω : 215W + 215W
6 Ω : 165W + 165W
|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 (20 Hz ~ 20 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
|Input Sensitivity / Impedance||Phono MM : 2.5mV/47k Ω
Phono MC : 160 μ V/220 Ω
CD, Tuner, Tape, etc. : 150mV/25k Ω
|Rated output voltage / impedance||Tape Rec : 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 : + 16 dB ~ -6dB (20 Hz)
Treble : ± 10 dB (20 kHz)
|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 172x Depth 430 mm|
|Sold Separately||Side Wood Panel CW-A917 (¥ 12,000)|