VICTOR/JVC A-X1000

Commentary

Pre-main amplifier composed of dynamic super A and Gm circuit in all stages.

A Gm circuit is used for all signal circuits from the Phono equalizer to the power amplifier.
The Gm circuit is a voltage-to-current conversion amplification system. By making the transistor, which is originally a current amplification element, function straight, the SN ratio, distortion factor, transient response, and speaker drive performance during actual use are improved.
For example, the Gm equalizer is a phono equalizer that combines the advantages of the conventional NF and CR types. It realizes transient characteristics that cannot be obtained with the NF type, and broadband high S/N, low distortion rate, and wide dynamic range that cannot be obtained with the CR type.
In addition, the Gm volume prevents the increase of residual noise, distortion and crosstalk due to the volume element, and the Gm selector reduces the unnecessary gain of the amplifier to improve the actual performance expressed in the catalog specification.
This Gm circuit improves the noise level at the actual volume position by 10 to 25 dB.

In the power amplifier section, the dynamic super A power stage, which reduces switching distortion to 0, is driven by a Gm driver with low impedance to realize a power amplifier resistant to load fluctuations.
Generally speaking, as the impedance of the speaker decreases, the input impedance of the power stage also decreases. However, the output impedance of the Gm driver is low enough to maintain the required drive capacity without being affected.

The power supply is equipped with a large transformer of 420 VA and a large capacitor of 22,000 μ F.

The power transistor is covered with a shielded copper plate to reduce the influence of noise.

Equipped with side wood panels finished with a total of 21 processes of painting.

Model Rating

Type	Pre-main amplifier
Circuit System
Equalizer amplifier section	ICL, First Stage EL-FET MC/MM Dual Slope DC Servo High Gain Gm Equalizer Amplifier
Power amplifier section	Gm (GM volume / Gm selector / Gm driver) circuit + Dynamic Super A High Gain Power Amplifier
Power supply part	Direct power supply (power stage)
Overall Characteristics
Effective output (DAD, Tuner, Aux, Tape → Spout)	200W + 200W (20 Hz ~ 20 kHz, 6 Ω, THD0.005%) 170W + 170W (20 Hz ~ 20 kHz, 8 Ω, THD0.003%) 180W + 180W (1 khz, 8 ω, 0.0005% THD, By JVC Audio Analyze System)
Total harmonic distortion factor (at effective output)	DAD, Tuner, Aux, Tape → Spout : Phono MM → Spout : 0.003% (20 Hz to 20 kHz, 8 Ω) 0.0005% (1 kHz, 8 Ω, By JVC Audio Analyze System) 0.007% (20 Hz to 20 kHz, 8 Ω, Vol-30dB)
Cross modulation distortion factor	0.001% (60 Hz : 7 kHz = 4 : 1, effective output, 8 Ω, DAD, Tuner, Aux, Tape → Spout)
Switching distortion	0
TIM Distortion	0(LPF fc=100kHz)
Output bandwidth	5 Hz ~ 60 kHz (IHF, both channel operation, 8 Ω, THD0.05%, DAD, Tuner, Aux, Tape → Spout)
Frequency characteristic	3 Hz to 100 kHz + 0 -3dB (DAD, Tuner, Aux, Tape → Spout)
Damping factor	100 (1 kHz, 8 Ω, DAD, Tuner, Aux, Tape → Spout)
Input Sensitivity / Impedance (1kHz)	Phono MM : 2.5mV/47k Ω Phono MC : 200 μ V/100 Ω DAD, Tuner, Aux, Tape : 200mV/39k Ω
Signal-to-noise ratio	Phono MM : 86 dB (IHF-A short circuit) 83 dB (new IHF) Phono MC : 72 dB (IHF-A short circuit, 250 μ V input) 75 dB (new IHF) DAD, Tuner, Aux, Tape : 110 dB (IHF-A short circuit) 92 dB (new IHF)
Tone control	Bass : ± 8 dB (100 Hz) Treble : ± 8 dB (10 kHz)
Subsonic filter	18 Hz, -6dB/oct.
Loudness	+4dB(100Hz)
Muting	-20dB
Equalizer amplifier section (Phono → Rec out)
Phono maximum allowable input	Phono MM : 150 mV (1 kHz, THD0.001%) Phono MC : 11 mv (1 khz, 0.002% THD)
RIAA deviation	15 Hz ~ 30 kHz ± 0.2 dB (both MM and MC)
Total harmonic distortion factor	Phono MM : 0.002% (20 Hz to 20 kHz at 5 V output) Phono MC : 0.005% (20 Hz to 20 kHz at 7 V output)
Output Voltage / Impedance	Rec out : 200mV/660 Ω
<Others>
Power outlet	Switched : two systems Unswitched-One system
Pwer	100 VAC, 50Hz/60Hz
Rated power consumption	310W (Electrical Appliance and Material Control Law)
External dimensions	Width 477x Height 182x Depth 411 mm
Weight	18.0kg