Lo-D HCA-9000
¥ 200,000 (1 unit, around 1979)
Commentary
A is a preamplifier designed to give the highest priority to sound quality by keeping the number of circuits to the minimum necessary and carefully selecting the components constituting each of the circuit blocks through repeated trial listening.
The power supply section uses a toroidal transformer with high efficiency and low leakage flux.
In addition, the constant voltage current is NF type, and the Route 6 independent power supply system is adopted in which the source impedance is lowered and one set of constant voltage power supply is used for all amplifiers. On the output side, a large-capacity capacitor and a metallized polyester film capacitor with excellent sound quality are connected in parallel to improve sound quality.
We are working to improve the quality of all parts, with particular attention paid to the use and selection of types of capacitors.
The phase compensation capacitor uses a Styrofoam capacitor with a 500 V resistance. Two capacitors are arranged in a series for circuits that have a particularly high impact on sound quality.
Equalizer circuit The RIAA device uses metalized polyester film capacitors, the flat amplifier uses two back-to-back electrolytic capacitors, and the power supply uses metalized polycarbonate film capacitors.
The HCA 9000 circuit consists of an MC head amplifier, an equalizer amplifier and a flat amplifier.
These circuits have an ICDC configuration that does not have a coupling capacitor or a large-capacity capacitor for the feedback circuit at the input.
The MC head amplifier has a 3-stage configuration consisting of four high-gm low-noise FETs connected in parallel at the first stage, a current mirror circuit at the next stage, and a pure SEPP complimentary service stage at the last stage.
In addition, the input impedance can be switched to two levels to match MC cartridges with very low impedance.
The equalizer circuit has excellent characteristics due to linearity with a maximum output of 20 v or more when a voltage of ± 42 v is applied, metal film resistance with an error of ± 1%, and the use of capacitors with carefully selected sound quality.
The flat amplifier section uses a coupling capacitor whose characteristics have been sufficiently examined.
Equipped with a front operated phono selector, it is possible to switch between MC and MM on the front panel.
Output is designed for low output impedance.
The tape monitor switch has an off position.
Model Rating
Type | Preamplifier | ||||||
Circuit system | MC Head Amp : ICDC Configuration Equalizer Amplifier : ICLC NF Type Flat Amplifier : ICDC Configuration |
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Input Sensitivity / Impedance | Phono1, 2 mm : 2.5mV/100 Ω, 22k Ω, 47k Ω, 100k Ω 100 pF, 200 pF, 300 pF, 400 pF Phono1, 2 mc : 0.25mV/30 Ω, 100 Ω Tuner, Aux, Tape1, 2 : 150mV/47k Ω |
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Output Level / Impedance | Rec out : 150mV/600 Ω (maximum 20 V or more) Output : 1 V (maximum 20 V or more) / 30 Ω (0 ~ -40dB) |
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Phono maximum allowable input (1 kHz, RMS, THD0.01%) |
Phono1, 2 mm : 350 mV Phono1, 2 mc : 35 mV |
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Harmonic distortion factor (20 Hz to 20 kHz) |
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Frequency characteristic | Phono1 and 2 : RIAA ± 0.2 dB (20 Hz to 20 kHz) Tuner, Aux, Tape1, 2 : 5 Hz to 100 kHz + 0 -1dB |
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Signal-to-noise ratio (IHF, A-network) | Phono1, 2 mm : 90 dB (AT Input Level 2.5 mV) Phono1, 2 mc : 76 dB (AT Input Level 0.25 mV) Tuner, Aux, Tape1, 2 : 100 dB (AT Input Level 150 mV) |
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Filter Cutoff Characteristics (Phono input only) | 15 Hz, 6dB/oct. | ||||||
Intermodulation distortion factor (60 hz : 7 khz = 4 : 1) | 0.002% or Less (AT Output Level 7 v) | ||||||
Residual noise | 5 μ V or less | ||||||
Semiconductor used | Transistor : 81 FET : 24 Diode : 61 Units |
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Power supply voltage | 100 VAC, 50Hz/60Hz | ||||||
Power consumption | 45W | ||||||
AC outlet | Power switch interlock : 2 systems, max150W Power switch not interlocked : 2 systems, max400W |
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External dimensions | Width 435x Height 80x Depth 377 mm | ||||||
Weight | 8.4kg |